PSYCH SAC 1 Flashcards
BRAIN
an intricate network of cells that plays a vital role in processing information
received through neural pathways from the body and in directing actions within
the body
3 main functions of nervous system
recieve, process and coordinate a response to information
central nervous system
brain, spinal cord: controls internal environment to maintain homeostasis, programs spinal reflexes, memory and learning, voluntary control of movement
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 subdivisions) responsible for sending messages to the body and muscles from the CNS
autonomic nervous system (PNS)
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
somatic nervous system (PNS)
a sub-division of the peripheral nervous system that carries sensory
information to the central nervous system and motor information from it. they also carry commands from your brain to your muscles so you can move around
sympathetic nervous system (ANS)
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; compare with parasympathetic nervous system
parasympathetic nervous system (ANS)
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; compare with sympathetic nervous system
concious response
a reaction to a sensory stimulus that involves awareness; usually voluntary, goaldirected and with some degree of control over it; compare with unconscious response
unconcious response
a reaction to a sensory stimulus that does not involve awareness; involuntary, unintentional, automatic and we cannot ordinarily control its occurrence; compare with conscious
response
efferent information
conducted or conducting outwards or away from something (EXITING)
afferent information
conducting or conducted inwards or towards something (ARRIVING)
synapse
small pocket of space between two cells, where they can pass messages to communicate.
synaptic gap
the tiny space between the axon terminal of a presynaptic neuron and the dendrite of a postsynaptic neuron; also called synaptic cleft
axon terminal
the button-like endings of axons through which axons make synaptic contacts with other nerve cells or with effector cells. at the axon terminal, synaptic vesicles containing neurotransmitters are docked.
pre-synaptic neuron
transmits the signal toward a synapse
post-synaptic neuron
adds together, or integrates, all of the excitatory and inhibitory inputs it receives and “decides” whether to fire an action potential
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. regulates gastric acid secretion, changes in local blood flow, interacts with the immune system in the gut.
organs in the enteric nervous system
esophagus, stomach, intestines, pancreas, rectum
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
seretonin syndrome
an excessive amount of serotonin may cause serotonin syndrome, which can be life threatening in some people. Serotonin syndrome is a collection of symptoms that includes fever, elevated heart rate, restlessness, agitation, confusion, hallucinations, delirium and seizures.
seretonin
a neurotransmitter or neuromodulator with multiple functions depending on where it acts; functions include emotional processing, mood, and sleep onset
spinal reflex
an unconscious, involuntary response to certain stimuli, initiated within the spinal cord and controlled solely by neural circuits; also called reflex arc
gamma-amino butryic acid (GABA)
the primary inhibitory neurotransmitter in the central nervous system, making postsynaptic neurons less likely to fire. helps regulate postsynaptic neurons from getting out of control and causing seizures.
glutamate
the main excitatory neurotransmitter in the CNS, thereby enhancing information transmission by making postsynaptic neurons more likely to fire
excitatory vs inhibitory effect
a neurotransmitter stimulates or activates a postsynaptic neuron to perform its functions vs 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
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
neuromodulator
a neurotransmitter that can influence the effects of other neurotransmitters; also called modulator neurotransmitter e.g dopamine, seritonin
neurotransmitter
a chemical substance produced by a neuron that carries a message to other neurons or cells in muscles, glands or other tissue. transmission of information between neurons involves
both electrical and chemical processes.
long-term depression
the long-lasting decrease in the strength of synaptic connections and
transmission and neuronal response; compare with long-term potentiation
long-term potentiation
the long-lasting enhancement of synaptic transmission due to repeated strong stimulation; compare with long-term depression
pruning
the elimination of weak, ineffective or unused synapses (and therefore connections to other neurons); also called synaptic pruning
sprouting
the creation of new extensions on a neuron to allow it to make new connections with 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
synaptic plasticity
the ability of a synapse to change in response to experience: usually as a result of learning and memory
lock & key process
each type of neurotransmitter has a chemically distinct shape. when released by the presynaptic neuron, the neurotransmitter searches for the correctly shaped receptor site on the dendrites of the postsynaptic neuron’s receptor sites.
Hebb’s Rule
When the synaptic connection between neurons is strengthened, this makes them more likely to fire together again and to transmit their signals more forcibly in the future. Hebb’s rhyme “neurons that fire together, wire together.”
brain plasticity
the ability to reorganise and relocate neural pathways based on new experiences.
adaptive plasticity
where the brain functions can be relocated to other areas of the brain to compensate for the loss of function sustained usually as a result of damage.
developmental plasticity
the process of strengthening new and frequently activated neural connections through experience with the environment and eliminating weak connections.
stress
a state of physiological and psychological arousal produced by internal or external stressors that are perceived by the individual as challenging or exceeding their ability or resources to cope
stressor
an event or circumstance that causes stress; these can be physical or psychological (noise, light, bullying etc) they activate the SYMPATHETIC nervous system
acute stress
very high level of arousal level for a relatively short time
chronic stress
involves ongoing demands pressures and worries that are long lasting. produces increased arousal level over a long period of time that is likely to be harmful to our health and wellbeing.
fight-or-flight response
is an innate and evolutionary phenomenon critical to our survival. it is an adaptive response activated by the sympathetic nervous system
fight-flight psychical changes
- increased heart rate and blood pressure
- increased breathing rate
- increased glucose (sugar) secretion by the liver
- dilation of pupils
- suppression of functions that are not immediately essential (digestion, sex drive etc)
- redistribution of bloody supply from skin and intestines to the muscles
freeze psychical changes
-body movements and vocalisations stop
- the racing heart slows significantly
- blood pressure drops rapidly
- tense muscles collapse and become still
- rest and relaxtion is dominant as part of the parasympathetic nervous system
effect of cortisol
to energise the body by increasing energy supplies such as blood sugar and enhancing metabolism, anti-inflammatory effect, prevents tissue repair
cortisol
the primary stress hormone, involved in both acute and chronic stress.
potential harm caused by long term cortisol release
- vulnerability to colds and flu
- impaired immune system functions
- high blood pressure
- high blood sugar level
- digestive problems
- heart disease vulnerability
