Chapter 3 - Nervous system functioning

Question 1

autonomic nervous system

Answer 1

a subdivision of the peripheral nervous system that controls the body’s internal environment in an autonomous or self-regulated manner (without conscious awareness) - directly connected to organs, glands and visceral muscles - responsible for basic life processes - has a major role in the experience of stress, fear and anger

Question 2

brain

Answer 2

a complex structure that receives and processes sensory stimuli from the body and coordinates responses, including voluntary movements, emotions and conscious thought. - communicates with the body via the spinal cord and cranial nerves

Question 3

central nervous system

Answer 3

the brain and the spinal cord; processes and coordinates responses to sensory stimuli. - integrates and coordinates all incoming (sensory/afferent) information and initiates outgoing (motor/efferent) messages to be sent to the body.

Question 4

conscious response

Answer 4

any response of the nervous system that requires awareness

Question 5

cranial nerve

Answer 5

connect the brain directly to various organs and muscles of the body - considered to be a part of the peripheral nervous system

Question 6

dendritic spine

Answer 6

a dendrite fibre that grows by sprouting on the post-synaptic

Question 7

dopamine

Answer 7

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 - is a modulating neurotransmitter or neuromodulator because it reinforces the neural activity in regions of the brain associated with these functions, for example the reward pathway.

Question 8

excitatory effect

Answer 8

the increased likelihood that the post-synaptic neuron will fire an action potential or neural impulse

Question 9

filigree appendage

Answer 9

a fibre that grows by sprouting from the axon terminal of the presynaptic neuron

Question 10

gamma-aminobutyric acid (GABA)

Answer 10

the main inhibitory neurotransmitter in the nervous system, associated with anxiety, specific phobias and Parkinson’s disease

Question 11

glutamate

Answer 11

the main excitatory neurotransmitter in the nervous system, which is involved with learning and memory by stimulating essential structural and functional changes to the connections between neurons

Question 12

inhibitory effect

Answer 12

the decreased likelihood that the post-synaptic neuron will fire an action potential or neural impulse

Question 13

interneuron

Answer 13

a nerve cell in the spinal cord that connects motor and sensory neurons by relaying information between the two

Question 14

long-term depression (LTD)

Answer 14

the relatively permanent weakening of synaptic connections as a result of repeated low-level activation

Question 15

long-term potentiation (LTP)

Answer 15

the relatively permanent strengthening of synaptic connections as a result of repeated activation of a neural pathway

Question 16

motor neuron

Answer 16

a nerve cell that transmits motor impulses from the spinal cord to the skeletal and smooth muscles

Question 17

neural transmission

Answer 17

an electrical impulse that occurs when a neuron is activated or fires (aka an action potential) -> causes transmission of a signal to post-synaptic neuron - when an action potential travels down an axon and into an axon terminal, it triggers chemical changes within the terminal. -> causes the synaptic vesicles to merge with the membrane at the presynaptic terminal and release neurotransmitters into the synaptic gap

Question 18

neuromodulator

Answer 18

a subclass of neurotransmitters that alter the strength of neural transmission, by increasing or decreasing the responsiveness of neurons to neurotransmitter signals - does not result in excitation or inhibition of a specific neuron. Instead, it can alter both the cellular and synaptic properties of multiple neurons so that neurotransmission between them is altered

Question 19

neuron

Answer 19

an individual nerve cell that is specialised to receive, process and/or transmit information within the nervous system

Question 20

neurotransmitter

Answer 20

a chemical produced by neurons that carries messages to other neurons or cells within the nervous system, including muscles, organs and glands

Question 21

parasympathetic nervous system

Answer 21

a subdivision of the autonomic nervous system that controls the body’s internal environment in an autonomous or self-regulated manner - maintains homeostasis - counterbalances the sympathetic nervous system

Question 22

peripheral nervous system

Answer 22

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

Question 23

pruning

Answer 23

the removal of excess neurons and synaptic connections to increase the efficiency of neuronal transmissions

Question 24

receptor site

Answer 24

a membrane protein on the dendrites of neurons that receive and detect specific neurotransmitters

Question 25

rerouting

Answer 25

the formation of new connections between neurons to establish alternative neural pathways

Question 26

reward pathway

Answer 26

a group of structures in the brain that are activated by rewarding or reinforcing stimuli - controls our responses to natural rewards and is therefore an important determinant in motivation - When we are exposed to these rewarding stimuli, the brain increases the release of dopamine along this reward pathway in the brain, which modulates the brain activity of the structures along it. The more dopamine released within the reward centre, the more a stimulus is sensed as a reward.

Question 27

sensory neuron

Answer 27

a nerve cell that carries sensory signals throughout the nervous system

Question 28

sensory receptor

Answer 28

a sensory nerve ending that produces an afferent or sensory impulse when stimulated

Question 29

serotonin

Answer 29

an inhibitory neurotransmitter that also acts as a neuromodulator, influencing a variety of brain activities

Question 30

serotonin pathway

Answer 30

serotonin's neuromodulatory system, which originates in the brainstem and extends to almost all areas of the cerebrum including the cerebral cortex

Question 31

somatic nervous system

Answer 31

a subdivision of the peripheral nervous system that carries sensory information to the central nervous system and motor information to the body

Question 32

spinal cord

Answer 32

a dense bundle of nerves that carries sensory information from the body to the brain and motor information from the brain to the body

Question 33

spinal reflex

Answer 33

an involuntary and unconscious response to a stimulus involving the spinal cord, which occurs without input from the brain when a quick response is important for your survival.

Question 34

sprouting

Answer 34

the growth of axon or dendrite fibres at the synapse

Question 35

sympathetic nervous system

Answer 35

a subdivision of the autonomic nervous system that increases our arousal, readying the body for a quick response (FFF) - dominant in response to perceived threats and stressful psychological or physiological stimuli - pupils dilate - heart rate, blood pressure & breathing rates increase - inhibits digestion - increased sugar and fat release

Question 36

synapse

Answer 36

the point of communication between two neurons or between a neuron and a target cell such as a muscle or a gland

Question 37

synaptic gap

Answer 37

the space between the axon terminal of the presynaptic neuron and the membrane of the post-synaptic neuron

Question 38

synaptic plasticity

Answer 38

specific changes that occur within the synapse, between neurons

Question 39

synaptic vesicle

Answer 39

a membrane-bound sphere filled with neurotransmitter molecules

Question 40

synaptogenesis

Answer 40

the formation of new synapses between activated axon terminals and new dendritic spines

Question 41

unconscious response

Answer 41

any response of our nervous system that does not require awareness

Question 42

spinal reflex processes

Answer 42

1 - sensory stimulus detected by sensory receptors -> produce and afferent/sensory impulse 2 - sensory neurons transmit sensory information about the stimulus towards the spinal cord 3 - sensory information relayed to interneurons in the spinal cord -> an adaptive motor response is initiated by the interneurons without input from the brain 4 - information about this motor movement is relayed to motor neurons, which transmit the motor impulses from the spinal cord to the skeletal and/or smooth or visceral muscles 5 - muscles are activated to perform the movements required