NEUROSC M101C Lecture Notes - Lecture 4: Flupentixol, Parabrachial Area, Incentive Salience
Document Summary
Purely homeostatic theory cannot explain food motivation. Hedonic impact = pleasure vs impact, liking", which can be measured by pleasure ratings, facial expressions, taste receptivity. Incentive motivation = wanting, motivational value of reward or stimuli that have been paired with reward. Pleasurable things (food, water, sex, social, addictive drugs) will increase nac release of da in striatal regions. Conclusions: correlation between da and performing reward-related behavior. Cannot extrapolate a cause from the data! Da is not necessarily mediating pleasure that is experienced under these circumstances. Increase nac da (by dat knockdown or amph) does not increase reward liking" - no increase of taste reactivity measures. Decrease da (by receptor blockade or lesioning da neurons) does not decrease positive hedonic reactions or increase negative hedonic reactions. Pd patients with depleted da have normal subjective pleasure ratings for sweet foods. Da release (measured by pet) induced by amph does not correlate with measures of liking.