Final 8 (Neuroscience of Stress) Flashcards
Psychological and physiological response to a stimulus (stressor) that alters the body’s equilibrium
Stress
What is the difference between stress and anxiety?
Stress is caused by an external trigger, anxiety is defined by persistent excessive worry that doesn’t go away even in the absence of a stimulus/stressor
Explain the inverted U curve associated with level of stress (arousal and performance)
Performance can be impaired if arousal is too high but arousal can also support performance.
Difficult tasks are performed better during low stress levels.
Easy tasks are performed better during moderately high stress levels.
There are two responses associated within the overall stress response, what are they?
- Immediate response
- Slightly delayed response
Explain the immediate stress response
Sympathetic-adreno-medullar axis (SAM axis)
Primarily synaptic
Explain the slightly delayed stress response
Hypothalamic-pituitary-adrenal axis
Primarily hormonal
The immediate stress response is primarily hormonal, true or false?
False, it is primarily synaptic
The ____________ activates the immediate stress response
amygdala
The amygdala activates the stress response, sending distress signals to the ________________.
hypothalamus
The amygdala activates the stress response, sending distress signals to the hypothalamus. The ________________ activates the sympathetic nervous system resulting in epinephrine and norepinephrine release.
locus coeruleus
How is the HPA axis activated?
Hypothalamus releases corticotropin-releasing hormone (CRH).
Pituitary gland releases adrenocorticotropic hormone (ACTH).
Adrenal cortex releases cortisol.
The HPA axis is heavily connected to other parts of the brain, what are they?
- Prefrontal cortex
- Hippocampus
- Amygdala
Which three regions of the brain can regulate the HPA axis?
- Prefrontal cortex
- Hippocampus
- Amygdala
Physiological processes that allow the body to achieve stability despite environmental change and challenge
Allostasis (homeostasis)
Allostasis is coordinated by the…
HPA axis
Explain the HPA axis-negative feedback loop
- Cortisol produced in the adrenal cortex inhibits the hypothalamus (CRH) and pituitary glands (ACTH)
With chronic stress, the brain loses its ability to turn off the HPA axis, how does this occur?
- Abundance of cortisol and other neurotransmitters
- Chronic activation of the HPA axis can lead to cortisol resistance
Stress activates the sympathetic nervous system (SAM) and HPA axis, release of cortisol and catecholamines (dopamine, epinephrine, and norepinephrine) results in a physiological response, explain
Increased heart rate and blood pressure, and faster, shallower breathing, increased availability of glucose
Physical and psychological stressors are processed in the same brain circuits, true or false?
False, they are processed in overlapping but different brain circuits
Physical stressors predominantly activate…
Autonomic stress responses (SAM axis) for a faster response
Psychological stressors primarily activate…
The HPA axis (slower response)
When alert and control, the _____________ is in charge. During acute stress, high levels of norepinephrine and dopamine switch the control from the ___________ to the _________________.
Prefrontal cortex
Prefrontal cortex to the limbic system
An extreme state where stress responses are repeatedly activated and coping is inadequate
Allostatic overload
Chronic stress can affect learning and memory through the hippocampus and prefrontal cortex, how does this occur?
Reduced dendritic complexity
