SAC #1 U3 Annotated Folio

central nervous system

The major function of the Central NS is to process information received from the body's internal and external environment and to activate an appropriate response. It consists of the brain & the spinal cord.

the brain

The brain integrates the information that it receives from the environment and coordinates the activity of all parts of the body.

spinal cord

The major functions are to transmit sensory information from the peripheral NS to the brain, to transmit motor impulses from the brain to the peripheral NS and to provide a rapid spinal reflex for protection

Distinguish afferent vs efferent messages

Afferent messages carry sensory information from the peripheral ns to the central ns, for processing. Efferent messages carry motor information from the central ns to the peripheral ns to produce a response.

peripheral nervous system

it carries information to the central nervous system from sensory receptors, organs and glands. It also carries information from the central nervous system to the body's effectors.

autonomic nervous system

it regulates and modifies the activity of visceral muscles, which controls the activity of internal organs and glands. it unconsciously provides and responds to feedback from the brain

somatic nervous system

the motor function is that efferent messages are carried by motor neurons to skeletal muscles enabling voluntary movement. the sensory function is that afferent messages are detected by the sensory organs and then conveyed to the Central NS where it will be processed.

sympathetic nervous system

it prepares the body for action in a stressful situation, by increasing physiological arousal and providing the body with a burst of energy, via activation of the Fight-Flight-Freeze response

parasympathetic nervous system

it restores the body to a state of calm, by reversing the physiological changes, once the need for activity of the sympathetic NS has passed. it keeps the bodily systems functioning efficiently by maintaining homeostasis during low stress times.

detection and removal of a splinter in the toe

The sensory receptors in the skin, which is part of the peripheral NS detects the splinter in the toe. Sensory neurons carry afferent signals to the brain via the spinal cord in the central NS. The interneurons in the brain will integrate the sensory and motor information and then initiate a motor response. Motor neurons convey efferent signals via the spinal cord back to the motor neurons to direct the appropriate skeletal muscles, in the somatic NS to remove the splinter from her toe.

reflex arc after putting hand close to flame

sensory receptors in the skin, which is part of the peripheral NS detect the hot flame and afferent messages are carried by the sensory neurons via afferent tracts, to the spinal cord. The interneurons in the spinal cord connect and integrate the sensory message with a motor message, thus triggering a response independent of the brain. The motor neurons convey efferent messages via the efferent tract to the appropriate skeletal muscles in the somatic NS so that her hand can withdraw from the flame. After this the sensory messages are carried to the brain where pain can be interpreted.

Neurotransmitters

electrochemical signals that carry messages across the synapse to other neurons, muscles or organs

vesicles

store neurotransmitters until an action potential is triggered

reuptake channels

collects excess neurotransmitters to be reused

axon terminal of presynaptic neuron

stores neurotransmitters in vesicles and then sends them into the synapse

dendrite of postsynaptic neuron

receives electrochemical stimulation from other neurons

receptor

binds to specific matching chemically shaped neurotransmitters

Describe the lock and key process for neural transmission

The neurotransmitter is the key and it binds with and opens the complimentary lock, which must be a precisely matching receptor with an identical shape and size, to open the ion channels and lead to an influx of positive or negative ions, which may or may not cause the postsynaptic neuron to fire.

how neurotransmitters have an excitatory effect of postsynaptic neuron

soma initiates an action potential and neurotransmitter are released into the synapse. once a neurotransmitter binds with it's precisely matching receptor it opens up an ion channel which allows sodium ions to permeate the postsynaptic neuron, leading to an influx of positively charged ions and makes it more likely to fire

how neurotransmitters have an inhibitory effect of postsynaptic neuron

soma initiates an action potential and neurotransmitter are released into the synapse. once a neurotransmitter binds with it's precisely matching receptor it opens up an ion channel and allows chloride ions to enter the channels and leads to an influx of negatively charged ions which make it less likely for the postsynaptic neuron to fire

drugs that have an agonistic effect on neurotransmitters.

Drugs that increase the effect of the neurotransmitters are agonists. they make the receptors more receptive to the neurotransmitters in the synapse and thus increase the uptake of the neurotransmitters.

Distinguish between a neurotransmitter that has an excitatory effect vs. one that has an inhibitory effect

Excitatory neurotransmitters increase the permeability of the sodium ion channels, making the postsynaptic neuron more likely to fire. Whereas inhibitory neurotransmitters cause the chloride ion channels to briefly open, which leads to an influx of negatively charged chlorine ions, thus making the postsynaptic neuron less likely to fire.

Factors affecting context-specific effectiveness

to determine the manner in which we cope with stress, they must consider situational determinants of coping effectiveness, the personal characteristics of the individual involved, and the demands of the stressor itself

Coping Flexibility

it refers to the ability to effectively modify or adjust one's coping strategies according to the demands of different stressful situations.

indicators of coping flexibility

It includes the abilities to select and apply a coping strategy that suits the situational circumstances.

Recognise when the coping strategy being used is ineffective and then discontinue it and replace with a more effective strategy

Individuals with high coping flexibility

Can monitor and determine if an existing coping strategy is effective. And then readily adjust their coping strategies if they are ineffective. They tend to use a variety of coping strategies across situations.

Individuals with low coping flexibility

They lack the ability to recognise that an existing coping strategy is ineffective and tend to rely on the same coping strategies across different situations, and persist with them, even in the face of ineffectiveness. These individuals are not very adaptable.

Benefits of exercise to cope with stress

exercise uses up stress hormones such as adrenaline and cortisol far more rapidly than rest. it releases beta-endorphins which improves mood, and reduces stress as well as pain. And exercise helps reduce muscle tension associated with high Sympathetic NS activity.

approach coping strategies

approach coping strategies involves activity that is focused towards the stressor and deals directly with it and its effects.

Avoidance coping strategies

avoidance coping strategies involve activity that is focused away from the stressor and there is no attempt to actively confront the stressor and its causes

Strengths of approach coping strategies

They are generally considered to be more adaptive and effective. People who rely more on them tend to experience fewer psychological symptoms and are more able to function effectively compared to people who rely more on avoidance strategies

Limitations of approach coping strategies

It may require a lot of the individual's energy and focus to deal with the stressor, thereby neglecting other aspects of their lives.

Strengths of avoidance coping strategies

It can be more effective in coping with stress in the short term. and allows for the conservation of energy to focus on other stressors that can be changed. Ignoring a stressor for a couple of days can provide time out from a stressor while minimising potential stress from another source.

limitations of avoidance coping strategies

Avoidant coping strategies tend to be maladaptive, and can trigger stress-related physical problems. Long-term use of avoidance strategies can also contribute to other problems such as substance use and over time, avoidances can prevent people from responding to stressors in constructive ways.

both approach and avoidance strategies used for coping.

In some situations, we may first use an avoidance strategy, which allows us to deal with the intense emotions that have been triggered by an especially overwhelming stressor. Then, later on, when we are feeling somewhat better, we can evaluate our situation and use an approach strategy to look for ways of managing the stressor or solutions.

role of dopamine agonists in Parkinson's disease

Dopamine agonists mimic the effects of dopamine by binding to the dopamine receptors, increasing its excitatory effect and thus enhancing the control of motor functions .

drugs that have an antagonistic effect on neurotransmitters.

Drugs that decrease the effect of neurotransmitters are antagonists. They make the receptors less receptive to the neurotransmitters in the synapse and thus decrease the uptake of the neurotransmitters.

role of caffeine as an antagonist

Caffeine shares a similar molecular structure to adenosine which is an inhibitory neurotransmitter, thus caffeine can act on adenosine receptors sites, acting as an antagonist by blocking the uptake of adenosine, which decreases its inhibitory effects and explains why caffeine consumed late in the day, can increase arousal and prevent sleep as it reduces the effects of adenosine in reducing arousal and promoting sleep.