PSIO 305 EXAM 3 QUESTIONS & ANSWERS
Definition of a stressor - Answer -A physical (external), chemical (internal), or
psychological (mental) factor resulting in tension of the body or mind
Real or perceived threat to homeostasis
Definition of allostasis - Answer -Process by which the body responds to stressors in
order to maintain or regain homeostasis
Order of events and time frame for the stress responses of the body - Answer -1.
Sympathetic activation within 2-3 seconds
2. Activation of adrenal medulla in 20-30 seconds
3. HPA axis activation in minutes, hours, or days
4. Cortisol negative feedback to suppress stress response
Properties of sympathetic activation due to stress response - Answer --HR increases,
vasoconstriction and Na/water retention lead to higher BP
-glycogenolysis, gluconeogenesis and lipolysis increases nutrient availability
-Bronchodilation
-pupil dilation
-reduced digestion and bladder relaxation direct resources and attention to stressor
-increased blood flow to skeletal muscle
Properties of adrenal medulla activation due to stress - Answer --Releases epinephrine
-sympathetic activity weans quickly, epinephrine is longer lasting
Properties of HPA (hypothalamus, pituitary, adrenal gland) axis activation due to stress
- Answer --Glucocorticoids: break down proteins, fatty acids, glycogen,
gluconeogenesis, vasoconstriction, immunosuppression
-Minerolocorticoids: Na/water retention leads to increased blood volume/pressure
Area of affect for cortisol negative feedback - Answer -Cortisol acts on the
hypothalamus to prevent release of CRH
,Cortisol suppresses the immune system response (which is a stressor)
Summary of stress responses - Answer --Sympathetic -> initiator, rapid, adaptive
-Adrenal medulla release of epinephrine -> reinforcement that keeps response
going/maintains response
-HPA axis: 1. provides metabolic support for stress responses
2. ends stress response when stressor is neutralized ->terminator
3. provides metabolic support for repair and rebuilding
4. regains homeostasis
Characteristics of PTSD - Answer -1. symptoms must last more than one month to be
diagnosed as PTSD
2. Symptoms may start a period after the traumatic event
3. PTSD can be a chronic and sometimes life-long illness
Mental/psychological/behavioral symptoms of PTSD - Answer -1. intrusive memories:
recurrent, unwanted distressing memories of the traumatic event
2. Avoidance: trying to avoid thinking or talking about the traumatic event, avoiding
people/places that remind them of it
3. Cognitive and mind disorder: negative thoughts about self, other people, and the
world
4. Changes in physical and emotional reactions: being easily startled, always on guard,
self-destructive behaviors
Distinguishing characteristic of PTSD related to hormones - Answer -Hypocortisolism ->
CRH levels are elevated but cortisol levels are reduced
Hypersensitivity or anterior pituitary to cortisol -> causes low cortisol levels
Hypothalamus increases CRH release trying to boost cortisol level -> drives abnormal
stress encoding and fear processsing
Effect of hypocortisolism on the hippocampus - Answer --Hippocampus has CRH
receptors, excess CRH release causes hippocampal atrophy
-causes learning/memory impairment and anxiety
,Autoimmune disease in PTSD - Answer -Rheumatoid arthritis
Diabetes
Hypocortisolism as a risk factor for PTSD - Answer --low cortisol level before or shortly
after the traumatic event is predictive of subsequent PTSD
-high levels of cortisol associated with low incidence of PTSD
-high doses of corticosterone reduces subsequent PTSD in animal models
Genetic influences on PTSD - Answer --Monozygotic twins have significantly higher
concordance for PTSD than dizygotic twins
-estimated 30% heritability
-genes associated with HPA axis are associated with PTSD
Epigenetic influences on PTSD - Answer --previous experience (childhood trauma, or
repeated trauma) may alter the genome epigenetically, conferring PTSD susceptibility
Activation of beta2 receptors on blood vessels in muscle - Answer --causes slow and
mild vasodilation
Dexamethasone suppression test (DST) - Answer -Used to assess adrenal gland
function by measuring how cortisol levels change in response to an injection of
dexamethasone
dexamethasone -> provides negative feedback to pituitary gland to suppress secretion
of ACTH
PTSD response to DST - Answer --increased suppression of cortisol compared to
healthy individuals
31 segments of the spinal cord - Answer -1. cervical: 8
2. thoracic: 12
3. Lumbar: 5
4. Sacral: 5
5. Coccygeal: 1
-each segment has a pair of nerves
, Dorsal and Ventral roots of the spinal cord - Answer -Dorsal root -> carry afferent
sensory information
Dorsal ganglia -> contains cell bodies of somatic and visceral afferent neurons
Ventral root -> carry efferent information from the CNS to muscles and glands
Autonomic ganglion -> contains cell bodies of post-ganglionic autonomic neurons
Two types of nerve tissue - Answer -Gray matter -> unmyelinated nerve cell bodies
-clusters of cell bodies in the CNS are nuclei
-dendrites
-axon terminals
White matter -> myelinated axons
-axon bundles connecting CNS regions are tracts
-contains very few cell bodies
Connections for afferent somatic neurons and afferent visceral neurons - Answer -
Connect with interneurons in the dorsal horns
Contents of ventral and lateral horns of the spinal cord - Answer -Ventral horns ->
contains cell bodies of efferent neurons
Lateral horns -> contain cell bodies of pre-ganglionic autonomic neurons
Direction of info in the descending, ascending and propriospinal tracts - Answer -
Ascending tracts -> take sensory info to the brain
Descending tracts -> carry signals from the brain
Propriospinal tracts -> stay in the spinal cord
Spinal reflexes - Answer --Integrated in the spinal cord -> response is initiated without
input from the brain
-stimulus triggers response from sensory cell that carries info to interneuron that
synapses with the spinal cord where the info is directly relayed to effector
Connections for the different parts of the brain stem: midbrain, pons, medulla oblongata
- Answer -midbrain -> connects to forebrain
pons -> connects to cerebellum
medulla oblongata -> connects to spinal cord
Definition of a stressor - Answer -A physical (external), chemical (internal), or
psychological (mental) factor resulting in tension of the body or mind
Real or perceived threat to homeostasis
Definition of allostasis - Answer -Process by which the body responds to stressors in
order to maintain or regain homeostasis
Order of events and time frame for the stress responses of the body - Answer -1.
Sympathetic activation within 2-3 seconds
2. Activation of adrenal medulla in 20-30 seconds
3. HPA axis activation in minutes, hours, or days
4. Cortisol negative feedback to suppress stress response
Properties of sympathetic activation due to stress response - Answer --HR increases,
vasoconstriction and Na/water retention lead to higher BP
-glycogenolysis, gluconeogenesis and lipolysis increases nutrient availability
-Bronchodilation
-pupil dilation
-reduced digestion and bladder relaxation direct resources and attention to stressor
-increased blood flow to skeletal muscle
Properties of adrenal medulla activation due to stress - Answer --Releases epinephrine
-sympathetic activity weans quickly, epinephrine is longer lasting
Properties of HPA (hypothalamus, pituitary, adrenal gland) axis activation due to stress
- Answer --Glucocorticoids: break down proteins, fatty acids, glycogen,
gluconeogenesis, vasoconstriction, immunosuppression
-Minerolocorticoids: Na/water retention leads to increased blood volume/pressure
Area of affect for cortisol negative feedback - Answer -Cortisol acts on the
hypothalamus to prevent release of CRH
,Cortisol suppresses the immune system response (which is a stressor)
Summary of stress responses - Answer --Sympathetic -> initiator, rapid, adaptive
-Adrenal medulla release of epinephrine -> reinforcement that keeps response
going/maintains response
-HPA axis: 1. provides metabolic support for stress responses
2. ends stress response when stressor is neutralized ->terminator
3. provides metabolic support for repair and rebuilding
4. regains homeostasis
Characteristics of PTSD - Answer -1. symptoms must last more than one month to be
diagnosed as PTSD
2. Symptoms may start a period after the traumatic event
3. PTSD can be a chronic and sometimes life-long illness
Mental/psychological/behavioral symptoms of PTSD - Answer -1. intrusive memories:
recurrent, unwanted distressing memories of the traumatic event
2. Avoidance: trying to avoid thinking or talking about the traumatic event, avoiding
people/places that remind them of it
3. Cognitive and mind disorder: negative thoughts about self, other people, and the
world
4. Changes in physical and emotional reactions: being easily startled, always on guard,
self-destructive behaviors
Distinguishing characteristic of PTSD related to hormones - Answer -Hypocortisolism ->
CRH levels are elevated but cortisol levels are reduced
Hypersensitivity or anterior pituitary to cortisol -> causes low cortisol levels
Hypothalamus increases CRH release trying to boost cortisol level -> drives abnormal
stress encoding and fear processsing
Effect of hypocortisolism on the hippocampus - Answer --Hippocampus has CRH
receptors, excess CRH release causes hippocampal atrophy
-causes learning/memory impairment and anxiety
,Autoimmune disease in PTSD - Answer -Rheumatoid arthritis
Diabetes
Hypocortisolism as a risk factor for PTSD - Answer --low cortisol level before or shortly
after the traumatic event is predictive of subsequent PTSD
-high levels of cortisol associated with low incidence of PTSD
-high doses of corticosterone reduces subsequent PTSD in animal models
Genetic influences on PTSD - Answer --Monozygotic twins have significantly higher
concordance for PTSD than dizygotic twins
-estimated 30% heritability
-genes associated with HPA axis are associated with PTSD
Epigenetic influences on PTSD - Answer --previous experience (childhood trauma, or
repeated trauma) may alter the genome epigenetically, conferring PTSD susceptibility
Activation of beta2 receptors on blood vessels in muscle - Answer --causes slow and
mild vasodilation
Dexamethasone suppression test (DST) - Answer -Used to assess adrenal gland
function by measuring how cortisol levels change in response to an injection of
dexamethasone
dexamethasone -> provides negative feedback to pituitary gland to suppress secretion
of ACTH
PTSD response to DST - Answer --increased suppression of cortisol compared to
healthy individuals
31 segments of the spinal cord - Answer -1. cervical: 8
2. thoracic: 12
3. Lumbar: 5
4. Sacral: 5
5. Coccygeal: 1
-each segment has a pair of nerves
, Dorsal and Ventral roots of the spinal cord - Answer -Dorsal root -> carry afferent
sensory information
Dorsal ganglia -> contains cell bodies of somatic and visceral afferent neurons
Ventral root -> carry efferent information from the CNS to muscles and glands
Autonomic ganglion -> contains cell bodies of post-ganglionic autonomic neurons
Two types of nerve tissue - Answer -Gray matter -> unmyelinated nerve cell bodies
-clusters of cell bodies in the CNS are nuclei
-dendrites
-axon terminals
White matter -> myelinated axons
-axon bundles connecting CNS regions are tracts
-contains very few cell bodies
Connections for afferent somatic neurons and afferent visceral neurons - Answer -
Connect with interneurons in the dorsal horns
Contents of ventral and lateral horns of the spinal cord - Answer -Ventral horns ->
contains cell bodies of efferent neurons
Lateral horns -> contain cell bodies of pre-ganglionic autonomic neurons
Direction of info in the descending, ascending and propriospinal tracts - Answer -
Ascending tracts -> take sensory info to the brain
Descending tracts -> carry signals from the brain
Propriospinal tracts -> stay in the spinal cord
Spinal reflexes - Answer --Integrated in the spinal cord -> response is initiated without
input from the brain
-stimulus triggers response from sensory cell that carries info to interneuron that
synapses with the spinal cord where the info is directly relayed to effector
Connections for the different parts of the brain stem: midbrain, pons, medulla oblongata
- Answer -midbrain -> connects to forebrain
pons -> connects to cerebellum
medulla oblongata -> connects to spinal cord
