INTRODUCTION TO THE BRAIN

Outline

Nervous System Orientation of the Brain Ways to Divide the Brain

Lobes Evolutionary

Forebrain Prosencephalon Diencephalon Telencephalon

Structure of the Vertebrate Nervous System

Neuroanatomy Anatomy of the nervous system Study of the various parts of the nervous

system and their respective function(s)

Nervous system consists of many substructures, each comprised of many neurons

Nervous System

Brain Spinal cord

Somatic Nervous System

Autonomic Nervous System Sympathetic

Nervous System Parasympathetic

Nervous System

Central Nervous System Peripheral Nervous System

Brain Orientation

Brain Orientation

Sagittal

Coronal

Horizontal

Brain Orientation

Rostral Caudal Ventral Dorsal

Anterior Posterior Inferior Superior

DIVISION OF THE BRAIN

FOREBRAIN

Cerebral Cortex

Cerebral Cortex

Divided into 4 lobes

Frontal Parietal Occipital Temporal

Cerebral Hemispheres

Motor and Somatosensory Cortices

Primary Motor Cortex Primary Somatosensory

Cortex

Somatosensory Homunculus

Primary Motor Cortex

FOREBRAIN

Prosencephalon

Basal Forebrain

Cholinergic output of the CNS Nucleus basalis

Arousal, wakefulness, attention

FOREBRAIN

Diencephalon

Thalamus

Sensory relay

“Gateway to the cortex”

Hypothalamus

Homeostasis

Endocrine Function

Anterior Pituitary

Adenohypophysis

Adrenocorticotropic hormone (ACTH)

Thyroid-stimulating hormone (TSH)

Prolactin Gonadotropins

Follicle-stimulating hormone (FSH)

Luteinizing hormone (LH)

Posterior Pituitary

Neurohypophysis

Oxytocin Milk let-down Maternal care

Vasopressin or Anti-diuretic hormone Water retention

FOREBRAIN

Telencephalon

Limbic System

Amygdala

Hippocampus

Amygdala

Directly connected to the olfactory bulb and the hippocampus

Important in emotion

Fear response

Hippocampus

Important in memory and learning

Alzheimer’s Disease Destruction of

hippocampal neurons

Symptoms include memory loss, neurofibrillary tangles, and amyloid plaques

Miosis

Miosis

4 Hypotheses for the Development of AD Demyelination Hypothesis

Cholinergic Hypothesis

Amyloid Beta Hypothesis

Tau Hypothesis

AD- Demyelination Hypothesis

Cortex shrivels

Hippocampus shrinks

Ventricles fill with fluid

AD- Amyloid Beta and Tau

Fewer neurons

Fewer synapses

Tangles

Plaques

AD- Tau Hypothesis

Progression of Alzheimer’s Disease

Treatments

Early stages

Mild to moderate stages

Severe stages

Alzheimer’s Disease