Psychology - Biopsychology

What are the divisions of the nervous system

1. Nervous system

2. CNS

3. Peripheral nervous system

4. Autonomic and somatic nervous system

5. sympathetic and parasympathetic nervous system

What are the functions of the nervous system

• Consists of CNS and PNS and communicates via electrical signals.

• fast acting and short term effects

• Two roles:

• Processes and responds to information from the environment

• Coordinates the working of different glands and organs

What is the CNS

• involves complex processing

• consists of the brain (responsible for conscious and most unconscious processing)

• consists of spinal cord (receives and transmits information and some reflex processing)

What is the PNS

• neurones transmit impulses to and from CNS

• sensory - to CNS

• motor - away from CNS

What is autonomic nervous system

• unconscious, involuntary system

• governs vital functions in the body such as breathing and heart rate

What is somatic nervous system

• conscious, voluntary system

• governs muscle movement and receives information from sensory receptors

What is sympathetic and parasympathetic nervous system?

• S → increases bodily functions, releases adrenaline to prepare body for fight or flight, increases heart rate and breathing rate, dilates pupils and inhibits digestion and saliva production

• PS → decreases bodily functions, decreases heart and breathing rate, contracts pupils and stimulates digestion and saliva production

What is the endocrine system

• It instructs glands to release hormones which act on target cells

• Communicates via chemicals

• It acts slowly but has widespread and long-term effects

Outline the fight or flight response

• The body senses a stressor and the amygdala reacts

• The amygdala sends signals to the hypothalamus which activates the sympathetic nervous system, and the adrenal medulla releases adrenaline

• Adrenaline induces sympathetic state which causes changes such as: increased heart and breathing rate, dilated pupils and inhibited digestion and saliva production

Structure and function of sensory neurone

• long dendrites and short axon

• unipolar → only one process extends from cell body

• detects sensations from sensory site and sends action potential to CNS along myelinated axon

• found in various locations around body

Structure and function of relay neurone

• short dendrites and no myelinated sheath

• found in CNS

• communicator between sensory and motor neurone

Structure and function of motor neurone

• short dendrites and long axon

• begins in CNS and projects to muscles

• detects signal from relay neurone in CNS via synaptic transmission and sends to effector along myelinated axon to contract

Describe the structure and function of a neuron (6)

• neurons enable communication within the nervous system

• the soma in the cell body contains the genetic material

• dendrites extend from cell body and receive information from other neurons

• axons, which can be myelinated to increase speed of transmissions, carry messages away from cell body

• axon terminals contain neurotransmitters

What is a synapse

• junction where 2 neurons meet

What is a neurotransmitter + types

• chemical messages released by neurones

• excitatory → increases likelihood of neurone firing action potential

• inhibitory → decreases likelihood of neurone firing action potential

Outline synaptic transmission

1. Action potential reaches presynaptic neurone, causing it to release vesicles containing neurotransmitters to synaptic gap

2. Neurotransmitters diffuse across synaptic gap and bind to receptors on postsynaptic membrane

3. Postsynaptic neurone releases another impulse along axon

4. Neurotransmitters return to presynaptic neurone via transport proteins via reuptake

What is localisation

theory that specific areas of the brain are associated with certain physical and psychological functions

What lateralisation

theory that certain hemispheres control certain physical and psychological functions

label ts

• blue → frontal lobe

• yellow → parietal lobe

• green → temporal lobe

• red → occipital lobe

Function of frontal lobe & area & cortex

• controls cognitive activity

• Broca’s area (in left frontal lobe) → language production, allows speech to be fluent

• damage leads to Broca’s aphasia → difficulty producing speech

• Motor cortex → controls voluntary movement

• damage leads to loss of movement

Function of parietal lobe and cortex

• processes sensory information and directs movement

• Somatosensory cortex → processes sensory information from skin

Function of temporal lobe and area

• processes auditory information and understanding speech

• Wernicke’s area → language understanding, allows speech to be meaningful

• damage leads to Wernicke’s aphasia → difficulty understanding language, but can produce it

Function of occipital lobe and cortex

• processes visual information

• Visual cortex → Each eye sends information from right visual field to left visual cortex and vice versa

AO3 for Localisation of function in the brain

✅Evidence from neurosurgery → cingulotomy isolates part of brain responsible for OCD

✅Evidence from brain scans → dual tasks show Broca and Wernicke’s areas are responsible for language during reading task and listening task

❌Language may not be localised to just Wernicke and Broca’s areas

❌Lateralisation is supported by case studies such as Phineas Gage

What is split brain research

the study of individuals whose corpus callosum have been severed