Chapter 3 (NERVOUS SYSTEM FUNCTIONING) Flashcards
Central Nervous System (CNS)
the brain and the spinal cord;
processes and coordinates
responses to sensory stimuli
Brain
a complex structure that receives and processes
sensory stimuli from the body and coordinates
responses
Spinal Cord
a dense bundle of nerves that carries sensory information from the body to the
brain and motor information from
the brain to the body
Spinal Reflex
an involuntary and unconscious response to a stimulus involving the spinal cord, which occurs without input from the brain
Sensory Receptor
a sensory nerve ending
that produces an afferent or sensory impulse when stimulated
Sensory Neuron
a nerve cell that carries
sensory signals throughout the nervous system
Interneuron
a nerve cell in the spinal cord that connects
motor and sensory neurons by relaying
information between the two
Motor Neuron
a nerve cell that transmits motor impulses from the spinal cord to the skeletal and smooth muscles
Peripheral Nervous System (PNS)
all the nerves outside of the central nervous system that carry messages between the
central nervous system and muscles, organs and glands throughout the body
Somatic Nervous System
a subdivision of the peripheral nervous system that carries sensory information
to the central nervous system and motor information to the body
Autonomic Nervous System
a subdivision of the peripheral nervous system that controls the
body’s internal environment in
an autonomous or self-regulated manner
Sympathetic Nervous System
a subdivision of the autonomic
nervous system that increases our arousal, readying the
body for a quick response
Parasympathetic Nervous System
a subdivision of the autonomic
nervous system that controls the
body’s internal environment in
an autonomous or self-regulated
manner
Unconscious Response
any response of our nervous
system that does not require awareness
Conscious Response
any response of the nervous
system that requires awareness
Neuron
an individual nerve cell that
is specialised to receive, process
and/or transmit information
within the nervous system
Neural Transmission
an electrical impulse that occurs when a neuron is activated or fires
Neurotransmitter
a chemical produced by neurons
that carries messages to other neurons or cells within the nervous system, including muscles, organs and glands
Synapse
the point of communication between two neurons or between a neuron and a target cell such as a muscle or gland
Synaptic Vesicle
a membrane-bound sphere
filled with neurotransmitter molecules
Synaptic Gap
the space between the axon terminal of the presynaptic neuron and the membrane of the post-synaptic neuron
Receptor Site
a membrane protein on the
dendrites of neurons that receive and detect specific neurotransmitters
Excitatory Effect
the increased likelihood that the post-synaptic neuron will fire an action potential or neural impulse
Glutamate
the main excitatory neurotransmitter in the nervous
system, which is involved with
learning and memory
Inhibitory Effect
the decreased likelihood that
the post-synaptic neuron will
fire an action potential or neural impulse
GABA (Gamma-
aminobutyric
acid)
the main inhibitory neurotransmitter in the nervous
system, associated with anxiety, specific phobias and Parkinson’s
disease
Neuromodulator
a subclass of neurotransmitters
that alter the strength of neural transmission, by increasing or decreasing the responsiveness
of neurons to neurotransmitter signals
Dopamine
a multifunctional neurotransmitter with both excitatory and inhibitory effects, that is involved in many central nervous system functions such as movement, pleasure, attention, mood, cognition and motivation
Reward Pathway
a group of structures in the brain that are activated by rewarding or reinforcing stimuli
Serotonin
an inhibitory neurotransmitter
that also acts as a neuromodulator, influencing a
variety of brain activities
Synaptic Plasticity
specific changes that occur within the synapse, between neurons
Serotonin Pathway
serotonin’s neuromodulatory system, which originates in the brainstem and extends to almost all areas of the cerebrum including the cerebral cortex
LTP (Long - Term Potention)
the relatively permanent strengthening of synaptic connections as a result of repeated activation of a neural pathway
LTD (Long - Term Depression)
the relatively permanent
weakening of synaptic
connections as a result of
repeated low- level activation
Sprouting
the growth of axon or dendrite
fibres at the synapse
Dendritic Spine
a dendrite fibre that grows by
sprouting on the post-synaptic
neuron
Filigree Appendage
a fibre that grows by
sprouting from the axon terminal of the presynaptic
neuron
Synaptogenesis
the formation of new synapses
that result from the process of
sprouting
Rerouting
the formation of new connections between neurons
to establish alternative neural pathways
Pruning
the removal of excess neurons
and synaptic connections to increase the efficiency of neuronal transmissions
