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Scanning Headset


The Nervous System


Fast communication system

Central NS - Brain and spinal cord

Peripheral NS - Autonomic (Sympathetic & Parasympathetic NS) & Somatic NS

Autonomic NS - Not under conscious control, unmyelinated neurons, motor pathways only

Somatic NS - Consciously directed movement, myelinated neurons, motor & sensory pathways

Parasympathetic NS - slows down the NS back to rest and digest

Sympathetic NS - prepares the body for fight or flight

The Endocrine System


Slower communication system

Glands released hormones which travel in the bloodstream



Testes - Testosterone - Regulate males sex characteristics

Ovaries - Oestrogen - Regulates menstrual cycle

Adrenal medulla - Adrenaline - Prepares body for fight or flight

Pituitary gland - melatonin - sleep

Hemispheric lateralisation


Each hemisphere dominant for specific functions e.g.. left = lang.

Contralateral control

Sperry (1968) - 11 split brain patients, divided field method

If info presented to RVF ppts could say it as language centres in LH

If info presented to the LVF cannot say it but can select item with left hand

When shown a nude to RH - giggled but said they did not see anything

Conclusion: LH - language centres RH - emotional & spatial tasks


+ High control

- Low external validity

- Age differences (Szaflarski)

- Modern research disconfirms earlier findings - Case study JW

Circadian Rhythms


Biological rhythm that lasts 24 hrs

e.g. sleep-wake cycle

Endogenous pacemaker (internal mechanism) e.g. SCN

Exogenous zeitgeber (external influences) e.g. light/ dark

SCN sends messages to pineal gland, when dark increase in melatonin = sleepy

Siffre (cave study) - 6 mths, free running cycle 25 hrs


+ Reliable finding: Aschoff & Wever (bunker study), Folkard (sped up clock)

- Methodological limitations (Siffre)

+ Real life application: circadian trough at 6am

- Individual differences (Duffy) Morning people

Structure and function of neurons


All neurons have:

Cell bodies (with a nucleus) - control centre

Dendrites - receive messages from nearby neurons

Axon - transmits the action potential to the axon terminal

Motor - carry info from CNS to effectors, long axons, short dendrites

Relay - carry info between neurons, short axons & dendrites

Sensory - carry info from receptors to CNS, short axons, long dendrites

Fight or Flight Response


NS & endocrine system working together

The amygdala alerts the hypothalamus

This triggers the sympathetic branch of NS (sympathomedullary pathway)

This activates the adrenal medulla to release adrenaline

This prepares the body for fight or flight


- Individual differences: Taylor suggests females tend & befriend

- Incomplete explanation: Gray introduced 'Freeze'

- Unhelpful for today's modern cognitive stressors

Plasticity & Functional Recovery


During infancy neural connections grow rapidly

Neural pathways strengthen

Synaptic pruning if not used

Plasticity: the brain adapts due to experience e.g. Maguire (taxi)

and learning e.g. Draganski

Functional recovery: recovery after trauma

Neural regeneration - new neurons/ connections formed

Neural reorganisation

Structural changes e.g. blood vessels & axonal sprouting

Recruitment of homologous areas


+ Golf training 40-60yrs (Bezzola)

+ Maguire - strong evidence +ve correlation: time & size

- Individual; differences - more likely recover with more education

- Maladaptive changes e.g. phantom limb syndrome

Infradian & Ultradian Rhythms


Infradian rhythms: last longer tan 24 hours e.g. menstrual cycle

Rising oestrogen = egg release

Rising progesterone = thick womb

Exogenous Zeitgebers: McClintock & Stern - effects of pheromones in 29 women

SAD: 'Winter blues' may be caused by hormone melatonin

Ultradian rhythms: more than one every 24hrs e.g. sleep stages

Stage 1&2: Light sleep, alpha waves sleep spindles

Stage 3&4: Deep sleep

Stage 5 (REM): Theta waves, dreaming


Methodology of menstrual cycle studies e,g, confounding variables

+ Evolutionary basis of menstruating together

+ Dement & Kleitman - sleep study

- Individual differences in sleep

Synaptic transmission


The action potential travels down the axon of pre-synaptic neuron

The vesicles migrate and bind to the membrane

Neurotransmitters are released and diffuse across the synapse

They bind to receptors like a lock and key and have inhibitory (IPSP) or excitatory (EPSP) effects

Neurotransmitters are released and are reabsorbed (reuptake) or metabolised (broken down)

Summation - the process of adding together the IPSPs & EPSPs

Localisation of Function


Specific areas of the brain are responsible for specific actions

Opposite is a holistic theory

Frontal lobe - higher order thinking

Motor cortex - motor movement

Temporal lobe - auditory info

Occipital lobe - visual info

Parietal lobe - perception

Somatosensory cortex - info from touch

Broca's area - speech production

Broca's aphasia - speech slow, laborious and lacks fluency

Wernicke's area - language comprehension

Wernicke's aphasia - 'word salad'


- Lashley - holistic theory of equipotentiality (10-50% rats cortex)

- Individual differences: Harasty - women larger Broca's areas

+ HM - hippocampus responsible for transferring STM to LTM

+ Brain scan evidence - episodic memories right / semantic memories left pre frontal cortex

Ways of Studying the Brain

AO1 fMRI: detects changes in blood deoxygenation, 3D images

AO3 + High spatial res

low temporal res & costly

AO1 EEG: Measures electrical activity using nodes, brain wave patterns

AO3 + High temporal res

- Low spatial resolution

AO1 ERP: Like EEG but statistical analysis to just leave the response to the stimulus

AO3 + High temporal res & more specific info

- Lack of standardisation

AO1 Post mortem: Study brain after death, compare to a neuro typical brain

AO3 + Medical research, historically useful e.g. Broca, Wernicke

+ Correlational data & ethics

Endogenous Pacemakers & Exogenous Zeitgebers


EP: SCN bundle of nerve fibres, regulates sleep

Ralph (1990) Mutant hamster study SCN cells transplanted and developed 20hr cycles 

DeCoursey (2000) SCN cells destroyed of wild chipmunks, many killed within 80 days

EZ: external factors - entrain EPs

Light major EZ: Campbell & Murphy - light to ppt legs in night

Social cues e.g. meals

De-synchronisation - EP is not in time with EZ e.g. jet lag


- Issues - animal extrapolation

- Lack of replication of C&M

- Contradictory research of EZ - Miles blind man 25hr cycle

- Innuit Indians in Arctic circle have consistent sleep patterns


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