Anatomy of learning and memory

Learningis acquiring new or modifying existing knowledge, behaviors, skills, valus, or preferences and may involve synthesizing different types of information. The ability to learn is possessed by humans, animals and some machines. Progress over time tends to follow learning curves.

Human learning may occur as part of education, personal development, school or training. It may be goal-oriented and may be aided by motivation. The study of how learning occurs is part of neuropsychology, educational psychology, learning theory, and pedagogy. Learning may occur as a result of habituation or classical conditioning, seen in many animal species, or as a result of more complex activities such as play, seen only in relatively intelligent animals

Learning domainsLearning may occur consciously or without conscious awareness. There is evidence for human behavioral learning prenatally, in which habituation has been observed as early as 32 weeks into gestation, indicating that the central nervous system is sufficiently developed and primed for learning and memory to occur very early on in development

Benjamin Bloom has suggested three domains of learning:Cognitive To recall, calculate, discuss, analyze, problem solve, etc.Psychomotor To dance, swim, ski, dive, drive a car, ride a bike, etc.Affective To like something or someone, love, appreciate, fear, hate, worship, etc.

Memory: encode, store, recallhas the ability to encode, store and recall information. Memories give an organism the capability to learn and adapt from previous experiences as well as build relationships. Encoding allows the perceived item of use or interest to be converted into a construct that can be stored within the brain and recalled later from short term or long term memory. Working memory stores information for immediate use or manipulation

Types:Visual, acoustic, and semantic encodings are the most intensively used. Other encodings are also used.

encodingVisual encodingVisual encoding is the process of encoding images and visual sensory information. Visual sensory information is temporarily stored within our iconic memory and working memory before being encoded into permanent long-term storage.Baddeleys model of working memory states that visual information is stored in the visuo-spatial sketchpad.The amygdala is a complex structure that has an important role in visual encoding. It accepts visual input in addition to input from other systems and encodes the positive or negative values of conditioned stimuli.

Acoustic encodingAcoustic encoding is the processing and encoding of sound, words, and all other auditory input for storage and later retrieval.

According to Baddeley, processing of auditory information is aided by the concept of the phonological loop, which allows input within our echoic memory to be sub vocally rehearsed in order to facilitate remembering.

Studies indicate that lexical, semantic and phonological factors interact in verbal working memory. The phonological similarity effect (PSE), is modified by word concreteness. This emphasizes that verbal working memory performance cannot exclusively be attributed to phonological or acoustic representation but also includes an interaction of linguistic representation.What remains to be seen is whether linguistic representation is expressed at the time of recall or whether they participate in a more fundamental role in encoding and preservation.

encodingOther sensesTactile encoding is the processing and encoding of how something feels, normally through touch. Neurons in the primary somatosensory cortex (S1) react to vibrotactile stimuli by activating in synchronisation with each series of vibrations.[6] Odors and tastes may also lead to encode.In general encoding for short-term storage (STS) in the brain relies primarily on acoustic rather than semantic encoding

Semantic encodingSemantic encoding is the processing and encoding of sensory input that has particular meaning or can be applied to a context. Various strategies can be applied such as chunking and mnemonics to aid in encoding, and in some cases, allow deep processing, and optimizing retrieval.

Brodmanns areas 45, 46, and 47 (the left inferior prefrontal cortex or LIPC) showed significantly more activation during semantic encoding conditions compared to nonsemantic encoding conditions regardless of the difficulty of the nonsemantic encoding task presented. The same area showing increased activation during initial semantic encoding will also display decreasing activation with repetitive semantic encoding of the same words

Long term potentiationEncoding is a biological event that begins with perception All perceived and striking sensations travel to your brains hippocampus where all these sensations are combined into one single experience.The hippocampus is responsible for analyzing these inputs and ultimately deciding if they will be committed to your long term memory; these various threads of information are stored in various parts of the brain. However, the exact way in which these pieces are identified and recalled later remains unknown.

Encodingis achieved using a combination of chemicals and electricity. Neurotransmitters are released when an electrical pulse crosses the synapse which serves as a connection from nerve cells to other cells. The dendrites receive these impulses with their feathery extensions. A phenomenon called Long Term Potentiation allows a synapse to increase strength with increasing numbers of transmitted signals between the two neurons. These cells also organise themselves into groups specializing in different kinds of information processing. Thus, with new experiences your brain creates more connections and may rewire.

The brain organizes and reorganizes itself in response to your experiences, creating new memories prompted by experience, education, or training.Therefore the use of a brain reflects how it is organised.This ability to re-organize is especially important if ever a part of your brain becomes damaged. Scientists are unsure of whether the stimuli of what we do not recall are filtered out at the sensory phase or if they are filtered out after the brain examines their significance.

Mapping activity

Positron emission tomography (PET) demonstrates a consistent functional anatomical blueprint of hippocampal activation during episodic encoding and retrival. Activation in the hippocampal region associated with episodic memory encoding has been shown to occur in the rostral portion of the region whereas activation associated with episodic memory retrieval occurs in the caudal portions.

This is referred to as the Hippocampal Encoding/Retrieval model or HIPER model.

One study used PET to measure cerebral blood flow during encoding and recognition of faces in both young and older participants. Young people displayed increased cerebral blood flow in the right hippocampus and the left prefrontal and temporal cortices during encoding and in the right prefrontal and parietal cortex during recognition.

Elderly people showed no significant activation in areas activated in young people during encoding, however they did show right prefrontal activation during recognition.Thus it may be concluded that as we grow old, failing memories may be the consequence of a failure to adequately encode stimuli as demonstrated in the lack of cortical and hippocampal activation during the encoding process.

Recent findings in studies focusing on patients with posttraumatic stress disorder demonstrate that amino acid transmitters, glutamate and GABA, are intimately implicated in the process of factual memory registration, and suggest that amine neurotransmitters, norepinephrine and serotonin, are involved in encoding emotional memory.

Molecular perspective

The process of encoding is not yet well understood, however key advances have shed light on the nature of these mechanisms. Encoding begins with any novel situation, as the brain will interact and draw conclusions from the results of this interaction. These learning experiences have been known to trigger a cascade of molecular events leading to the formation of memories.

these changes include the modification of neural synapses, modification of proteins, creation of new synapses, activation of gene expression and new protein synthesis. However, encoding can occur on different levels. The first step is short-term memory formation, followed by the conversion to a long-term memory, and then a long-term memory consolidation process.

Synaptic plasticity

Synaptic plasticity is the ability of the brain to strengthen, weaken, destroy and create neural synapses and is the basis for learning.

These molecular distinctions will identify and indicate the strength of each neural connection.

The effect of a learning experience depends on the content of such an experience. Reactions that are favoured will be reinforced and those that are deemed unfavourable will be weakened.

This shows that the synaptic modifications that occur can operate either way, in order to be able to make changes over time depending on the current situation of the organism. In the short term, synaptic changes may include the strengthening or weakening of a connection by modifying the preexisting proteins leading to a modification in synapse connection strength. In the long term, entirely new connections may form or the number of synapses at a connection may be increased, or reduced.

The encoding process

A significant short-term biochemical change is the covalent modification of pre-existing proteins in order to modify synaptic connections that are already active. This allows data to be conveyed in the short term, without consolidating anything for permanent storage. From here a memory or an association may be chosen to become a long-term memory, or forgotten as the synaptic connections eventually weaken. The switch from short to long-term is the same concerning both implicit memory and explicit memoryThis process is regulated by a number of inhibitory constraints, primarily the balance between protein phosphorylation and dephosphorylation

Finally, long term changes occur that allow consolidation of the target memory. These changes include new protein synthesis, the formation of new synaptic connections and finally the activation of gene expression in accordance with the new neural configuration.The encoding process has been found to be partially mediated by serotonergic interneurons, specifically in regard to sensitization as blocking these interneurons prevented sensitization entirely. However, the ultimate consequences of these discoveries have yet to be identified. Furthermore, the learning process has been known to recruit a variety of modulatory transmitters in order to create and consolidate memories. These transmitters cause the nucleus to initiate processes required for neuronal growth and long term memory, mark specific synapses for the capture of long-term processes, regulate local protein synthesis and even appear to mediate attentional processes required for the formation and recall of memories.

Storage in human memory is one of three core process of memory, along with Recall and Encoding. It refers to the retention of information, which has been achieved through the encoding process, in brain for prolonged period of time until it is accessed by the recall process. Modern memory psychology differentiates the two distinct type of memory storage; short-term memory and long-term memory. In addition, different memory models have suggested variations of existing short-term and long-term memory to account for different ways of storing memory.

Models of Memory StorageVarieties of different memory models have been proposed to account for different type of recall process, including the cued recall, free recall, and serial recall. In order to explain the recall process, however, the memory model must identify how an encoded memory can reside in the memory storage for prolonged period of time until the memory is accessed again, during the recall process. Not all models, however, use the terminology of Short-Term and Long-Term Memory to explain the memory storage; the Dual-Store theory and refined version of Atkinson-Shiffrin Model of Memory (Atkinson 1968) uses both Short-Term and Long-Term memory storage, but others do not.

Recallin memory refers to the retrieval of events or information from the past. Along with encoding and storage, it is one of the three core processes of memory.

There are three main types of recall: free recall, cued recall and serial recall. Psychologists test these forms of recall as a way to study the memory processes of humans and animals. Two main theories of the process of recall are the Two-Stage Theory and the theory of Encoding Specificity.

recallTwo-stage theoryThe two-stage theory states that the process of recall begins with a search and retrieval process, and then a decision or recognition process where the correct information is chosen from what has been retrieved. In this theory, recognition only involves the latter of these two stages, or processes, and this is thought to account for the superiority of the recognition process over recall. Recognition only involves one process in which error or failure may occur, while recall involves two.However, recall has been found to be superior to recognition in some cases, such as a failure to recognize words that can later be recalled.

Encoding specificityThe theory of encoding specificity finds similarities between the process of recognition and that of recall. The encoding specificity principle states that memory utilizes information from the memory trace, or the situation in which it was learned, and from the environment in which it is retrieved. Encoding specificity helps to take into account context cues because of its focus on the retrieval environment, and it also accounts for the fact recognition may not always be superior to recall

Brain Structures involve in memoryThe neuroanatomy of memory encompasses a wide variety of anatomical structures in the brain.

Subcortical structures

HippocampusCerebellumAmygdalaBasal gangliaCortical structures

Frontal lobeTemporal lobeParietal lobeOccipital lobe

hippocampusThe hippocampus is located in the medial temporal lobe of the brain In this lateral view of the human brain, the frontal lobe is at left, the occipital lobe at right, and the temporal and parietal lobes have largely been removed to reveal the hippocampus underneath.

Hippocampus

The hippocampusThe hippocampus is a structure in the brain that has been associated with various memory functions. It is part of the limbic system, and lies next to the medial temporal lobe. It is made up of two structures, the Ammons Horn, and the Dentate gyrus, each containing different types of cells

Cognitive mapsThere is evidence that the hippocampus contains cognitive maps in humans. In one study, single-cell recordings were taken from electrodes implanted in a rats hippocampus, and it was found that certain neurons responded strongly only when the rat was in certain locations.

These cells are called place cells, and collections of these cells can be considered to be mental maps. Individual place cells do not only respond to one unique area only however, the patterns of activation of these cells overlap to form layered mental maps within the hippocampus. A good analogy is the example of the same television or computer screen pixels being used to light up any trillions of possible combinations to produce images, just as the place cells can be used in any multiple possible combinations to represent mental map

The hippocampus right side is more oriented towards responding to spatial aspects, whereas the left side is associated with other context information. Also, there is evidence that experience in building extensive mental maps, such as driving a city taxi for a long time (since this requires a lot of memorization of routes), can increase the volume of ones hippocampus.

EncodingDamage to the hippocampus and surrounding area can cause anterograde amnesia, the inability to form new memories.This implies that the hippocampus is important not only for storing cognitive maps, but for encoding memories

The hippocampus is also involved in memory consolidation, the slow process by which memories are converted from short to long term memory This is supported by studies in which lesions are applied to rat hippocampi at different times after learning. The process of consolidation may take up to a couple years.It has also been found that it is possible to form new semantic memories without the hippocampus, but not episodic memories, which means that explicit descriptions of actual events (episodic) cannot be learned, but some meaning and knowledge is gained from experiences (semantic).

hippocampus

The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Like the cerebral cortex, with which it is closely associated, it is a paired structure, with mirror-image halves in the left and right sides of the brain. In humans and other primates, the hippocampus is located inside the medial temporal lobe, beneath the cortical surface. It contains two main interlocking parts: Ammon's horn and the dentate gyrus.

In Alzheimer's disease, the hippocampus is one of the first regions of the brain to suffer damage; memory problems and disorientation appear among the first symptoms. Damage to the hippocampus can also result from oxygen starvation (hypoxia), encephalitis, or medial temporal lobe epilepsy. People with extensive, bilateral hippocampal damage may experience anterograde amnesiathe inability to form or retain new memories

Since different neuronal cell types are neatly organized into layers in the hippocampus, it has frequently been used as a model system for studying neurophysiology. The form of neural plasticity known as long-term potentiation (LTP) was first discovered to occur in the hippocampus and has often been studied in this structure. LTP is widely believed to be one of the main neural mechanisms by which memory is stored in the brain

The earliest description of the ridge running along the floor of the temporal horn of the lateral ventricle comes from the Venetian anatomist Julius Caesar Aranzi (1587), who initially likened it to a seahorse, using the Latin: hippocampus (from Greek: , "horse" and Greek: , "sea monster") or alternatively to a silkworm.

the German anatomist Duvernoy (1729), the first to illustrate the structure, also wavered between "seahorse" and "silkworm." "Ram's horn" was proposed by the Danish anatomist Jacob Winslw in 1732; and a decade later his fellow Parisian, the surgeon de Garengeot, used "cornu Ammonis" - horn of (the ancient Egyptian god) Amun

hippocampus

The hippocampus as a whole has the shape of a curved tube, which has been analogized variously to a seahorse, a ram's horn (Cornu Ammonis, hence the subdivisions CA1 through CA4), or a banana.[3

hippocampusToday, the structure is called the hippocampus rather than hippocampus major, with pes hippocampi often being regarded as synonymous with De Garengeot's "cornu Ammonis",[2] a term which survives in the names of the four main histological divisions of the hippocampus: CA1, CA2, CA3 and CA4

Over the years, three main ideas of hippocampal function have dominated the literature: inhibition, memory, and space.

Role hippocampusThe major line of thought relates the hippocampus to memory. Although it had historical precursors, this idea derived its main impetus from a famous report by Scoville and Brenda Milner[12] describing the results of surgical destruction of the hippocampus (in an attempt to relieve epileptic seizures), in a patient named Henry Gustav Molaison,[13] known until his death in 2008 as H.M. The unexpected outcome of the surgery was severe anterograde and partial retrograde amnesia

The important theory of hippocampal function relates the hippocampus to space. The spatial theory was originally championed by O'Keefe and Nadel, who were influenced by E.C. Tolman's theories about "cognitive maps" in humans and animals

that animals with hippocampal damage tend to be hyperactive; second, that animals with hippocampal damage often have difficulty learning to inhibit responses that they have previously been taught, especially if the response requires remaining quiet as in a passive avoidance test. Jeffrey Gray developed this line of thought into a full-fledged theory of the role of the hippocampus in anxiety.[10] The inhibition theory is currently the least popular of the three.[11]

Role in memory

Psychologists and neuroscientists generally agree that the hippocampus has an important role in the formation of new memories about experienced events (episodic or autobiographical memory).Part of this role is hippocampal involvement in the detection of novel events, places and stimuli.

Some researchers view the hippocampus as part of a larger medial temporal lobe memory system responsible for general declarative memory (memories that can be explicitly verbalizedthese would include, for example, memory for facts in addition to episodic memory).

hippocampusLocation:medial to the temporal horn of the lateral ventriclein the deep anterior temporal lobeArchitecture:seahorse shape structure composeof the dentate gyrus, CA regions, and subiculum. It has 3 layer neuronal layers

Circuitry:Internal circuitry:entorhinal cortex-dentate gyrus-CA3-CA1-subiculum-entorhinal cortexMajor external circuit: Papez circuit: hippocampus-fornix-mammilary body-anterior nucleus of thalamus-cingulate cortex-temporal cortex-hippocampus

Inputs - outputsInputsSeptal nuclei-fornix (cholinergic input vital for memory and degerates in alzheimer`s diseaseMultiple cortical areas-entorhinal cortex-dentate gyrusInputs to entorhinal: sensory assosiation cortices,prefronatal,amygdala,olfactoryInputs to subiculum: amygdala,cingulate cortexInputs to hippocampus:raphe nuclei (5HT),locus coeruleus (NE)

OutputsSubiculum-fornix-mammillary bodyCA1/CA3-fornix-septal nuclei,nucleus accumbens,hypothalamus,cingulate cortex,frontal lobe

basal ganglia (or basal nuclei) are a group of nuclei of varied origin (mostly telencephalic embryonal origin, with some diencephalic and mesencephalic elements) in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus and other brain areas.

The basal ganglia are associated with a variety of functions, including voluntary motor control, procedural learning relating to routine behaviors or "habits" such as bruxism, eye movements, and cognitive,emotional functions.Currently popular theories implicate the basal ganglia primarily in action selection, that is, the decision of which of several possible behaviors to execute at a given time.

location

Main componentsThe main components of the basal ganglia are the striatum (also called neostriatum) composed of caudate and putamen, globus pallidus or pallidum composed of globus pallidus externa (GPe) and globus pallidus interna (GPi), substantia nigra composed of both substantia nigra pars compacta (SNc) and substantia nigra pars reticulata (SNr), and the subthalamic nucleus (STN).

The largest component, the striatum, receives input from many brain areas but sends output only to other components of the basal ganglia. The pallidum receives its most important input from the striatum (either directly or indirectly), and sends inhibitory output to a number of motor-related areas, including the part of the thalamus that projects to the motor-related areas of the cortex. One part of substantia nigra, the reticulata (SNr), functions similarly to the pallidum, and another part (compacta or SNc) provides the source of the neurotransmitter dopamine's input to the striatum. The subthalamic nucleus (STN) receives input mainly from the striatum and cortex, and projects to a portion of the pallidum (interna portion or GPi). Each of these areas has a complex internal anatomical and neurochemical organization.

Role basal gangliaThe basal ganglia play a central role in a number of neurological conditions, including several movement disorders. The most notable are Parkinson's disease, which involves degeneration of the melanin-pigmented dopamine-producing cells in the substantia nigra pars compacta (SNc), and Huntington's disease, which primarily involves damage to the striatum.

Basal ganglia dysfunction is also implicated in some other disorders of behavior control such as the Tourette's syndrome, ballismus (particularly hemibalismus), obsessivecompulsive disorder (OCD), and Wilson's disease (Hepatolenticular degeneration); except for Wilson's disease and hemiballismus, the neuropathological mechanisms underlying diseases of ganglia such as Parkinsons' and Huntington's are not very well understood or are at best still developing theories.[citation needed]

location

4 partsIn terms of anatomy, the basal ganglia are divided by anatomists into four distinct structures, depending on how superior or rostral they are (in other words depending on how close to the top of the head they are): Two of them, the striatum and the pallidum, are relatively large; the other two, the substantia nigra and the subthalamic nucleus, are smaller. In the illustration to the right, two coronal sections of the human brain show the location of the basal ganglia components. Of note, and not seen in this section, the subthalamic nucleus and substantia nigra lie farther back (posteriorly) in the brain than the striatum and pallidum.

the structures relevant to the basal ganglia are shown in boldTelencephalon: The human cortex (both hemispheres), Caudate, Putamen, Globus pallidus (pallidum) Diencephalon: Thalamus, hypothalamus, subthalamus, epithalamus, subthalamic nuclei

Mesencephalon (Midbrain), Substantia nigra pars compacta (SNc), Substantia nigra pars reticulata (SNr)

circuitCircuit connectionsexcitatory glutamatergic pathways, inhibitory GABAergic pathways, and modulatory dopaminergic pathways (Abbreviations: GPe: globus pallidus external; GPi: globus pallidus internal; STN: subthalamic nucleus; SNc: substantia nigra compacta; SNr: substantia nigra reticulata)In order to understand the complex circuitry of the basal ganglia, one has to first understand the important participants in this circuit. Parts of the basal ganglia are in direct communication with the thalamus and the cortex. The cortex, thalamus, and the basal ganglia are, therefore, the three main participants in the circuit created by the basal ganglia.

At the top of the hierarchy lies the cerebral cortex. The cortex has many different areas with different functions. One such cortical area is called the primary motor cortex (along the pre-central gyrus). Specialized neurons from the primary motor cortex extend their axons all the way to the striatum portion of the basal ganglia. These cortical neurons release the neurotransmitter glutamate, which is excitatory in nature. Once excited by glutamate, the cells in the striatum project in two different directions giving rise to two major pathways: The "direct" and the "indirect" pathways:

The following diagram depicts the direct pathway:Cortex (stimulates) Striatum (inhibits) "SNr-GPi" complex (less inhibition of thalamus) Thalamus (stimulates) Cortex (stimulates) Muscles, etc. (hyperkinetic state)

Cortex (stimulates) Striatum (inhibits) GPe (less inhibition of STN) STN (stimulates) "SNr-GPi" complex (inhibits) Thalamus (is stimulating less) Cortex (is stimulating less) Muscles, etc. (hypokinetic state)

Parkinson vs huntington diseaseInformation about the functions of the basal ganglia comes from anatomical studies, from physiological studies carried out mainly in rats and monkeys, and from the study of diseases that damage them.The greatest source of insight into the functions of the basal ganglia has come from the study of two neurological disorders, Parkinson's disease and Huntington's disease.

For both of these disorders, the nature of the neural damage is well understood and can be correlated with the resulting symptoms. Parkinson's disease involves major loss of dopaminergic cells in the substantia nigra; Huntington's disease involves massive loss of medium spiny neurons in the striatum.

The symptoms of the two diseases are virtually opposite: Parkinson's disease is characterized by gradual loss of the ability to initiate movement, whereas Huntington's disease is characterized by an inability to prevent parts of the body from moving unintentionally.

It is noteworthy that, although both diseases have cognitive symptoms, especially in their advanced stages, the most salient symptoms relate to the ability to initiate and control movement. Thus, both are classified primarily as movement disorders. A different movement disorder, called hemiballismus, may result from damage restricted to the subthalamic nucleus. Hemiballismus is characterized by violent and uncontrollable flinging movements of the arms and legs.

The role in motivation of the "limbic" part of the basal gangliathe nucleus accumbens (NA), ventral pallidum, and ventral tegmental area (VTA)is particularly well established. Thousands of experimental studies combine to demonstrate that the dopaminergic projection from the VTA to the NA plays a central role in the brain's reward system. Animals with stimulating electrodes implanted along this pathway will bar-press very energetically if each press is followed by a brief pulse of electrical current. Numerous things that people find rewarding, including addictive drugs, good-tasting food, and sex, have been shown to elicit activation of the VTA dopamine system. Damage to the NA or VTA can produce a state of profound torpor.

Basal gangliaInvolved in initiation and modulation of movement, receive input from cerebral cortex, process it, and relay back to cerebral cortex via thalamusConsists: corpus striatum (striatum + pallidum)(striatum:nucleus caudatus+ putamen) ,globus pallidus (pallidum, + putamen: nucleus lentiformis); amygdala, claustrum

Nucleus caudatusC shaped, is lateral to the lateral ventricle, composes: head, body and tailHead, bulges into the frontal horn of lateral ventricle, connect to the lentiform nucleus; body sweeps into a c shaped with the lateral ventricle, capsula interna ;tail located in the temporal lobe superior and lateral to the temporal horn of the lateral ventricle, connect to amigdaloid bodyDegeneration lead : Huntington`s disesae

Putamen & globus pallidusLens shaped, lateral to globus pallidus, anteriorly and inferiorly is connected to nucleus caudatusCorpus striatum: putamen + nucleus caudatusGlobus pallidus- pale globeNucleus lentiformis= putamen + globus pallidus

Substantia nigraLocated in the ventral midbrain, appears brown, neuromelanin pigmentationPars compacta- has dopamine producing neuron, project to striatum and facilitate movementPars reticularis-is an output nucleusDegeneration causes: parkinson`s disease;Chorea=lesion is above and medial subtantia nigra; athetosis= it is above and lateral to itBallism, hemibalismus =subthalamic nucleus; tremor =lesion between subtantia nigra and red nucleus

Basal ganglia and motor memory

The basal gangliaThe basal ganglia are a group of nuclei which are located in the medial temporal lobe, above the thalamus and connected to the cerebral cortex.

Specifically, the basal ganglia includes the subthalamic nucleus, substantia nigra, the globus pallidus, the ventral striatum and the dorsal striatum, which consists of the putamen and the caudate nucleus

The basic functions of these nuclei deal with cognition, learning, and motor control and activities. The basal ganglia are also associated with learning, memory, and unconscious memory processes, such as motor skills and implicit memory

The caudate nucleus is thought to assist in learning and memory of associations taught during operant conditioning. Specifically, research has shown that this part of the basal ganglia plays a role in acquiring stimulus-response habits, as well as in solving sequence tasks

Damage to the basal ganglia has been linked to dysfunctional learning of motor and perceptual-motor skills. Most disorders that are associated with damage to these areas of the brain involve some type of motor dysfunction, as well as trouble with mental switching between tasks in working memory Such symptoms are often present in those who suffer from dystonia, , athymhormic syndrome, Fahr's syndrome, Huntington's disease or Parkinson's disease. Huntington's and Parkinson's disease involve both motor deficits and cognitive impairment

amygdalalocationSubdivision

amygdalaThe amygdalae (/mdli/; singular: amygdala; also corpus amygdaloideum; Latin, from Greek , amygdal, 'almond', 'tonsil', listed in the Gray's Anatomy as the nucleus amygdal)[1] are almond-shaped groups of nuclei located deep within the medial temporal lobes of the brain in complex vertebrates, including humans.Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.

Connections

The amygdala sends impulses to the hypothalamus for activation of the sympathetic nervous system, to the thalamic reticular nucleus for increased reflexes, to the nuclei of the trigeminal nerve and the facial nerve, and to the ventral tegmental area, locus coeruleus, and laterodorsal tegmental nucleus for activation of dopamine, norepinephrine and epinephrine.Coronal section of brain through intermediate mass of third ventricle.

The cortical nucleus is involved in the sense of smell and pheromone-processing. It receives input from the olfactory bulb and olfactory cortex. The lateral amygdalae, which send impulses to the rest of the basolateral complexes and to the centromedial nuclei, receive input from the sensory systems. The centromedial nuclei are the main outputs for the basolateral complexes, and are involved in emotional arousal in rats and cats.

amygdala

Role amygdaladuring fear conditioning, sensory stimuli reach the basolateral complexes of the amygdalae, particularly the lateral nuclei, where they form associations with memories of the stimuli. The association between stimuli and the aversive events they predict may be mediated by long-term potentiation, a sustained enhancement of signalling between affected neurons.Memories of emotional experiences imprinted in reactions of synapses in the lateral nuclei elicit fear behavior through connections with the central nucleus of the amygdalae and the bed nuclei of the stria terminalis (BNST). The central nuclei are involved in the genesis of many fear responses, including freezing (immobility), tachycardia (rapid heartbeat), increased respiration, and stress-hormone release. Damage to the amygdalae impairs both the acquisition and expression of Pavlovian fear conditioning, a form of classical conditioning of emotional responses.[3]The amygdalae are also involved in appetitive (positive) conditioning. It seems that distinct neurons respond to positive and negative stimuli, but there is no clustering of these distinct neurons into clear anatomical nuclei.However, lesions of the central nucleus in the amygdala have been shown to reduce appetitive learning in rats. Lesions of the basolateral lesions do not exhibit the same effect.Research like this indicates that different nuclei within the amygdala have different functions in appetitive conditioning

Amygdala

The amygdalaLocated below the hippocampus in the medial temporal lobes are two amygdalae (singular "amygdala").

The amygdala are associated with both emotional learning and memory, as it responds strongly to emotional stimuli, especially fear.

These neurons assist in encoding emotional memories and enhancing them. This process results in emotional events being more deeply and accurately encoded into memory. Lesions to the amygdalae in monkeys have been shown to impair motivation, as well as the processing of emotions

Memory of fear conditioning

Pavlovian conditioning tests have shown the active role of the amygdala in fear conditioning in rats. Research involving lesions to the basolateral nucleus have shown a strong association with memories involving fear. The central nucleus is linked with the behavioral responses that are dependent on the basolaterals reaction to fear.

The central nucleus of the amygdala is also linked to emotions and behaviors motivated by food and sex

Memory consolidation

Emotional experiences and events are somewhat fragile and take a while to be completely set into memory. This slow process, referred to as consolidation, allows emotions to influence the way the memory is stored.

The amygdala is involved in memory consolidation, which is the process of transferring information that is currently in working memory into ones long-term memory. This process is also known as memory modulation.

The amygdala works to encode recent emotional information into memory. Memory research has shown that the greater ones emotional arousal level at the time of the event, the greater the chance that the event will be remembered. This may be due to the amygdala enhancing the emotional aspect of the information during encoding, causing the memory to be processed at a deeper level and therefore, more likely to withstand forgetting.

amygdalaAlmond shaped, located anterior to the hippocampus in the anterior portion of medial temporal lobeInputs:major= temporal lobe, olfactory, limbic, autonomic information from orbitofrontal, cingulate gyrus, hypothalamus, tegmentum, brainstem: DA (ventral tegmental area), NE(raphe nuclei), 5HT(locus coeruleus)Outputs: major= hypothalamus, thalamus, striatum,septal nuclei, hippocampus, multiple cortical areasFunction: regulates emotional interpretation, relating to fear and anger

Limbic systemA system of nuclear structures and tracts found in a ring that encircles the thalamusMultiple structures interact with each other and with other cortical and subcortical structure, function serves major regulator of emotional control and memory encodingDamage can lead aggression, apathy, anterograde amnesia (inability to form new memories)

Major limbic forebrain structuresHippocampus: memory encodingFornix:C shaped, extend hippocampus travels inferior to corpus callosum-dives down to mamillary bodyAmygdalaStria terminalis, c shaped tract connecting amygdala to the hypothalamus and basal forebrainHabenula, small nuclear structure, rostral the pineal gland, part of epithalamusSeptal nuclei, set of nuclear structurs rostral to anterior commisura, as a pleasure centre of the brain; connection with hippocampus, amygdala, and hypothalamusCingulate cortex:above corpus callosum, involve in papez circuit, function in cortical regulation of autonomic function, behavior, emotional modulation pain

Gyrus cinguli

Frontal lobe

The frontal lobes are located at the front of each cerebral hemisphere and positioned anterior to the parietal lobes. It is separated from the parietal lobe by the primary motor cortex, which controls voluntary movements of specific body parts associated with the precentral gyrus.The cortex here serves our ability to plan the day, organize work, type a letter, pay attention to details and control the movements of your arms and legs. It also contributed to your personality and behaviour.

When considering the frontal lobes in regards to memory, we see that it is very important in the coordination of information.

Therefore, the frontal lobes are important in working memory, For example, when you are thinking about how to get to a mall you have never been to before, you combine various bits of knowledge you already have: the layout of the city the mall is in, information from a map, knowledge of traffic patterns in that area and conversations with your friends about the location of the mall. By actively using all of this information, you can determine the best route for you to take. This action involves the controlled use of information in working memory, coordinated by the frontal lobes.

The frontal lobe contains most of the dopamine-sensitive neurons in the cerebral cortex. The dopamine system is associated with reward, attention, short-term memory tasks, planning, and drive. Dopamine tends to limit and select sensory information arriving from the thalamus to the fore-brain. A report from the National Institute of Mental Health says a gene variant that reduces dopamine activity in the prefrontal cortex is related to poorer performance and inefficient functioning of that brain region during working memory tasks, and to slightly increased risk for schizophrenia.

The executive functions of the frontal lobes involve the ability to recognize future consequences resulting from current actions, to choose between good and bad actions (or better and best), override and suppress unacceptable social responses, and determine similarities and differences between things or events. Therefore, it is involved in higher mental functions.The frontal lobes also play an important part in retaining longer term memories which are not task-based. These are often memories associated with emotions derived from input from the brain's limbic system. The frontal lobe modifies those emotions to generally fit socially acceptable norms.Psychological tests that measure frontal lobe function include finger tapping, Wisconsin Card Sorting Task, and measures of verbal and figural fluency.[2]

The frontal lobes help a person select out memories that are most relevant on a given occasion. It can coordinate various types of information into a coherent memory traceFor example, the knowledge of the information itself, as well as knowing where information came from must be put together into a single memory representation; this is called source monitoring.

Sometimes we experience situations where information becomes separated, such as when we recall something, but cannot remember where we remember it from; this is referred to as a source monitoring error

The frontal lobes are also involved in the ability to remember what we need to do in the future; this is called prospective memory

Temporal lobe

The temporal lobes are a region of the cerebral cortex that is located beneath the Sylvian fissure on both the left and right hemispheres of the brain.Lobes in this cortex are more closely associated with memory and in particular autobiographical memory

The temporal lobes are also concerned with recognition memory. This is the capacity to identify an item as one that was recently encountered.Recognition memory is widely viewed as consisting of two components, a familiarity component (i.e. Do I know this person waving at me?) and a recollective component (i.e. That is my friend Julia, from evolutionary psychology class).

Damage to the temporal lobe can affect an individual in a litany of ways ranging from: disturbance of auditory sensation and perception, disturbance of selective attention of auditory and visual input, disorders of visual perception, impaired organization and categorization of verbal material, disturbance of language comprehension, and altered personality.

In regard to memory, temporal lobe damage can impair long-term memory

Thus, general semantic knowledge or more personal episodic memories of ones childhood could be affected.

The temporal lobe is involved in auditory perception and is home to the primary auditory cortex. It is also important for the processing of semantics in both speech and vision. The temporal lobe contains the hippocampus and plays a key role in the formation of long-term memory.

The superior temporal gyrus includes an area (within the Sylvian fissure) where auditory signals from the cochlea (relayed via several subcortical nuclei) first reach the cerebral cortex. This part of the cortex (primary auditory cortex) is involved in hearing. Adjacent areas in the superior, posterior and lateral parts of the temporal lobes are involved in high-level auditory processing. In humans this includes speech, for which the left temporal lobe in particular seems to be specialized. Wernicke's area, which spans the region between temporal and parietal lobes, plays a key role (in tandem with Broca's area, which is in the frontal lobe). The functions of the left temporal lobe are not limited to low-level perception but extend to comprehension, naming, verbal memory and other language functions.

The underside (ventral) part of the temporal cortices appear to be involved in high-level visual processing of complex stimuli such as faces (fusiform gyrus) and scenes (parahippocampal gyrus). Anterior parts of this ventral stream for visual processing are involved in object perception and recognition.The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemispheres) are thought to be involved in episodic/declarative memory. Deep inside the medial temporal lobes lie the hippocampi, which are essential for memory function - particularly the transference from short to long term memory and control of spatial memory and behavior. Damage to this area typically results in anterograde amnesia.

The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex.[1] The primary visual cortex is Brodmann area 17, commonly called V1 (visual one). Human V1 is located on the medial side of the occipital lobe within the calcarine sulcus; the full extent of V1 often continues onto the posterior pole of the occipital lobe. V1 is often also called striate cortex because it can be identified by a large stripe of myelin, the Stria of Gennari. Visually driven regions outside V1 are called extrastriate cortex. There are many extrastriate regions, and these are specialized for different visual tasks, such as visuospatial processing, color discrimination and motion perception. The name derives from the overlying occipital bone, which is named from the Latin oc- + caput, "back of the head".

Significant functional aspects of the occipital lobe is that it contains the primary visual cortex and is the part of the brain where dreams come from.Retinal sensors convey stimuli through the optic tracts to the lateral geniculate bodies, where optic radiations continue to the visual cortex. Each visual cortex receives raw sensory information from the outside half of the retina on the same side of the head and from the inside half of the retina on the other side of the head. The cuneus (Brodmann's area 17) receives visual information from the contralateral superior retina representing the inferior visual field. The lingula receives information from the contralateral inferior retina representing the superior visual field. The retinal inputs pass through a "way station" in the lateral geniculate nucleus of the thalamus before projecting to the cortex. Cells on the posterior aspect of the occipital lobes' gray matter are arranged as a spatial map of the retinal field. Functional neuroimaging reveals similar patterns of response in cortical tissue of the lobes when the retinal fields are exposed to a strong pattern.If one occipital lobe is damaged, the result can be homonomous vision loss from similarly positioned "field cuts" in each eye. Occipital lesions can cause visual hallucinations. Lesions in the parietal-temporal-occipital association area are associated with color agnosia, movement agnosia, and agraphia.

Parietal lobe

The parietal lobe is located directly behind the central sulcus, superior to the occipital lobe and posterior to the frontal lobe, visually at the top of the back of the head.

The make up of the parietal lobe is defined by four anatomical boundaries in the brain, providing a division of all the four lobes.

The parietal lobe has many functions and duties in the brain and its main functioning can be divided down into two main areas: (1) sensation and perception (2) constructing a spatial coordinate system to represent the world around us.

The parietal lobe helps us to mediate attention when necessary and provides spatial awareness and navigational skills. Also, it integrates all of our sensory information (touch, sight, pain etc.) to form a single perception.Parietal lobe gives the ability to focus our attention on different stimuli at the same time, PET scans show high activity in the parietal lobe when participates being studied were asked to focus their attention at two separate areas of attention.Parietal lobe also assists with verbal short term memory and damage to the supramarginal gyrus cause short term memory loss.

Damage to the parietal lobe results in the syndrome neglect which is when patients treat part of their body or objects in their visual field as though it never existed. Damage to the left side of the parietal lobe can result in what is called Gerstmann syndromeIt includes right-left confusion, difficulty with writing (agraphia, and difficulty with mathematics (acalculia. It can also produce disorders of language (aphasia, and the inability to perceive objects

Damage to the right parietal lobe can result in neglecting part of the body or space (contralateral neglect), which can impair many self-care skills such as dressing and washing. Right side damage can also cause difficulty in making things (constructional apraxia, denial of deficits (anosagnosia) and drawing ability.Neglect syndrome tends to be more prevalent on the right side of the parietal lobe, because the right mediates attention to both the left and right fields.Damage in the somatic sensory cortex results in loss of perception of bodily sensations, namely sense of touch.

The parietal lobe integrates sensory information from different modalities, particularly determining spatial sense and navigation. For example, it comprises somatosensory cortex and the dorsal stream of the visual system. This enables regions of the parietal cortex to map objects perceived visually into body coordinate positions.The name derives from the overlying parietal bone, which is named from the Latin pariet-, wall.

The parietal lobe plays important roles in integrating sensory information from various parts of the body, knowledge of numbers and their relations,[1] and in the manipulation of objects. Portions of the parietal lobe are involved with visuospatial processing. Although multisensory in nature, the posterior parietal cortex is often referred to by vision scientists as the dorsal stream of vision (as opposed to the ventral stream in the temporal lobe). This dorsal stream has been called both the 'where' stream (as in spatial vision)[2] and the 'how' stream (as in vision for action).[3]Various studies in the 1990s found that different regions of the posterior parietal cortex in Macaques represent different parts of space.The lateral intraparietal (LIP) contains a map of neurons (retinotopically-coded when the eyes are fixed[4]) representing the saliency of spatial locations, and attention to these spatial locations. It can be used by the oculomotor system for targeting eye movements, when appropriate.[5]The ventral intraparietal (VIP) area receives input from a number of senses (visual, somatosensory, auditory, and vestibular[6]). Neurons with tactile receptive fields represented space in a head-centered reference frame.[6] The cells with visual receptive fields also fire with head-centered reference frames[7] but possibly also with eye-centered coordinates[6]The medial intraparietal (MIP) area neurons encode the location of a reach target in nose-centered coordinates.[8]The anterior intraparietal (AIP) area contains neurons responsive to shape, size, and orientation of objects to be grasped[9] as well as for manipulation of hands themselves, both to viewed[9] and remembered stimuli.[10]

Occipital lobe

The occipital lobe is the smallest of all four lobes in the human cerebral cortex and located in the rearmost part of the skull and considered to be part of the forebrain

The occipital lobe sits directly above the cerebellum and is situated posterior to the Parieto-occipital sulcus, or parieto-occipital sulcus.This lobe is known as the centre of the visual perception system, the main function of the occipital lobe is that of vision.

Retinal sensors send signals through the optic tract to the Lateral geniculate nucleusOnce the Lateral Geniculate Nucleus receives the information it is sent down the primary visual cortex where it is organized and sent down one of two possible path ways; dorsal or ventral streamThe ventral stream is responsible for object representation and recognition and is also commonly known as the "what" stream. The dorsal stream is responsible for guiding our actions and recognizing where objects are in space, commonly known as the "where" or "how" stream. Once in the information is organized and send through the pathways it continues to the other areas of the brain responsible for visual processing.

The most important function of the Occipital lobe is vision. Due to the positioning of this lobe at the back of the head it is not susceptible to much injury but any significant damage to the brain can cause a variety of damage to our visual perception system. Common problems in the occipital lobe are field defects and scotomas, movement and colour discrimination, hallucinations, illusions, inability to recognize words and inability to recognize movement.A study was done in which patients suffered from a tumour on the occipital lobe and the results shows that the most frequent consequence was contralateral damage to the visual field.

When damage occurs in the occipital lobe it is most common to see the effects on the opposite side of the brain. Since the brain regions are so specialized in their functioning damages done to specific areas of the brain can cause specific type of damage. Damage to the left side of the brain can lead to language discrepancies, i.e. difficulty in properly identifying letters, numbers and words, inability to incorporate visual stimuli to comprehend multiple ways an object can be found.

Right side damage causes non-verbal problems, i.e. identifying geometric shapes, perception of figures and faces

In almost all regions of the brain left side damage leads to general language problems where as right side damage leads to general perception and problem solving skills.

Damage to the cortex

Many studies of different disease and disorders that have symptoms of memory loss have provided reinforcing evidence to the study of the anatomy of the brain and which parts are more utilized in memory.

Frontotemporal lobar degeneration (FTLD) is a common form of dementia due to the degeneration of the frontal and temporal lobes. Studies have found significant decreases in the essential needs for proper functioning in these lobes. The autobiographical domain in memory is largely affected by this disease. In one study, FTLD patients were interviewed and asked to describe a significant event from five different periods of their lives. Using the interview and different methods of imaging, the experimenters hoped to find links between patterns of brain volume loss and performance in the interview

Parkinson's disease involves both damage to the basal ganglia and certain memory dysfunctions, suggesting that the basal ganglia are involved in specific types of memory. Those who have this disease have problems with both their working memory and spatial memory.Most people can instantly and easily use visual-spatial memory to remember locations and pictures, but a person with Parkinson's disease would find this difficult. He or she would also have trouble encoding this visual and spatial information into long-term memory.

This suggests that the basal ganglia work in both encoding and recalling spatial information.People with Parkinson's disease display working memory impairment during sequence tasks and tasks involving events in time. They also have difficulty in knowing how to use their memory, such as when to change strategies or maintain a train of thought.

Recall: neuroanatomyThe anterior cingulate cortex, globus pallidus, thalamus, and cerebellum show higher activation during recall than during recognition which suggests that these components of the cerebello-frontal pathway play a role in recall processes that they do not in recognition. Although recall and recognition are considered separate processes, it should be noted that they are both most likely constitute components of distributed networks of brain regions.[

According to neuroimaging data, PET studies on recall and recognition have consistently found increases in regional cerebral blood flow (RCBF) in the following six brain regions: (1) the prefrontal cortex particularly on the right hemisphere; (2) the hippocampal and parahippocampal regions of the medial temporal lobe; (3) the anterior cingulate cortex; (4) the posterior midline area that includes posterior cingulate, retrosplenial (see retrosplenial region), precuneus, and cuneus regions; (5) the inferior parietal cortex, especially on the right hemisphere; and (6) the cerebellum, particularly on the left.[

Factors that affect recall

AttentionThe effect of attention on memory recall has surprising results. It seems that the only time attention largely affects memory is during the encoding phase . During this phase, performing a parallel task can severely impair retrieval success.It is believed that this phase requires much attention to properly encode the information at hand, and thus a distractor task does not allow proper input and reduces the amount of information learned.

MotivationMotivation is a factor that encourages a person to perform and succeed at the task at hand. It can be in the form of presented incentive, or personal fear of failure.Any form of motivation thus generally leads a person to better recall. In an experiment done by Roebers, Moga and Schneider (2001), participants were placed in either forced report, free report or free report plus incentive groups. In each group, they found that the amount of correct information recalled did not differ, yet in the group where participants were given an incentive they had higher accuracy results.This means that presenting participants with an encouragement to provide correct information motivates them to be more precise.

InterferenceIn the absence of interference, there are two factors at play when recalling a list of items: the recency and the primacy effects. The recency effect occurs when the short-term memory is used to remember the most recent items, and the primacy effect occurs when the long-term memory has encoded the earlier items. The recency effect can be eliminated if there is a period of interference between the input and the output of information extending longer than the holding time of short-term memory (1530 seconds). This occurs when a person is given subsequent information to recall preceding the recall of the initial information.[48] The primacy effect, however, is not affected by the interference of recall. The elimination of the last few items from memory is due to the displacement of these items from short term memory, by the distracting task. As they have not been recited and rehearsed, they are not moved into long-term memory and are thus lost. A task as simple as counting backwards can change memory recall; however an empty delay interval has no effect.[49] This is because the person can continue to rehearse the items in their working memory to be remembered without interference

ContextContext-dependency effects on recall are typically interpreted as evidence that the characteristics of the environment are encoded as part of the memory trace and can be used to enhance retrieval of the other information in the trace.[52] In other words, you can recall more when the environments are similar in both the learning and recall phases. Context cues appear to be important in the retrieval of newly learned meaningful information. In a classic study by Godden and Baddelley (1975), they demonstrated that deep-sea divers recalled their training more effectively when trained underwater, rather than being trained on land.[53] An academic application would be that students may perform better on exams by studying in silence, because exams are usually done in silence

State-dependent memoryState-dependent retrieval is demonstrated when material learned under the influence of a drug is best recalled in that same drug state. A study by Carter and Cassady (1998) showed this effect with antihistamine.[55] In other words, if you study while on hay fever tablets, then you will recall more of what you studied if you test yourself while on antihistamines in comparison to testing yourself while not on antihistamines after having studied on antihistamines.A study by Block and Ghoneim (2000) found that, relative to a matched group of healthy, non-drug-using controls, heavy marijuana use is associated with small but significant impairments in memory retrieval.[56]Cannabis induces loss of internal control and cognitive impairment, especially impairment of attention and memory, for the duration of the intoxication period.[57]Stimulants, such as cocaine, amphetamines or caffeine are known to improve recall in humans.[58] However, the effect of prolonged use of stimulants on cognitive functioning is very different from the impact on one-time users. Some researchers have found stimulant use to lower recall rates in humans after prolonged usage

GenderConsistently, females perform better than males on episodic memory tasks including delayed recall and recognition. However, males and females do not differ on working, immediate and semantic memory tasks. In general, neuro-psychological observations suggest that anterior lesions cause greater decits in females than in male. It has been proposed that the gender differences in memory performance reect underlying differences in the strategies used to process information, rather than anatomical differences. However, gender differences in cerebral asymmetry received support from morphometric studies showing a greater leftward asymmetry in males than in females, meaning that men and women use each side of their brain to a different extent.[59] There is also evidence for a negative recall bias found in women, which means females in general are more likely than males to recall their mistakes.[60] In a eyewitness study done by Dan Yarmey (1991) from the University of Guelph, he found that women were significantly more accurate than men in accuracy of recall for weight of suspects

PhenomenaThe phenomenological account of recall is referred to as metacognition, or "knowing about knowing". This includes many states of conscious awareness known as feeling-of-knowing states, such as the tip-of-the-tongue state. It has been suggested that metacognition serves a self-regulatory purpose whereby the brain can observe errors in processing and actively devote resources to resolving the problem. It is considered an important aspect of cognition that can aid in the development of successful learning strategies that can also be generalized to other situations.[62]

The cerebellum (Latin for little brain) is a region of the brain that plays an important role in motor control. It is also involved in some cognitive functions such as attention and language, and probably in some emotional functions such as regulating fear and pleasure responses.[

Its movement-related functions are the most clearly understood, however. The cerebellum does not initiate movement, but it contributes to coordination, precision, and accurate timing.

It receives input from sensory systems and from other parts of the brain and spinal cord, and integrates these inputs to fine tune motor activity.[ Because of this fine-tuning function, damage to the cerebellum does not cause paralysis, but instead produces disorders in fine movement, equilibrium, posture, and motor learning

cerebellum

Cerebellum

The cerebellumThe cerebellum ("little brain") is a structure located at the rear of the brain, near the spinal cord It looks like a miniature version of the cerebral cortex, in that it has a wavy, or convoluted surface.

Unlike the hippocampus which is involved in the encoding of complex memories, the cerebellum plays a role in the learning of procedural memory, and motor learning, such as skills requiring co-ordination and fine motor control.An example of a skill requiring procedural memory would be playing a musical instrument, or driving a car or riding a bike.

Individuals with transient global amnesia that have difficulty forming new memories and/or remembering old events may sometimes retain the ability to perform complex musical pieces, suggesting that procedural memory is completely dissociated from conscious memory, also known as explicit memory

This separation makes sense if the cerebellum, which is far removed from the hippocampus, is responsible for procedural learning.

The cerebellum is more generally involved in motor learning, and damage to it can result in problems with movement, specifically it is considered to co-ordinate timing and accuracy of movements, and to make long-term changes (learning) to improve these skills

Based on surface appearance, three lobes can be distinguished in the cerebellum, called the flocculonodular lobe, anterior lobe (above the primary fissure), and posterior lobe (below the primary fissure). ")

These lobes divide the cerebellum from rostral to caudal (in humans, top to bottom). In terms of function, however, there is a more important distinction along the medial-to-lateral dimension. Leaving out the flocculonodular part, which has distinct connections and functions, the cerebellum can be parsed functionally into a medial sector called the spinocerebellum and a larger lateral sector called the cerebrocerebellum.A narrow strip of protruding tissue along the midline is called the vermis (Latin for "worm

The smallest region, the flocculonodular lobe, is often called the vestibulocerebellum. It is the oldest part in evolutionary terms (archicerebellum) and participates mainly in balance and spatial orientation; its primary connections are with the vestibular nuclei, although it also receives visual and other sensory input. Damage to it causes disturbances of balance and gait.[

The medial zone of the anterior and posterior lobes constitutes the spinocerebellum, also known as paleocerebellum. This sector of the cerebellum functions mainly to fine-tune body and limb movements. It receives proprioception input from the dorsal columns of the spinal cord (including the spinocerebellar tract) and from the trigeminal nerve, as well as from visual and auditory systems. It sends fibres to deep cerebellar nuclei that, in turn, project to both the cerebral cortex and the brain stem, thus providing modulation of descending motor systems.

The lateral zone, which in humans is by far the largest part, constitutes the cerebrocerebellum, also known as neocerebellum. It receives input exclusively from the cerebral cortex (especially the parietal lobe) via the pontine nuclei (forming cortico-ponto-cerebellar pathways), and sends output mainly to the ventrolateral thalamus (in turn connected to motor areas of the premotor cortex and primary motor area of the cerebral cortex) and to the red nucleus.

There is disagreement about the best way to describe the functions of the lateral cerebellum: It is thought to be involved in planning movement that is about to occur, in evaluating sensory information for action, and in a number of purely cognitive functions as well.

Prior to the 1990s, the function of the cerebellum was almost universally believed to be purely motor-related, but newer findings have brought that view strongly into question. Functional imaging studies have shown cerebellar activation in relation to language, attention, and mental imagery; correlation studies have shown interactions between the cerebellum and non-motoric areas of the cerebral cortex; and a variety of non-motor symptoms have been recognized in people with damage that appears to be confined to the cerebellum.

The cerebellum, Doya proposes, is best understood as a device for supervised learning, in contrast to the basal ganglia, which perform reinforcement learning, and the cerebral cortex, which performs unsupervised learning.

There is considerable evidence that the cerebellum plays an essential role in some types of motor learning.