Biopsychology

Central nervous system

Brain, spinal cord

Brain

Occipital, temporal, parietal, frontal lobe

Occipital lobe

Visual information

Temporal lobe

Auditory information

Parietal lobe

Spatial navigation

Frontal lobe

Logical, reasoning, planning

Spinal cord

Transfer between brain and body, simple reflexes

Peripheral nervous system

Replay information between CNS and body

Somatic nervous system

Communicate CNS and environment, sensory and motor neurons, skeletal muscles

Autonomic nervous system

Homeostasis, maintain internal processes, motor neurons, smooth muscle and glands

Sympathetic nervous system

Fight/flight, increase heart hate, blood pressure, breathing, to organs

Parasympathetic nervous system

Restore body to normal

Motor neuron

info from CNS to muscle/glands in PMS, lower spine to muscle, upper brain and spine

Neurons

Send signals using neurotransmitters in the brain to body

Relay neuron

in CNS, pass info from sensory to motor neuron, short distance no myelin sheath

Sensory neuron

info from receptor in SNS to CNS, psychounipolar, axon 2 extension, cell body in middle

Reflex arch

Stimuli - Receptor - Sensory Neuron - Relay Neuron - Motor Neuron - Gland/muscle

Endocrine system

a network of glands across the body that secrete hormones in the blood to target cells

Hypothalamus

connected to pituitary gland and controls release of its hormones

Pituitary gland

master gland, hormone released stimulates release of other hormones

Anterior lobe

release ACTH stimulates adrenal cortex and cortisol

Posterior lobe

release oxytocin causing uterus contraction

Pineal gland

release melatonin responsible for biological rhythms

Thyroid gland

release thyroxine responsible for regulating metabolism

Adrenal gland

Above kidneys, adrenal medulla and adrenal cortex

Adrenal medulla

inside, release adrenaline and noradrenaline for fight/flight

Adrenal cortex

outside, release cortisol stimulating glucose release and supress immune system

Testes

release androgens, testosterone, for puberty and muscle growth

Ovaries

release oestrogen for regulating reproductive system (menstrual cycle and pregnancy)

Synaptic transmission

Nerve impulses passed over synaptic gap

Neurotransmitter

Chemicals realised from synaptic vesicle into synapse which affect transfer of impulse. They are broken down by enzyme or reuptake after

Action potential

Neuron sends info from cell body down axon as electrical activity causing resting potential to move forward. It diffuses across synaptic cleft to post synaptic cell

Excitatory

Synaptic connection which increases likelihood of next neuron firing based on action or NT at post synaptic receptor (accelerator)

Inhibitory

Synaptic connection which decreases likelihood of next neuron firing based on action or NT at post synaptic receptor (brake)

Synaptic transmission process

Nerve impulse in axon reach synaptic terminal which trigger NT release into synaptic gap. NT bind to adjacent dendrite receptors and is taken up by post synaptic neuron where message is passed along by electrical impulses.

Fight/flight response

CNS perceive stress, sympathetic NS actives response, adrenal gland produce adrenaline and cortisol causing increase heart rate, breathing and stops digestion. Stress over, parasympathetic NS takes over resume digestion and reduce heart rate/breathing.

Taylor et al

Women more flight than fight/flight as they have higher oxytocin. They prefer ‘tend and befriend’

Van Dawes et al

Study during 9/11 found high human connection and greater cooperation between men and women. People don’t necessarily act on fight/flight when stressed.

Lee and Harley

Genetic basis for fight/flight, SRY gene on Y chromosome promotes aggression so men may react differently to stress than women.

Localisation of function

Certain functions have certain locations within the brain

Motor area

Frontal lobe, controls voluntary movements in muscles, contralateral brain

Somatosensory area

Parietal lobe, receive sensory info from skin and produces pressure, pain, temperature. Different parts receive messages from different locations

Visual area

Occipital lobe, different parts processing different info (colour, shape, movement)

Auditory area

Temporal lobe, acoustic info, primary area processes simple features of sound (loudness, pitch)

Brocas area

Left frontal lobe responsible for speech production

Wernickes area

Left temporal lobe responsible for language comprehension

Lashley

Equipotentiality theory, basic motor and sensory are localised but intact areas of context can take responsibility for some cognitive functions after injury, brain damage by extent not location

Gage

Iron went through skull damaging frontal cortex, led to loss of inhibition and anger

Dronkers et al

Brocas patients re-examined found other areas contributed to reduced speech ability not just Brocas

Hemispheric lateralisation

2 halves of the brain operates differently with specialisation for function

Left hemisphere

Language dominant, RVS, Broca, Wernicke

Right hemisphere

Visual motor tasks, LVS

Corpus callosulm

Connects hemispheres through nerve fibres allowing communication between them, commissurotomy severs this

Sperry and Gazzaniga

Use split brain patients to examine extent to which extent hemispheres are specialised linking visual fields (opposite to hemisphere) to tasks

Describe what you see

Patients shown image and asked to describe it

Tactile test

Patients given object and asked to describe feel and chose an alternative similar object

Drawing test

Patients shown word and asked to draw it in opposite hand to VF

LH results

Describe what you see, describe object feeling, identify alternative object

RH results

Identify alternative object, draw clear picture regardless of dominant hand

Andrewes

Commissarotary is rare, patients previously had physical disorders, unrepresentative, temporal validity, confounding variable

Rogers et al

Chickens brain lateralisation associated with enhanced ability to perform simultaneous tasks

Patient JW

Able to speak out of RH after using LVS despite RH responsible for visual motor skills

Szaflarski et al

Language becomes more lateralised to LH from children to adolescence but 25+ decreases with age

fMRI

measures blood activity with haemoglobin and deoxyhaemoglobin, 1-4 sec, 1-2mm, non invasive

EEG

measure electrical activity with electrodes, 1-10ms, superficial general region, used to detect epilepsy, non evasive

ERP

measure electrical activity at stimulus using electrodes, 1-10ms, superficial general region

Post Mortem Examination

physical examination of brain after death, in depth study,

fMRI con

cant directly measure neural activity

Post Mortem con

deficit displayed in lifetime may not be linked to physical deficit

EEG con

electrical activity not always in exact area

ERP pro

determines how processing is affected by specific experimental manipulation

Plasticity of the brain

Brain physically changes and develops new neuron pathways with new experience, lots of synapses in youth, decrease with age

Synaptic pruning

Removing of unused synapses

Boyke et al

60yrs learn to juggle creates more grey area, when stoped it decreased

Kuhn et al

Play Mario 30 min/day for 2 months compared to control, increase hippocampus

Davidson et al

8 meditators compared to 10 volunteers, greater activation of gamma waves

Kempermann et al

Rats in cages with stimulation had greater hippocampus to simple cages but not generalisable to humans

Maguire

MRI scan posterior hippocampus of London taxi drivers to control. Larger hippocampus, volume positively correlated to experience, correlation not causation, possibly naturally large hippocampus led to job success

Functional recovery

recovery of abilities and processes lost due to brain injury or disease

Stroke patients

1960s stroke patients brains were able to rewire and regain function

Neuronal unmasking 

dormant synapses always exist just inactive, when brain is damaged they receive input and activate 

Axonal pathways

new nerve endings grow and connect to undamaged cells creating new pathways

Homologous area

opposite equal hemisphere take on function of damaged area, eg. JW

Stem cells

replace, regrow or create new neural networks 

Tajiri et al

brain injured rats randomly assigned to stem cell or solution condition, 3mth later stem cells migrate to injury and show development

Elbert et al

neural reorganisation greater in children than adults, there are individual differences in functional recovery, too simplistic

Schneider et al 

patients with college education 7x more likely to recover within a year, 214/769 patients disability free in 1yr, 40% 16+ yrs education 

Neurorehabilitation

spontaneous recovery can happen but slows after a few weeks, physical therapy (movement, electrical) can help counter motor/cognitive deficits