PSYC234 Flash Cards

What are the four main parts of a neutron?

Dendrites, soma (cell body), axon and axon terminals

What is the resting membrane potential?

-70mV

What causes depolarisation during an action potential?

Sodium (Na+) enters the neuron

What causes the repolarisation?

Potassium (K+) leaves the neuron

What is the threshold for an action potential?

-55mV

What role does calcium play at the synapse?

Calcium influx triggers neurotransmitter release.

Main excitatory neurotransmitter

Glutamate

Main inhibitory neurotransmitter

GABA

EPSPs

Increase likelihood of firing

Spatial summation

Multiple synapses

What is Hebb's rule?

Neurons that fire together wire together

Habituation

Reduced response after repeated harmless stimulation

Sensitisation

Enhanced response following a strong stimulus

Which animal did Kandel study?

Aplysia

LTP

Long-term potential (strengthening of synapses)

What neurotransmitter is critical for LTP?

Glutamate

Which receptor allows calicum entry during LTP?

NMDA receptor

What happens to AMPA receptors during LTP?

More AMPA receptors are inserted into the synapse.

What is LTD?

Long-term depression (weakening of synapses)

High calcium levels produce what?

LTP

Proliferation

Birth of new neurons

Migration

Movement of neurons to their final destination

Differentiation

Neurons becoming specialised

Synaptogenesis

Formation of synapses

Myelination

Formation of myelin around axons

Apoptosis

Programmed cell death

What does BDNF do?

Promotes neuron survival and growth

What did London taxi drivers demonstrate?

Experience can enlarge the hippocampus

Neuroplasticity

The brain's ability to change with experience

Does neuroplastcity occur only in childhood

No

Benign

Non cancerous

Ischaemic Stroke

Stroke caused by a blocked blood vessel

Encapsulating

grows in membrane

Excitotoxicity

Excess glutamate causing neuron death

Aneurysm

Ballooning of a weakened blood vessel

Concussion

Functional disruption

Coup

damage at impact site

Encephalitis

Brain inflammation

How do neurtoxins damage the nervous system?

By disrupting neurotransmission or killing neurons

Stenosis

Narrowing of arteries

What causes Alzheimer's disease? (3)

Plaques, tangles and acetycholine loss

Which brain area is heavily affected in Alzheimer's?

Hippocampus

What causes Parkinson's disease? (and where)

Dopamine neuron loss in the substantia nigra

Three key Parkinson's symptoms?

Tremor, rigidity, bradykinesia (slowness of movement)

What treatment replaces dopamine?

L-DOPA

What causes Huntington's disease?

excessive CAG repeats on chromosome 4

Chorea

Involuntary jerky movements

What causes multiple sclerosis

Autoimmune destruction of myelin

What causes epilepsy?

Excessive neural firing

Glutamate > GABA is associated with what disorder?

Epilepsy

James-Lange Theory

Physiological arousal precedes emotion

Who identified universal facial expressions?

Ekman

Name Ekman's six universal emotions

Happiness, sadness, fear, anger, surprise, disgust

What is the facial feedback hypothesis?

Facial expressions influence emotions

What brain structure is most associated with fear?

Amygdala

What happened to S.M.

Amygdala damage caused impaired fear

What does the cingulate gyrus do?

Emotional regulation

What does the hypothalamus regulate?

Stress and physiological responses

What brain structure is involved in reward?

Basal ganglia

STM

Short term memory - temporary

explicit memory

active recall, conscious

What happened to H.M.

Hippocampus removed, causing anterograde amnesia

Anterograde amnesia

inability to form new long-term memories

What memory system remained intact in H.M.

Procedural memory

Function of the hippocampus in memory

Formation of long-term memories

Function of prefrontal cortex in memory

Working memory and organisation

Which structure supports procedural memory

Basal ganglia

Which structure supports motor learning

Cerebellum

Which type of memory is most impaired in Alzheimer's

Explicit memory

Motivation

The process that initiates, directs and maintains goal-directed behaviour

Intrinsic motivation

behaviour for enjoyment

Homeostasis

maintaining phsyiological variables within optimal ranges

According to drive reduction theory, what occurs when a biological need is unmet

A drive is created that motivated behaviour to restore balance

Regulatory drives

hunger, thirst, sleep

Where is dopamine primarily produced?

Substantia nigra and ventral tegmental area (VTA)

Major functions of dopamines

Reward, motivation, movement, mood, appetite, memory

Ghrelin

increases hunger

Acquisition

Learning phase where the CS and US are paired

Appetitive conditions

Conditioning using rewarding outcomes

positive contingency

CS reliably predicts the US

Reinforcement

A conseuqnce that increases the likelihood of a behaviour occuring again

Drive reduction theory

Behaviour is reinforced when it reduced a biological drive

Premack Principle

A preferred behaviour can reinforce a less preferred behaviour

Outcome learning

learning the relationship between a bheaviour and its conseuqneces

What characterises goal-directed behaviour

Flexible, deliberate, sensitive to outcome

Characteristics of habitual behaviour

Automatic, stimulus-driven, insensitive to outcomes

Outcome devaluation

Reducing the value of a reward after learning has occured

Specific satiety

A reward becomes less valuable because the individual has had enough of it

How can you distinguish goal-directed from habitual behaviour?

Goal-directed behaviour changes after devlaution; habitual behaviour does not

Placebo

An inactive treatment that can produce improvement through expectation

Nocebo

A harmless treatment or situation that produces negative effects because of expectation

Placebo effect

Real improvement cause by belief rather than the treatment itself

Nocebo effect

Harmful symptoms caused by negative expectations

Can placebos work if participants know they are placebos?

Yes, open-label placebos can still produce benefits

Benefits of placebo effects in healthcare (2)

reduced medication use and lower treatment costs

Nocebo symptoms

Headaches, nausea, worsening symptoms, reduced immune functioning

Psychopathology

scientific study of mental disorders, causes and treatments

5Ds

Deviance, Distress, Dysfunction, Duration and Danger

Biopsychosocial model

Mental disorders result from interacting biological, psychological and social factors

Monoamine hypothesis of depression

Depression is caused by low serotonin and/or noredrenaline