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Task 7 Amygdala (Human amygdala lesion --> shift task :D !! (neural…

- - - - vmPFC
        --> high activity when you should stay with choose image (task stay condition)
        --> positive feedback cause it tells you what you're doing is good
        :!!:---> signals expected reward (in task 5 says expected reward in medial OFC lol!) strength of activity in proportion to how much reward expected :p!
      - amygdala lesion
        
        --> very little activity in above areas
        
        ----> because no value update of stimulus to lOFC and vmPFC (see task 5 both for stimulus value comparison :3 !!), and no action value update to dmACC
        
        ---> indication / feedback to switch comes from amygdala, as in people where its damaged no normal / very little activity, that otherwise would be super active in response to positive/negative feedback!!! ---> amygdala = needed for task switching
        :!!:-----> fun fact actual task switch is initiated by pre-SMA (task6) after amygdala gives feedback to MCC,lOPF, vmPFC and they decide based on feedback whats the best action :3 !!
      - MCC + lOFC
        --> high activity for when you should switch task in control condition(task switching condition)
        --> negative feedback (because is telling you to change to the there picture)
    - - Punishment (negative feedback /switch :D!)
        --> lOFC (stronger than avlPFV) activity in avlPFV (anterior venture lateral PFC)
        --> signifies updating of value (cause good before now less value because wrong choice :3 !!
        ------> no difference in amygdala lesion people
        Fig 6A, right panel. Note that here punishment leads to higher activation compared to reward, in line with its response to negative feedback (as a stimulus-reward update signal) and with the "No-reward" signalling cells described for lOFC in Rolls (2016). #
      - Reward (positive feedback / stay)
        --> activity in vmPFC + mOFC (mOFC = reward expectation/choosing stimulus with highest value (input of values by lOFC))
        -----> no difference in amygdala lesion people #
      - Amygdala lesion = no effect
        ---> BUT could be due to no power cause only 2 people!!
        ---> so amygdala doesn't impair processing of punishment and reward (which makes sense cause thats like dopamine and habenula and positive/ negative feedback!!):!!:
        ---> reward = more sought after cause positive feedback (by vmPFC) = doesn't disrupt default mode network as much cause basically says 'STAY' little analysis needed, AS COMPARED TO negative feedback (dmACC + lOFC) cause brain needs to analyze why it needs to change so less default mode and more executive functioning :3!!
        
        Caution. It may be due to lack of statistical power. Moreover, the outcome of the choice (reward or punishment) is also processed by the visual-parietal-prefrontal system (the "high route" in LeDoux's model of amygdala functioning). As a consequence, patients know "rationally" the consequences of heir choice, but they have no "affective" response (via LeDoux's "low route") from the amygdala telling them how they "feel" about (or value) this outcome.
        Remember here the study by De Martino et al (2006), which shows that the amygdala signal biases "rational" decisions. In their experiment, this signal drove the participants to "unrational" decisions, whereas in the current study this signal improves performance of the control parrticipants.
- - - - monkey study:
        --> stimulus followed by either juice (positive reinforcement/ valence) or air puff (negative reinforcement / valence) (stimulus reward reversed after some time :3 !!)
        -------> separate specific groups of neurons in amygdala fires for each positive and negative reinforcement/valence (PROOFS AMYGDALA FIRES FOR POSITIvE AFFECT AS WELL!!)
      - rats:
        --> two stimuli given , only one rewarded with food, --> later both stimuli presented no food given, rats would spend more time at stimulus that previously predicted food
        -----> amygdala lesions = abolished that response though (ergo amygdala = for positive affect as well :3 !
      - humans,
        --> faces with either positive or negative info about person!
        --> amygdala active in both positive and negative info :D!
    - - Thought because damage to either OFC or amygdala, that both are involved in stimulus reward processing
        
        ----> monkeys amygdala lesions = less fear of snake, but no issue learning new stimulus reward associations (values of stimuli) which shouldn't be possible if amygdala was involved in S-R learning :3 !! #
      - Studies:
        --> object reversal tasks (values of stimuli switch :D!), animal has to adjust values :3 !! #
        --> win-stay, lose-shift task (1 trial where two stimuli presented, one with reward, one without. After 1 trial they get presented again without reward and the animal must choose the one that was previously shown with reward and avoid the other)
        
        ----> previously shown to be impaired by amygdala lesion BUT old lesioning technique that damaged more than just amygdala!!
        
        ----> newer more exact lesioning shows no impairment in these tasks (very mild impairment in win stay lose shift, and none in reversal!!)!! (so no impact on stimulus reward learning!!)
        !!!! ---> works cause visually guided rules / action chooses based on IT (inferior temporal)+ PRh (perirhinal cortex) :D!! (see below two system 2.....)
        -------> (lesion to amygdala still reduce fear expression :3 !! as such would modulate visually guided rules as well :D!!)
        :!:------> (fun fact also doesn't need Ip+ pRh cause dopa can also influence that :3!!)