Afferent
conducting or conducted inwards or towards something
autonomic nervous system
a subdivision of the peripheral nervous system that connects the central nervous system to the body's internal organs and glands, providing feedback to the brain about their activities
brain
an intricate network of cells that plays a vital role in processing information received through nerve pathways from the body and in directing actions within the body
central nervous system
the brain and spinal cord
conscious response
a reaction to a sensory stimulus that involves awareness; usually voluntary, goal-directed and with some degree of control over it
dopamine
a neurotransmitter or neuromodulator with multiple functions depending on where it acts; functions include roles in coordinating movement, learning and behaviours that are rewarding
enteric nervous system
a sub-division of the autonomic nervous system embedded within the walls of the gastrointestinal (digestive) tract and dedicated to its functioning
efferent
conducted or conducting outwards or away from something
excitatory effect
when a neurotransmitter stimulates or activates a postsynaptic neuron to perform its functions
ganglia
small clusters of neurons
gamma-amino butyric acid (GABA)
the primary inhibitory neurotransmitter in the central nervous system, making postsynaptic neurons less likely to fire
glutamate
the main excitatory neurotransmitter in the CNS, thereby enhancing information transmission by making postsynaptic neurons more likely to fire
inhibitory effect
when a neurotransmitter blocks or prevents a postsynaptic neuron from firing and therefore performing its functions
interneuron
a neuron which transmits impulses between other neurons, especially as part of a reflex arc
long-term depression
the long-lasting decrease in the strength of synaptic connections and transmission and neuronal response
long-term potentiation
the long-lasting enhancement of synaptic transmission due to repeated strong stimulation
motor neuron
a nerve cell forming part of a pathway along which impulses pass from the brain or spinal cord to a muscle or gland
nervous system complex
highly organised network of specialised cells that enables the brain to receive information about what is going on from both inside and outside the body and to respond appropriately
neural pathway
a route based on interconnected neurons that form a communication network within the brain and between the brain and other parts of the nervous system and body
neural synapse (also called neural junction or synapse)
the site where communication typically occurs between adjacent neurons
neuromodulator (also called modulator neurotransmitter)
a neurotransmitter that can influence the effects of other neurotransmitters
neurons
the building blocks of the brain and the rest of the nervous system
neurotransmission
the transmission of nerve impulses between neurons or between a neuron and a muscle fibre or other structure
neurotransmitter
a chemical substance produced by a neuron that carries a message to other neurons or cells in muscles, glands or other tissue
parasympathetic nervous system
a sub-division of the autonomic nervous system that calms or restores the body to its normal state of functioning after the need for sympathetic nervous system activation has passed
peripheral nervous system
entire network of nerves located outside the central nervous system; carries information to and from the central nervous system (via its somatic and autonomic sub-divisions)
pruning (also called synaptic pruning)
the elimination of weak, ineffective or unused synapses (and therefore connections to other neurons)
rerouting
when new connections are made between neurons to create alternate neural pathways
sensory stimuli
any event or object that is received by the senses and elicits a response from a person
sensory neuron
nerve cells that are activated by sensory input from the environment
sensory receptor
a nerve ending that sends signals to the. central nervous system when it is stimulated
serotonin
a neurotransmitter or neuromodulator with multiple functions depending on where it acts; functions include emotional processing, mood, and sleep onset
somatic nervous system
a sub-division of the peripheral nervous system that carries sensory information to the central nervous system and motor information from it
spinal reflex (also called reflex arc)
an unconscious, involuntary response to certain stimuli, initiated within the spinal cord and controlled solely by neural circuits
spinal cord
a long, thin bundle of nerve tissue connecting the brain and rest of the body via the peripheral nervous system; initiates simple reflex responses independently of the brain
sprouting
the creation of new extensions on a neuron to allow it to make new connections with other neurons
synaptic plasticity
the ability of a synapse to change in response to experience
synaptic gap (also called synaptic cleft)
the tiny space between the axon terminal of a presynaptic neuron and the dendrite of a postsynaptic neuron
sympathetic nervous system
a subdivision of the autonomic nervous system; activates internal muscles, organs and glands to prepare for vigorous activity or to deal with a stressor, fear stimulus, threat or emergency
unconscious response
a reaction to a sensory stimulus that does not involve awareness; involuntary, unintentional, automatic and we cannot ordinarily control its occurrence