Neurophysiology of Emotion DSA Flashcards
What is the role of the limbic system?
- control emotional behavior
- control motivational drives
What is the key player in the limbic system and what does it do?
Hypothalamus
- emotional experience
- physiological response
Function of the olfactory area
-olfaction and emotion strongly linked
Function of thalamus
- anterior nucleus = part of Papez circuit (formation of memories and learning)
- other regions involved in both input and output of limbic system
Part of basal ganglia involved in emotion
- nucleus accumbens
- putamen
Function of hippocampus in limbic system
- another part of papez circuit
- memory and emotion linked
- parahippocampal regions linked to surprise
Function of amygdala
-association with emotion, particularly fear and anger
Function of cingulate cortex
- mostly paleocortex (3 layers)
- some parts have full 6 layers
- many of these neurons show after discharge, which is the continuation of firing even after the event has finished
Emotions hardwired in human brains
Happy, Sad, FADS
- happiness (pleasure)
- sadness
- fear
- anger
- disgust
- surprise
What is one of the most important findings in identifying the physiological basis of emotion?
THE CIRCUITS THAT ALLOW US TO EXPERIENCE AN EMOTION ARE THE SAME CIRCUITS THAT ALLOW US TO IDENTIFY THAT EMOTION IN OTHERS
What are the 2 kinds of fear?
1) Innate (unconditioned) - fear that requires no experience (important in animals for survival, often linked to smell)
2) Learned (conditioned) - learned from first hand experience or from indirect experience
What is the role of the amygdala in fear?
- processing and recognizing social cues relating to fear
- emotional conditioning in response to fear
- memory
How does sensory input used to create fear arrive to the amygdala?
1) direct thalamoamygdaloid pathway to the lateral nucleus of the amygdala (rapid response)
2) indirect thalamocorticoamygdaloid pathway to lateral nucleus of the amygdala (later responses)
Indirect pathway goes to cortex first, which makes it a later response
What is the function of the lateral nucleus of the amygdala in learned fear?
integrates the input
I.e. pairing of sound and an electrical shock
Where is the paired information of learned fear from the lateral nucleus of the amygdala then sent?
basal and intercalated nuclei for additional processing
Where does the information of learned fear from the basal and intercalated nuclei then go?
central nucleus of the amygdala (final event) which then decides what responses are required and relays information appropriately
What is the role of the hypothalamus in fear?
generating physiological response
What happens in an individual who has damaged their amygdala?
- fear is not perceived
- conditioning related to fear does not occur
Where is anger mediated?
amygdala
What does the perception of anger require?
dopamine acting at D2 receptors
What areas of brain inhibit anger?
-neocortex
-ventromedial
-hypothalamic nuclei
-septal nuclei
(they don’t suppress the feeling of anger, but they determine if it is appropriate to act on it)
What is avoidance designed to do?
- opposite of pleasure/reward pathways
- prevent occurrence of a behavior that has short term rewards, but long term consequences
What are the anatomical substrates involved in avoidance?
- lateral posterior hypothalamus
- dorsal midbrain
- entorhinal cortex
What are the anatomical substrates involved in sadness?
- lower sector of the anterior cingulate cortex
- strongly activated when recalling sad events
