3/4 PSYCHOLOGY DEFINITIONS

Central nervous system

Comprised of the brain and spinal cord. It receives sensory information from the peripheral nervous system and sends motor information to the peripheral nervous system.

Brain

Regulates and guides all other parts of the nervous system including vital body functions (breathing, heart rate) and high order functioning (emotions)

Spinal cord

A cable like column of nerve fibres that extends from the base of the brain to the lower back. SAME: Sensory Afferent Motor Efferent

Peripheral nervous system

Comprised of muscles, organs and glands. It sends sensory information to the central nervous system and receives motor information from the central nervous system

Somatic nervous system

Transmits information from receptor sites to the central nervous system and then carries information to the muscles to initiate voluntary movement

Autonomic nervous system

Carries information between the central nervous system and the organs and glands to ensure they are regulated without conscious awareness (sympathetic and parasympathetic)

Sympathetic nervous system

Prepares the body for vigorous activity and action to deal with a potential threat by activating the fight-flight-freeze response through a release of adrenaline

Parasympathetic nervous system

maintains the body’s state of homeostasis, retuning the body to a state of calm following vigorous activity or stress/heightened arousal

Neuron

A cell within the nervous system that transmits messages to and from the brain with various functions

Sensory neurons (afferent neurons)

Transmit sensory information via afferent pathways from your body to your brain

Motor neurons (efferent neurons)

Transmit motor information via efferent pathways from the brain to the body

Interneurons

Transmits information and signals between sensory and motor neurons

Conscious response

deliberate and voluntary actions that are intentionally initiated by the brain and performed by the body involving the somatic nervous system

Unconscious response

automatic and involuntary actions that are performed without conscious awareness, typically involving the autonomic nervous system.

The spinal reflex

Occurs in response to pain and aids survival through a faster reaction time. The message is intercepted by the interneurons in the spinal cord.

Neurotransmission

A process of communication between neurons using electrochemical energy

Neurotransmitter

The chemical substance received by the terminal button of a neuron, necessary for neural communication

Excitatory

Increasing the likelihood that the neuron will fire an action potential eg. glutamate

Inhibitory

Decreasing the likelihood that a neuron will fire an action potential

Neuromodulator

A chemical messenger that enhances signal transmission

Neuroplasticity

The ability of the brain to physically change in response to experience or activity

Synaptic plasticity

The ability of synaptic connections to change over time in response or activity or experience. Includes Sprouting, rerouting and pruning

Long-term potentiation (LTP)

The Long lasting and experience-dependant strengthening of synaptic connections that are regularly activated. The increase in synaptic strength through high frequency stimulation of the neural pathways.

Long-term depression (LTD)

The long lasting and experience-dependant weakening of synaptic connections between neurons that are not regularly activated.

Stress

a psychological and physiological experience/tension that occurs when an individual encounters something of significance that demand their attention and/or efforts to cope

Distress

Characterised by a negative psychological state when a stressor presents an individual with an undesirable circumstance that appears to only lead to a negative outcome. For example: loosing car keys.

Eustress

Characterised by a positive psychological state including feeling inspired or motivated. For example: having butterflies before going on a date.

Acute stress

Characterised by intense psychological and physiological symptoms that are brief in duration (flight, fight or freeze response)

Chronic stress

A form of stress that endures for several months of longer

Stressor

A stimulus that prompts a stress response

Internal stressor

A stimulus from within a person’s body that prompts the stress response. For example: hunger, illness, low self esteem

External/environmental stressor

A stimulus from outside of a person’s body that prompts the stress response. For example: upcoming exam, financial difficulties, relationsihp conflicts

Cortisol

A hormone released in times of stress to aid the body in initiating and maintaining heightened arousal