Chapter 2 - Nervous System Functioning Flashcards
Brain
a complex organ
contained within the skull
that coordinates mental
processes and behaviour,
and regulates bodily
activity
Spinal Cord
a cable of
nerve tissue that extends
from the brain, connecting
it to the peripheral
nervous system
Central Nervous System
Comprised of the brain and spinal cord. Receives neural messages from and transmits neural messages to the PNS. Processes info from the internal and external environment and formulates responses to this info
Peripheral Nervous System
a major division of
the nervous system
comprising every neuron
in the body outside the
central nervous system
Somatic Nervous System
a division of the peripheral
nervous system that
transmits neural messages
related to voluntary motor
movement (subdivision of PNS)
Skeletal Muscles
muscles
connected to the skeleton
that carry out voluntary
motor movements
Autonomic Nervous System
regulates the activity of visceral muscles, organs and glands, which occurs unconsciously and involuntarily (subdivision of PNS)
Sympathetic Nervous System
activates visceral muscles, organs, and glands, preparing the body to respond to a threat or stressor. Sympathetic responses energise the body, enabling it to engage in high levels of physical activity and
confront a threatening or stressful situation. (subdivision of autonomic nervous system)
Parasympathetic Nervous System
maintains the optimal and balanced functioning
of visceral muscles, organs, and glands. This involves returning them to optimal and balanced functioning after experiencing heightened bodily arousal due to sympathetic responses, as well as maintaining homeostasis. (subdivision of autonomic nervous system)
Neuron
individual nerve cells that are specialised to receive, process and/or transmit information (communication with other neurons, organs and glands)
Motor Neurons (efferent neurons)
neurons that transmit neural messages about motor movement from the central nervous system to the peripheral
nervous system
Sensory Neurons (afferent neurons)
neurons that transmit neural messages about bodily sensations from the peripheral nervous system to the
central nervous system
Conscious response
a conscious response to a sensory stimuli is a deliberate and voluntary action that involves awareness
Unconscious response
an unconscious response to sensory stimuli are automatic and involuntary actions that occur without awareness. involves physiological responses of the autonomic nervous system, and the spinal reflex
Spinal Reflex
a spinal reflex is an unconscious, involuntary and automatically occurring response to sensory stimuli without the involvement of the brain. the immediate response at the spinal cord occurs a fraction of a second before the sensory info reaches the brain, therefore an adaptive response that does not require awareness
Dendrite
branches extensions of a neuron that contain receptor sites which receive specific neurochemicals from the pre-synaptic neuron and transmits it to the cell body
Cell body/Soma
Integrates information received from the pre-synaptic neurons and generates and action potential
Axon
Conveys the neural impulse away from the cell body towards the axon terminals
Myelin sheath
speeds up neural transmission and protects the axon
Axon Terminals
contains synaptic vesicles that hold neurochemicals. located at the end of a neuron and releases neurochemicals into the synapse
Synaptic Gap
space between pre and post synaptic neuron where neurochemicals are released into
Synapse
Includes axon terminal of pre-synaptic neuron, synaptic gap, and dendrites of post synaptic neuron
Neurochemicals
Chemical messages that transmit info within the nervous system
Pre-synaptic neuron
the neuron that releases neurochemicals into the neural synapse
Synaptic Gap
the space between the pre-synaptic neuron and post-synaptic neuron
Receptor sites
a protein molecule on the dendrites of a neuron that receives neurochemicals
Synaptic Transmission
the chemical conveyance of neural information between two neurons across a neural synapse
Neurotransmitters
a chemical molecule that has an effect on one or two postsynaptic neurons. they mass chemical messages from pre to post, released into the synaptic gap, and works moderately fast (few seconds) with shorter term effects
Action potential
an electrical impulse that travels down the axon of a neuron
Glutamate
The main excitatory neurotransmitter in the nervous system. Involves in learning and memory.
Too much = seizure
GABA
the main inhibitory neurotransmitter in the nervous system. It fine tunes neurotransmission in the brain, preventing overexcitation of neurons.
Too little = anxiety
Excitatory effect
when the neurotransmitter makes the post synaptic neurons more likely to fire an action potential
Inhibitory effect
when the neurotransmitter makes the post synaptic neurons less likely to fire an action potential
Neuromodulators
neurochemicals that are released into the neural tissue in brain regions, which alter the strength of the signal transmission and effect entire brain regions (has an effect on multiple postsynaptic neurons)
Dopamine
a neuromodulator primarily responsible for voluntary movement, the experience of pleasure, and reward-based learning and motivation. can be inhibitory of excitatory (depending on receptor sites present at the location)
Serotonin
a neuromodulator that is primarily responsible for the regulating behaviour processes such as aggression, appetite, memory. responsible for regulation of mood and sleep (circadian rhythm)
Synaptic Plasticity
The ability of synaptic connections to change over time in response to activity or experience
Sprouting
The ability of dendrites or axons to develop new extensions or branches
Rerouting
the ability of a neuron that is connected to a damaged neuron to create an alternative synaptic connection with an undamaged neuron
Pruning
the elimination of synaptic connections that are not adequately activated
Long-Term Potentiation
the long-lasting strengthening of synaptic connections between neurons, after repeated stimulation of the same neural pathways, resulting in enhanced synaptic transmission
Long-Term Depression
The long-lasting weakening in the strength of synaptic connections which reduces synaptic efficiency due to the repeated low level stimulation of the post synaptic neuron
