Feeding Behavior Assessment
Objective: Measurement of eating behavior and food intake following muscimol microinjection in nucleus accumbens shell to test whether rostral shell muscimol produces positive motivational states while caudal shell produces negative states
Protocol Steps
Muscimol microinjection into nucleus accumbens shell
Administer muscimol microinjection into either rostral or caudal regions of the nucleus accumbens shell
Note: Rostral injections (75 ng) elicit appetitive eating; caudal injections elicit defensive treading
View evidence from paper
“Microinjection of the GABA A agonist muscimol in the rostral medial accumbens shell in rats elicits appetitive eating behavior, but in the caudal shell instead elicits fearful defensive treading behavior”
Measure eating behavior
Assess and quantify feeding behavior following muscimol microinjection
Note: Rostral shell injections cause increased eating behavior
View evidence from paper
“Farthest rostral muscimol microinjections (75 ng) caused increased eating behavior”
Measure conditioned place preference/avoidance
Conduct behavioral place preference/avoidance conditioning to assess motivational valence
Note: Rostral injections produce positive place preferences; caudal injections produce place avoidance
View evidence from paper
“we measured behavioral place preference/avoidance conditioning and affective hedonic and aversive orofacial expressions”
Measure taste-elicited orofacial expressions
Record hedonic and aversive orofacial expressions (gapes, etc.) in response to taste stimuli
Note: Rostral injections increase positive hedonic reactions to sucrose; caudal injections increase negative aversive reactions
View evidence from paper
“affective hedonic and aversive orofacial expressions of taste-elicited liking and disliking (gapes, etc.)”
Measure fear and defensive behaviors
Assess fearful defensive treading behavior and other fear-related responses
Note: Caudal shell injections elicit fearful defensive treading; rostral injections may elicit mixed positive/negative effects at intermediate sites
View evidence from paper
“caudal shell microinjections elicited negative defensive treading and caused robust negative conditioned place avoidance”