Flashcards in Limbic System Deck (76):
What is emotion?
Subjective feelings and associated physiological states
What are subjective feelings?
explicit conscious awareness, such as fear, anxiety,
Are physiologic states of emotion implicit or explicit?
What are the two components of the physiologic part of emotion?
Skeletal muscle activity
What are the two characteristics of the limbic system that make it ideal for regulating emotions?
Connects cortex and lower parts of the brain
What are the affective responses of the limbic system?
True or false: the limbic system plays no role in memory
False--critical for certain types of memory
What is the role of the limbic system in homeostasis? (4)
What are the main components of the limbic system?
What are the two nuclei of the thalamus that are a part of the limbic system?
What are the three parts of the limbic cortex?
-Anterior cingulate gyrus
-Orbitofrontal, medial prefrontal cortex
What is the primary output of the limbic system?
What is the higher part of the brain that the amygdala is connected to?
What is the role of the hypothalamus in the limbic system?
governs and monitors internal homeostasis and
basic needs such as hunger and thirst.
Higher order limbic nuclei (e.g. amygdala, hippocampus), do what?
some awareness of external reality and begin to form memories.
What is the role of the limbic cortex?
more efficiently, effectively, and safely satisfy
limbic needs and impulses; associated with the conscious, rational
True or false: Under certain circumstances, emotions can hijack the logical mind,
and the limbic system can overturn the neocortex
What part of the brain utilizes dopamine?
What are the parts of the mesolimbic system?
NAcc, mPFC, septal nuclei
What neurotransmitter does the Locus ceruleus use?
What neurotransmitter does the raphe nuclei use?
What neurotransmitter do the nucleus basalis and septal nuclei use?
True or false: the hypothalamus is fully functional at birth
How is the hypothalamus involved in the emotional response?
Through the ANS
What are the two way the hypothalamus send information?
The hypothalamus can mediate body responses between internal and external information. What is the part of the brain that is necessary for conscious appreciation of stimuli, and emotional response?
What is the role of the amygdala?
Integrative center for emotions, emotional behavior, and
What are the three groups of nuclei in the amygdala?
1. Corticomedial nucleus
2. Basolateral nucleus
3. Central nucleus
What are the major inputs into the amygdala? (4)
What are the two outputs of the basolateral nucleus of the amygdala?
What are the major input/outputs of the central nucleus of the amygdala (they're all reciprocal)?
What is the major input into the corticomedial nucleus of the amygdala?
What is the output of the olfactory nucleus of the amygdala?
To the hypothalamus, then to pituitary
What are the three major outputs of the amygdala?
Why is the basolateral part of the amygdala enlarged in humans?
Major input area that projects to the central nucleus of the amygdala
What part of the brain is involved in recognition of facial expression?
What is the role in homeostasis that the amygdala plays? (2)
Conditioning of autonomic responses
What is the effect of an amydalectomy?
Flat affect, loss of fear
What is the role of the amygdala in memory and learning?
-Response to aversive stimuli
-Modulate working memory
What part of the brain works with the amygdala to play a role in motivation and emotion?
What is the underlying neural circuit in learning of the amygdala?
Synaptic connections of sensory inputs to
amygdala neurons are strengthened
How does the activity of the amygdala change when presented with faces?
Stimulation of the amygdala produces what?
A sense of familiarity
What is the role of the amygdala in homeostasis?
The somatosensory cortex projects to what nucleus in the amygdala in the neural circuit of fear conditioning? Where does this send projections to?
Basolateral -- to the PVN, LH and CG of the hypothalamus
What is the role of the PVN (paraventricular nucleus) of the hypothalamus in the neural circuit of fear conditioning pathway?
What is the role of the lateral hypothalamus in the neural circuit of fear conditioning pathway?
What is the role of the auditory cortex in the neural circuit of fear conditioning?
Projects to the basolateral nucleus of the amygdala.
What are the three types of conditional fear in humans?
What is instructed fear?
Telling someone you will hurt them
What is observational fear?
CS after the subject observed someone else undergoing fear conditioning
What does the hippocampus do in learning and memory?
What is the role of the medial prefrontal cortex in fear?
Regulates how much fear the amygdala expresses
Why do teenagers suck?
No cortex to regulate amygdala
What part of the brain deals with the raw and reflexive emotional response to stimuli?
What part of the brain deals with the external emotional feature of reality/assign emotional significance to what is experienced?
What part of the brain is involved in understanding emotions of others?
Mirror neurons of the limbic cortex
What are mirror neurons?
Neurons that activate the same neural pathways just by seeing someone else do it
What part of the brain mediate empathy?
Only that part of the pain network associated
with its affective qualities, but not its sensory qualities, mediates empathy.
A lesion where will produce the following symptoms:
• Poor judgment
• Depressive behaviors
What are the three areas of the brain that are involved in the brain reward system?
Ventral tegmental area
What is the major neurotransmitter involved in the reward pathway
What composes the nucleus accumbens?
Caudate nucleus + putamen (= striatum)
What is the underlying circuitry of the brain reward system?
What is the reward signal?
Dopamine from ventral tegmental area (VTA) to nucleus accumbens
What are the inputs into the nucleus accumbens in the reward pathway? (4)
Where does the nucleus accumbens output to in the reward pathway?
Ventral Pallidus to thalamus
What is the gist of the reward pathway?
AND BACK TO CORTEX!
What other loop is similar to the reward loop?
motor loop and goal directed behavior
What part of the thalamus is involved in the limbic loop?
What is the function of the VTA in the reward system?
What is the role of the limbic system in the reward system?
emotional processing in the limbic
system can signal the presence of rewards and can promote the activation of
motor programs to acquire the beneficial rewards
What is the MOA of addicting drugs such as cocaine, heroin, opiates, marijuana etc?
act on elements of the limbic circuitry by
altering the neuromodulatory influence of dopamine
What is the effect of addictive substances on the reward pathway?
Addiction dampens the response of reward circuitry to natural rewards, and
intensifies the response to addictive drugs, resulting in “hypofrontality” –
reduced cortical control of emotional behaviors.
What is the effect of addiction on the frontal lobe?
Reduced goal setting
Lack of motivation