General Psychology General Psychology (PY110)(PY110)

Chapter 2

Neuroscience

Neuroscience and Neuroscience and BehaviorBehavior

All sensory organs – Receptors

Muscles and Glands – Effectors

Neurons – Communication channel

The Structure of a NeuronThe Structure of a Neuron

How Neurons How Neurons CommunicateCommunicate

Communication within

a neuron is electrical

Communication within

a neuron is electrical

Communication between

neurons is chemical

Communication between

neurons is chemical

Types of NeuronsTypes of Neurons

Interneurons exist only in the central nervous system

Sensory neurons carry information to the central nervous system from sensory receptors in the eyes, muscles, and glands

Motor neurons carry movement commands from the central nervous system to the rest of the body

Neurotransmitters, Neurotransmitters, Drugs, and PoisonsDrugs, and PoisonsKey terms:

AgonistsAgonists AntagonistsAntagonists

Drugs and poisons that increase the activity of one or more neurotransmitters

Drugs and poisons that decrease the activity of one or more neurotransmitters

NeurotransmittersNeurotransmitters

1.Acetylcholine (ACh) is involved in both learning and memory and muscle movement

2.Dopmaine impacts our arousal and mood states, thought processes, and physical movement

3.Serotonin and norepinephrine are neurotransmitters involved in levels of arousal and mood, and play a major role in mood disorders such as depression

4.GABA is the main inhibitory neurotransmitter in the nervous system; glutamate is the main excitatory neurotransmitter

5.Endorphins are a group of neurotransmitters that are involved in pain perception and relief

DopamineDopamine

Low levels are associated with Parkinson’s disease, and excessively high levels are associated with schizophrenia

L-Dopa is an agonist that increases production of dopamine

Anti-psychotic drugs are antagonists that block the receptor sites for dopamine so that this neurotransmitter cannot send its messages

Amphetamine acts as an agonist by stimulating the release of dopamine from axon terminals

Cocaine is an agonist that blocks the re-uptake of dopamine

Nervous System Nervous System SubdivisionsSubdivisions

The Central Nervous The Central Nervous SystemSystemConsists of the spinal cord and the brain

◦The spinal cord has two functions Conduit for incoming sensory

data and outgoing movement commands

Provides for spinal reflexes, which are simple automatic actions not involving the brain

◦The brain is the control center for the entire nervous system

The Peripheral Nervous SystemThe Peripheral Nervous System

Consists of two parts:◦ The somatic (or skeletal) nervous system

carries sensory input from receptors to the CNS and relays commands from the CNS to the skeletal muscles to control their movement

◦ The autonomic nervous system regulates our internal environment and consists of two parts The sympathetic nervous system is in control

when we are very aroused and prepares us for defensive action (such as running away or fighting)

The parasympathetic nervous system is in control when the aroused state ends to return our body to its normal resting state

Components of EmotionComponents of Emotion

An emotion is a complex psychological state that involves three components:

An emotion is a complex psychological state that involves three components:

PhysicalPhysical BehavioralBehavioral CognitiveCognitive

A physiological state of arousal triggered by the

autonomic nervous system

An outward expression including facial expressions,

movements and gestures

An appraisal of the situation to determine which emotion we are experiencing and how

intensely

•James-Lange Theory

•Cannon-Bard Theory

•Schachter-Singer Theory

Emotion Theory Emotion Theory ComparisonComparison

Stimulus:Sight of bear

Stimulus:Sight of bear

Stimulus:Sight of bear

Physiological Arousal

Emotional Response

(Fear)

Emotional Response

(Fear)

Emotional Response

(Fear)

Physiological Arousal

Physiological Arousal

The Central Core Brain Structures

The Limbic System

The Four Lobes and the The Four Lobes and the Sensory-Motor Processing AreasSensory-Motor Processing Areas

The Case of Phineas GageThe Case of Phineas Gage

Phineas Gage was railroad worker who survived when a metal tamping iron flew through his left cheek and head, exiting through his frontal lobes

He became irresponsible, impulsive, disorderly, indecisive, and cursed, leading neuroscientists to think the frontal lobes are important in such behaviors

LanguageLanguage

What we know…What we know…Left hemisphere

◦ Language◦ Math and logic skills◦ More analytical,

analyzing wholes intopieces

Right hemisphere◦ Spatial perception◦ Solving spatial

problems◦ Drawing◦ Face recognition

A band of neurons called the Corpus Callosum joins the two hemispheres ◦ Allows communication and coordinates

functions

Five Five Stages Stages of Sleepof SleepBrain wave taken by Electroencephalogram (EEG)

SleepSleepCyclesCycles

•Cycles last about 90 minutes.•4-6 cycles each night

Nature of Sleep & DreamsNature of Sleep & Dreams

2 Types of Sleep – REM and Non-REM Non-REM = Quantity REM = Quality REM Sleep reduced by alcohol and sleeping pills Sleep Deprivation (or Dream Deprivation)

◦ Moderate – Sleep rebound◦ Severe – depression, impaired memory, decreased immune response

Circadian cycles – Biological clock

Sleep (Hrs)

Awake (Hrs) % REM

Adults 8 16

Babies 16 8

Stage

Wave Form

Remarks

Non –REM

1 Alpha & Theta

‘Falling’ asleep

2 Theta Light sleep

3 Delta Deep Sleep- Night terrors, Sleep walking, Sleep talking, Etc.

4 Delta

3 Delta

2 Theta Light sleep

REM Paradoxical Sleep - Dreaming occurs