Biopsychology

What is the nervous system and what does it consist of?

The nervous system is a network of cells and communicates using electrical signals

Collects, processes and responds to information in environment

Coordinates working of different organs and cells in body

Consists of brain and spinal cord

What is the nervous system divided into?

1.)Central nervous system

2.)Peripheral nervous system

What is the central nervous system responsible for?

Responsible for controlling our movements and thoughts

How many hemispheres does the brain have and what does it do?

2

Centre of all thought and conscious awareness

What does the spinal cord do?

Responsible for reflex actions i.e.pulling hand away from something hot

What is the peripheral nervous system and what is it divided into?

Transmits messages via neurons to and from CNS

Divided into autonomic nervous system(ANS)and somatic nervous system(SNS)

What does the ANS do?

Governs breathing, heart rate, digestion and stress

What does the SNS do?

Controls muscle movements and receives information from sensory receptors

What is the ANS further divided into?

The sympathetic nervous system and the parasympathetic nervous system

What is the function of the sympathetic nervous system?

Prepares body for intense, physical activity ‘fight or flight’ by increasing heart rate and blood pressure

What is the function of the parasympathetic nervous system?

Manages ‘rest and digest’ functions that calm the body after stress

Draw the divisions of the nervous system on a diagram

What does the endocrine system do?

Works alongside nervous system controlling vital functions in the body

Can have very powerful effects but works more slowly than nervous system at 2/3s compared to 0.25s response in nervous system

How does the endocrine system communicate?

Chemical signals (nervous system is electrical)

What does it instruct glands do?

To release hormones into bloodstream and carry them towards organs i.e. thyroid gland produces thyroxine increasing heart rate and therefore affecting growth rate.

What does the pituitary gland release?

Adrenocorticotrophic hormone(ACTH)/ oxytocin

What does the thyroid gland release?

Thyroxine

What does the adrenal gland release?

Adrenaline

What do the ovaries release?

Oestrogen

What do the testes release?

Testosterone

Why is the pituitary gland known as the ‘master gland’?

Controls release of hormones from other endocrine glands in body

One of first parts of brain to evolve

When do the endocrine system and the autonomic nervous system work together?

When there is a stressful event ‘fight of flight’ response

What happens to the ANS when there is an acute stressor?

Changes from parasympathetic to sympathetic

What does the pituitary gland release and what effect does this have on the adrenal gland?

ACTH and adrenal gland releases adrenaline into bloodstream

What changes happen in the body following the release of adrenaline?

Increased heart rate and breathing rate, pupils are dilated, digestion is inhibited

What happens when the threat has passed?

Parasympathetic nervous system returns body to resting state

Parasympathetic nervous system acts as a brake and reduces activities of body that were increased by actions of sympathetic branch-’rest and digest'

Give 3 evaluation points for ‘fight or flight’

1.)Gray(1988) suggests that first response to danger not to fight or flight but to avoid confrontation and ‘freeze’. Response not taken into account, does not provide explanation for why freeze may occur-doesn’t explain cognitive factors underpinning human response to danger.

2.)Taylor et al(2000) suggests women are more likely to protect offspring and form alliances with other women, rather than fight an adversary or flee-prompted more recent research which has provided an alternate explanation applicable to females.

3.)Modern day life rarely requires such an intense biological response and repeated activation of fight or flight response can have negative consequence on health i.e. raised blood pressure-activation of response can increase blood pressure can contribute to heart disease. Response is maladaptive in everyday life

What is the function of adrenaline in the ‘fight or flight’ response?

-Adrenaline secreted from adrenal medulla into bloodstream

-Heart rate increases to increase blood flow to organs and movement of adrenaline around body

-Pupils dilate to increase light entry to eyes and reduction in functioning of non-essential functions i.e.digestive system to increase energy supply to other essential functions

What are 2 ways of measuring stress?

1.)Checking size of adrenal gland which becomes enlarged under prolonged stress

2.)Checking levels of cortisol in urine

What does the sensory neuron do and what does it consist of?

Carries messages from PNS to CNS

Long dendrites and short axons

What does the relay neuron do and what does it consist of?

Connects sensory neurons to motor neurons

Short dendrites and short axons

What does the motor neuron do and what does it consist of?

Connects CNS to muscles and glands

Short dendrites and long axons

What do neurons do?

Give nervous system means of communication-basis of nervous system

How do neurons transmit signals?

Electrically and chemically

Draw a neuron-basic structure

What are dendrites?

Branch like structures which protrude from cell bod

What is the cell body?

Includes nucleus, which contains genetic material of cell

What are axons?

Carry impulses away down neuron. Covered in a fatty layer of myelin sheath, speeds up electrical transmission of impulse

What are the nodes of ranvier?

Gaps in the sheath-speed process as impulse jumps across gap

What is synaptic transmission?

Process by which neurons communicate

Sends chemical messages across gap

What are synapses and how do they work?

Small gaps that separate neurons-signals transmitted chemically

When electrical impulse reaches end of neuron (presynaptic terminal) it triggers release of neurotransmitter from sacs (synaptic vesicles)

What are neurotransmitters and how do they work?

Chemicals that diffuse across synapses between neuron and that have specialist functions i.e. acetylcholine is found at each point where a motor neuron meets a muscle.

Once it crosses gap, it is taken up by postsynaptic receptor site-dendrites of next neuron

What is excitation?

Adrenaline causes excitation of post synaptic neuron by increasing positive charge, making it more likely to fire and pass on electrical impulse

What is inhibition?

Seretonin neurotransmitter causes inhibition in receiving neuron-neuron becomes negatively charged and is less likely to fire.

What is a strength of increasing understanding of transmitters?

Has led to development of drugs i.e.prozac-slows down reuptake of seretonin

What are the 6 stages of synaptic transmission?

1.)Electrical signal arrives

2.)Neurotransmitter released

3.)Chemicals cross gap

4.)Signal received

5.)Next cell activated

6.)Signal is cleared

What is localisation of function in the brain theory?

The theory that specific functions/processes are localised in specific locations in the brain i.e. hippocampus strongly implicated in processing of memory

Challenges the idea that the brain is unimodal-holistic theory

How can LOF be measured?

Using brain imaging techniques

1.)fMRI

2.)MRI

3.)PET

What did Broca and Wernicke say?

Cortical specialisation-specific functions in specific locations of brain

How many hemispheres does the brain have and what is it covered by?

2 and a thin layer called the cerebral cortex

What are the different parts of the frontal lobe and their functions?

1.)Motor cortex-responsible for movement 

2.)Prefrontal cortex-responsible for executive functioning

3.)Broca’s area-responsible for speech production

What are the different parts of the temporal lobe and their functions?

1.)Auditory area-responsible for auditory processing

2.)Wernicke’s area-responsible for language comprehension

3.)Hippocampus-responsible for memory and spatial navigation

What are the different parts of the parietal lobe and their functions?

1.)Somatosensory cortex-responsible for touch sensation

Governs body orientation and aids learning in practise of complex movements i.e.writing

What is the principal part of the occipital lobe and its function?

Visual area-responsible for processing visual information and distance perception

Label the different lobes of the brain

Give 3 strengths of localisation theory

1.)Support for theory-Petersen et al 1988 used brain scans to demonstrate how Wernicke’s area was active during a listening task and Broca’s area was active during reading task

Shows that these areas of the brain have different functions

2.)Support for theory-Tulving et al 1994-found semantic and episodic memories are in different parts of prefrontal cortex

3.)Neurosurgical evidence-Walter Freeman developed lobotomy meaning to cut connections in the brain to control aggression, still used for OCD and depression-success of procedures suggests disorders are localised

What is the central sulcus and where is it located in the brain?

-At the front of both parietal lobes is the somatosensory area which is separated from the motor area by central sulcus

-Prominent groove on lateral surface of cerebral hemisphere-separates frontal and parietal lobe

What did Broca and Wernicke identify about the language area?

Language located in the left side of the brain

Broca: Identified small area in left frontal lobe responsible for speech production

Wernicke: Identified an area in the left temporal lobe for understanding language

Give 2 limitations of localisation theory

1.)Lashley’s research-removed parts of cortex in rats-no area shown to be more necessary than another in the learning of a maze

Suggests that some higher cognitive functions are not localised but distributed in a holistic way- learning is too complex to be localised

2.)Dick and Tremblay 2016 found only 2% of modern researchers think that language is controlled by B’s and W’s areas

fMRI’s show function is distributed holistically in brain