Term
What are the 3 major Monoamine Neurotransmitter Pathways?
Origin:
Involved Structures:
Relevant Disorders: |
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Definition
Serotonin, NE and DA
1) Serotonin
O: Dorsal Raphe
IS: Cortex/Thalamus/Midbrain/BG/Cerebellum
RD: Depression and Anxiety
2) NE
O: Locus ceruleus
IS: Limbic system (amygdala, hypothalamus)/Cortex/Thalamus
RD: Depression and Anxiety
3) Dopamine
O: Ventral Tegmental Area (VTA)
IS: Substantia nigra to striatum/ Tubuloinfidubular (pituitary)/ Midbrain to limbic/cortex/ Nucleus Accumbens
RD: Schizophrenia and Addiction |
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Term
| What is the origin, involved structures and relevant disorders of the Serotonin system? |
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Definition
1) Origin in Dorsal Raphe
2) Involves Cortex, Thalamus, Midbrain, BG and Cerebellum
3) Anxiety and Depression |
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Term
| What is the origin, involved structures and relevant disorders of the Norepinephrine system? |
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Definition
1) Origins in Locus Cerulius
2) Involves Limbic system (amygdala and hypothalamus), cortex and thalamus
3) Anxiety and Depression |
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Term
| What is the origin, involved structures and relevant disorders of the Dopamine system? |
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Definition
1) Origins in the VTA
2) Involves
-Tubulo-infidubular (pituitary)
- Substantia nigra to striatum
- Midbrain to limbic/cortex
- Nucleus Accumbens
3) Schizophrenia and Addiction |
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Term
| How does DA signaling relate to positive and negative symptoms seen in Schizophrenia? |
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Definition
1) Positive symptoms involve too much DA through mesolimbic path
** Every antipsychotic that treats positive symptoms does so through inhibition of post-synatpic D2 receptors**
2) Negative symptoms involve too little DA through mesocortical pathways
The 2 pathways regulate each other (i.e. if VTA DA is high, it will be lowered in frontal cortex) through mesocortical "brake system." |
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Term
| How does glutamate signaling influence dopaminergic pathways in the context of Schizophrenia? |
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Definition
Check and Balance
1) Glutamate projections exert tonic excitatory influence on mesolimbic DA activity in VTA (polysynaptic)
2) Other projections exert NMDA-mediated stimulation of VTA GABAergic interneurons or striatotegmental GABA neurons in context of stress (or heightened DA signaling), inhibiting DA signaling
3) Mesocortical DA projections regulate this glutamatergic "brake system" |
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Term
| What are the 8 major structures of the Limbic System influencing emotional cognition? |
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Definition
3-5 layers per structure (allocortex)
1) Hippocampus
2) Amygdala
3) Cingulate
4) Parahippocampus
5) Entorhinal cortex
6) Insular cortex
7) Septal nuclei
8) Nucleus accumbens |
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Term
| What is the neural basis of Physiological, Behavioral and Psychological neurofunctional domains of emotion? |
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Definition
1) Physiological including Autonomic/Endocrine regulation of thirst, appetite and sex (HYPOTHALAMUS)
2) Behavioral including Motor/Facial regulation of fight, flee, frown (CORTEX/BASAL GANGLIA)
3) Psychological including Feeling subjective reactions (CORTEX) |
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Term
| What is the basic Functional Anatomy of the Amygdala? |
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Definition
Basal Ganglia nucleus with Limbic function (Emotional Significance of events) and found in forebrain anterior to hippocampus
INPUTS
1) Sensory Afferents (low/quick and dirty, "preconscious")
- world...thalamus...amygdala
2) Visceral Afferents (high)
- world...thalamus...cortex...amygdala
**Arrive at lateral nucleus of amygdala and then travel to Central nucleus**
OUTPUTS (dorsal-stria terminalis and ventral- amygdalofugal)
1) SNS (autonomic arousal)
2) Locus Ceruleus (NE tone, hypertension, tachycardia and behavioral fear response)
3) Paraventricular nucleus of hypothalamus (Adrenocorticoid release) |
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Term
| How do SSRIs and CBT work to treat Panic Disorder? |
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Definition
Panic Disorder is deficit in coordination of information coming to and from the amygdala (central to response to conditioned fear).
1) SSRIs decrease amygdala activity and interfere with outputs to hypothalamus and brainstem
2) CBT works upstream, "de-conditioning" contextual fear at hippocampal level, and decreasing cognitive distortions by strengthening MPFC-mediated inhibition of Amygdala |
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Term
| What are the major inputs/outputs to the structure that is found in the medial temporal lobe, and is important for integrating information by forming new declarative memories? |
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Definition
Hippocampus
1) Inputs
- Temporal cortex
- Entorhinal cortex (ERC)
2) Outputs
- Fornix
- Amygdala
- Cortex |
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Term
| What are the major inputs/outputs to the limbic structure that is found above the corpus callosum within the medial frontal lobes, and is important for modulating cognitive, responses to pain, motor responses to emotion and visuospatial processing? |
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Definition
Cingulate (Anterior= Cognitive, Pain response and Motor response to emotion. Posterior= Visuospatial)
1) INPUTS
- Frontal Lobe
- Thalamus (Anterior nuclei)
2) OUTPUTS
- Cingulum
- Parahippocampus |
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Term
| What major pathological conditions are associated with hippocampal disfunction? |
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Definition
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Term
| What major pathological conditions are associated with Cingulate gyrus dysfunction? |
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Definition
1) OCD (increased)
2) Schizophrenia
3) Bipolar D/O |
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Term
| What pathological conditions are associated with Hypothalamic dysfunction? |
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Definition
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Term
| What are the major inputs/outputs to the diencephalic structure that is found straddling the 3rd ventricle, and is important for Homeostasis and Neuroendocrine regulation? |
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Definition
Hypothalamus
1) INPUTS
- Amygdala
- Hippocampus
- BG
2) OUTPUTS
- Pituitary
- Thalamus |
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Term
| What are the major inputs/outputs to the temporal lobe structure involved in reward processing? |
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Definition
N. accumbens (Disorders of Addiction!)
1) INPUTS
- Brainstem
- Midbrain/VTA
2) OUTPUTS
- Frontal Cortex
- Limbic system |
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Term
| What is the functional anatomy of the HPA axis? |
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Definition
1) Hypothalamus releases CRH to Anterior pituitary
2) Anterior Pituitary releases ACTH to Adrenal Cortex, which releases Cortisol
**Adrenal medulla releases catecholamines**
3) Cortisol inhibits Anterior Pituitary and Hypothalamus (feedback) |
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Term
| What are the "2 neural systems" for emotion in the context of Mood disorders? |
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Definition
Cognitive-affective dysregulation arises from diminished prefrontal modulation of subcortical/limbic circuitry
1) Emotional stimulus is received by visual cortex, filtered by thalamus and interacting with the amgydala and other structures
2) Early appraisal and regulation comes from ventral anterior cingulate (ACG) and OFC
3) Reappraisal and regulation takes place later after VLPFC , DLPFC and hippocampal structures re-evalutate the stimulus |
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Term
| What is the neurobiological basis for the reduced responsiveness to happy faces that is seen in Unipolar Depression? |
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Definition
Top-down regulation issue
Unipolar depression involves reduced subcortical activity to positive emotional stimuli regulated by left orbio-mediial PFC ("top-down") |
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Term
| What is the neurobiological basis for the increased responsiveness to both positive and negative stimuli that is seen in the context of Bipolar disorder? |
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Definition
OFPFC-Amygdala issue (connected by Uncinate Fasciulus is disturbed)
Abnormally increased subocritcal activity to positive and negative emotional stimuli because of left/right OFC-amygdala "disconnectivity" |
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Term
| What is the "Alexander" loop of OCD? |
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Definition
Lateral OFC loop important for internally-guided behavior towards a reward, habit formation and stereotyped behavior.
OFC.(ant. cingulate)..Caudate...GP/Snpr....Thalamus...OFC
**Anterior Cingulate "way station" can be used in DBS to resolve symptoms** |
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Term
| How does PTSD relate to the stress response and the HPA axis? |
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Definition
Chronic stress in PTSD "sensitizes" glucocorticoid receptors to negative feedback (i.e. these receptors are found in hypothalamus and anterior pituitary).
Remember, HPA
1) Hypothalamus (CRH)
2) Anterior Pituitary (ACTH)
3) Adrenal Cortex (Corticosteroids) |
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Term
| What is an "endophenotype"? |
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Definition
| In a psychiatric illness, when the neurobiological basis is not completely known, "endophenotypes," or biological markers specific to that disorder, can help diagnosticians come close. |
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Term
The function of the amygdala is to help the organism:
a. Understand the emotional significant of events
b. Consolidate memory
c. Maintain homeostasis
d. Pay attention |
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Definition
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Term
Which limbic system structure functions abnormally in OCD?
a. Cingulate
b. Nucleus Accumbens
c. Hippocampus
D. Entorhinal cortex |
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Definition
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Term
Studies have shown that patients with chronic stress or post-traumatic stress may experience atrophy of the hippocampus. What functional outcomes are most likely sequelae of this pathophysiologic process?
a. Hyperarousal
b. Dissociation
c. Re-experiencing
d. Avoidance |
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Definition
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Term
Which NT is most closely linked with reward and reinforcement?
a. DA
b. 5-HT
c. ACh
d. All of the above? |
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Definition
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Term
Which of the following statements about emotions is TRUE?
a. Emotional valence is mediated by brainstem structures like the cerebellum
b. Generally speaking, human beings need to minimize the expression of emotion: there's no such thing as "too little" emotion
c. Emotions help us most as a guide to decision-making behavior
d. All of the above are true |
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Definition
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Term
Which part of the cortex serves to inhibit automatic emotional responses?
a. Frontal
b. Occipital
c. Parietal
d. Temporal |
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Definition
A
Remember, OFC/cingulate...caudate...Gpi/SNpr...Thalamus...OFC loop |
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