Biopsychology Key Terms

Central Nervous System

Consists of the brain and the spinal cord, is the origin of all complex demands and decisions

Peripheral Nervous System

Transmits messages via millions of nerves to and from the CNS to muscles and glands

Somatic Nervous System

Governs muscle movement and receives information from sensory receptors

Autonomic Nervous System

Governs vital bodily functions (breathing, heart rate, digestion, sexual arousal, stress responses)

Sympathetic Nervous System

Prepares the body for stress-related emergencies by slowing down other bodily processes

Parasympathetic Nervous System

Conserves the body's natural activity and relaxes the individual once the emergency has passed

Neuron

The building blocks of the nervous system, transmit signals electrically and chemically around the body as primary means of communication

Sensory neuron

Carry nerve impulses from receptors to the spinal cord and brain,

Long dendrites short axons

Relay/Interconnecting Neuron

Allow sensory and motor neurons to communicate

Short dendrites and short axons.

Motor Neuron

Control muscle movements and glands by releasing neurotransmitters which bind to receptors on the target organ and trigger a response

Short dendrites and long axons.

Dendrites

carry impulses from neighbouring neurons to the cell body

Cell body (soma)

contains a nucleus containing genetic material.

Axons

carry impulses away from the cell body.

Myelin Sheath

Fatty layer covering the axon, protecting it and speeding up an electrical transmission impulse.

Nodes of Ranvier

speed up transmission by forcing it to 'jump' across gaps along the axon

Terminal buttons/axon terminals

the ends of axons which transmit messages to other cells via use of neurotransmitters at synapses

Receptor cells

A cell in the nervous system responsible for detecting a stimulus

Presynaptic neuron

transmits the signal toward a synapse

Postsynaptic neuron

transmits the signal away from the synapse

Vescicles

where neurotransmitters are stored before being released across nerve synapses

Neurotransmitters

Chemical messengers released from a synaptic vesicle into the synapse in order to carry an impulse from one nerve cell to another

Action Potential

the change in electric potential that propagates along the axon of a neuron during the transmission of a nerve impulse or the contraction of a muscle

Enzyme

a protein that acts as a biological catalyst

Receptor sites

Sites which take up neurotransmitters after they cross the synapse

Reuptake/reabsorption channels

Where the neurotransmitter is reabsorbed into the presynaptic neuron to be released again

Synapse

A small gap between 2 neurons in which neurotransmitters travel between to carry signals

Presynaptic membrance

The specialised membrane on the presynaptic neuron which is responsible for released neurotransmitters into the synapse

Chemical transmission

The release of neurotransmitters from the presynaptic neuron into the synapse via vesicles

Endocrine system

A collection of glands that produce hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep, mood etc.

Gland

An organ that secretes a substance (hormones) into the bloodstream

Hormone

Chemical messengers which bind to receptors to send signals

Pineal gland

Produces and regulates melatonin (controls sleep)

Pituitary gland

Controls the release of all other endocrine glands ('the master gland')

Thyroid gland

Produces and regulates thyroxine (control growth, metabolism and appetite)

Pancreas

Produces and regulates insulin (helps digestion and regulates blood sugar)

Adrenal gland

Produces and regulates adrenaline (prepares the body for fight or flight response)

Oestrogen

Produces and regulates oestrogen and progesterone

Testes

Produces and releases testosterone

Hypothalamus

Links the nervous system to the endocrine system via the pituitary gland

ACTH

Stimulates the adrenal cortex to produce cortisol (during the stress response)

Fight or Flight

Automatic physiological response which occurs during stressful situations to aid survival

Rest and digest

Follows the fight or flight response and aims to return to body to its normal state

Stressor

A stimulus that causes a stress response

Acute stress

Short-term stress that typically results from immediate stressors or challenging situations

Chronic stress

Long-term stress which impacts the functioning of an individual's everyday life

Sympathomedullary pathway

The route to which the brain directs the sympathetic branch of the autonomic nervous system to activate in response to short-term stress

Homeostasis

State of balance between all physical systems when the body is functioning 'normally'

Amygdala

Primary processor of memories and emotions associated with fear

Tend and befriend

A primarily female response to stress in which the individual tends to young and creates social connections

Beta bias

Theories that ignore or minimise sex differences

Deterministic

Belief that all events or behaviours are determined by pre-existing causes or conditions

Post mortem

Studying the physical brain of a person who displayed a particular behaviour while they were alive that suggested possible brain damage

FMRI

measures the small changes in blood flow that occur with brain activity

EEG

a recording of brain activity in which small sensors are attached to the scalp to pick up the electrical signals produced by the brain

ERP

The electrophysiological response of the brain to a specific sensory, cognitive or motor event can be isolated through statistical analysis of EEG data

PET

uses a radioactive substance called a tracer to look for disease or injury in the brain

Spatial resolution

the smallest feature (or measurement) that a scanner can detect

Temporal resolution

the accuracy of the scanner in relation of time: or how quickly the scanner can detect changes in brain activity