Biopsychology (definitions) Flashcards
The nervous system
A specialised network of cells which acts as our primary internal communication system
The central nervous system
The origin of all complex commands and decisions, made up of the brain and spinal chord
The peripheral nervous system
Sends information from the outside world to the CNS, and from the CNS to muscles and glands
The somatic nervous system
Controls muscle movement and receives information from sensory receptors
The autonomic nervous system
Transmits information to and from internal bodily organs, governing vital functions in the body
The endocrine system
A major information system which instructs glands to create and secrete hormones directly into the bloodstream, controlling vital functions in the body
The parasympathetic state
The autonomic nervous system’s normal resting state
The sympathetic state
The autonomic nervous system’s physiologically aroused state
Gland
An organ in the body which synthesises substances such as hormones
Hormones
Chemical substances that circulate in the bloodstream and affect target organs
Neuron
Nerve cell which processes and transmits messages through electrical and chemical signals
Sensory neurons
Neurons which carry messages from the PNS to the CNS
Relay neurons
Neurons which connect the sensory neurons to the motor neurons
Motor neurons
Neurons which carry messages from the CNS to effectors such as muscles and glands
Nucleus (soma)
Part of the neuron which contains the genetic material of the cell
Dendrites
Branch-like structures which carries nerve impulses from neighbouring neurons towards the cell body
Axon
Part of the neuron which carries impulses away from the cell body down the length of the neuron
Myelin sheath
A fatty layer which protects the axon and speeds up electrical transmission of the impulse
Nodes of Ranvier
Gaps in the myelin sheath which speed up the transmission of the electrical impulse by forcing it to jump
Terminal buttons
The end of the axon which communicates with the next neuron across the synapse
Synaptic transmission
The process by which neighbouring neurons communicate with each other by sending chemical signals across the synapse
Neurotransmitter
Brain chemicals released from synaptic vesicles that relay signals across the synapse from one neuron to another
Excitation
When a neurotransmitter increases the positive charge of the postsynaptic neuron, increasing the likelihood that the neuron will fire
Inhibition
When a neurotransmitter increases the negative charge of the postsynaptic neuron, decreasing the likelihood that the neuron will fire
Action potential
Information in the form of an electrical impulse which travels down the axon
Localisation of function
The theory that different areas of the brain are responsible for different behaviours, processes, and functions
Lateralisation
When particular functions are controlled by a particular hemisphere of the brain
Frontal lobe
The ‘motor area’ of the cortex, which sends messages to the muscles via the brain stem and spinal chord
Parietal lobe
The ‘somatosensory area’ of the cortex, where sensory information from the skin is represented
Occipital lobe
The ‘visual area’ of the cortex, which receives visual information contralaterally from the eyes
Temporal lobe
The ‘auditory area’ of the cortex, which receives auditory information contralaterally from the ears
Broca’s area
The small area in the left frontal lobe responsible for speech production
Wernicke’s area
The region in the left temporal lobe responsible for language comprehension
Holistic theory of the brain
The theory that all areas of the brain are involved in the processing of thought and action
Plasticity
The tendency of the brain to change and adapt, physically and functionally, as a result of experience and new learning
Functional recovery
Following damage, the ability of the brain to redistribute functions usually performed by a damaged area to an undamaged area
Synaptic pruning
The process of removing rarely used synaptic connections which occurs as we age
Synaptogenesis
The rapid expansion in synaptic connections which occurs as the brain experiences a bombardment of sensory input
Axonal sprouting
Following brain damage, the growth of new nerve endings which connect with undamaged nerve cells to form new neuronal pathways
Recruitment of homologous areas
Following brain damage, when the equivalent area on the opposite side of the brain to the damaged area carries out its function
Commissurotomy
Split-brain surgery in which the corpus callosum and other tissue connecting the two hemispheres of the brain is severed
fMRI
A brain scanning method which detects changes in blood oxygenation and flow to identify active regions of the brain
EEG
A measure of electrical activity in the brain via electrodes fixed to the scalp which provides an overall account of brain activity
ERP
statistical analysis of EEGs which isolates the brain’s electrophysiological response to a particular stimulus
Post-mortem examinations
Analysis of the physical brain after death to identify abnormalities which can be linked to behaviour in the individual’s life
Biological rhythm
A distinct pattern of changes in bodily activity which conforms to cyclical time periods
Endogenous pacemakers
The body’s internal biological ‘clock’ which influences biological rhythms
Exogenous zeitgebers
External changes in the environment which influence biological rhythms
Circadian rhythm
A biological rhythm which occurs once every 24 hours
Infradian rhythm
A biological rhythm which occurs less than once every 24 hours
Ultradian rhythm
A biological rhythm which occurs more than once every 24 hours
REM sleep
The sleep stage in which the body is paralysed but brain activity speeds up significantly. At this point you have fast, jerky eye movements. This phase of sleep is known to be associated with dreaming.
Developmental plasticity
The tendency of the brain to change and adapt during infancy as the brain is exposed to a vast range of experiences, environments and stimuli
Adaptive plasticity
The ability of the brain to change and adapt through functional brain recovery following trauma
Neurorehabilitation
The process of supporting people after brain trauma to regain as much function as possible
SAD
Seasonal Affective Disorder: irritability, despair, and lack of motivation triggered in winter when daylight hours are reduced
