Abstract The present study evaluated the role of inhibition in paradoxical choice in pigeons. In a paradoxical choice procedure, pigeons receive a choice between two alternatives. Choosing the “suboptimal” alternative is followed 20% of the time by one cue (the S+) that is always reinforced, and 80% of the time by another cue (S-) that is never reinforced. Thus, this alternative leads to an overall reinforcement rate of 20%. Choosing the “optimal” alternative, however, is followed by one of two cues (S3 or S4), each reinforced 50% of the time. Thus, this alternative leads to an overall reinforcement rate of 50%. González and Blaisdell (2021) reported that development of paradoxical choice was positively correlated to the development of inhibition to the S- (signal that no food will be delivered on that trial) post-choice stimulus. The current experiment tested the hypothesis that inhibition to a post-choice stimulus is causally related to suboptimal preference. Following acquisition of suboptimal preference, pigeons received two manipulations: in one condition one of the cues in the optimal alternative (S4) was extinguished and, in another condition, the S- cue was partially reinforced. When tested on the choice task afterward, both manipulations resulted in a decrement in suboptimal preference. This result is paradoxical given that both manipulations made the suboptimal alternative the richer option. We discuss the implications of our results, arguing that inhibition of a post-choice cue increases attraction to or value of that choice.
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A special role for Anterior Cingulate Cortex, but not Orbitofrontal Cortex or Basolateral Amygdala, in choices involving information
Humans and other animals make decisions under uncertainty. Choosing an option that provides information can improve decision making. However, subjects often choose information that does not increase the chances of obtaining reward. In a procedure that promotes such paradoxical choice, animals choose between two alternatives: The richer option is followed by a cue that is rewarded 50% of the time (No-info) and the leaner option is followed by one of two cues, one always rewarded (100%), and the other never rewarded, 0% (Info). Since decisions involve comparing the subjective value of options after integrating all their features perhaps including information value, preference for information may rely on cortico-amygdalar circuitry. To test this, male and female Long-Evans rats were prepared with bilateral inhibitory DREADDs in the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), basolateral amygdala (BLA), or null virus infusions as a control. Using a counterbalanced design, we inhibited these regions after stable preference was acquired and during learning of new Info and No-info cues. We found that inhibition of ACC, but not OFC or BLA, selectively destabilized choice preference in female rats without affecting latency to choose or the response rate to cues. A logistic regression fit revealed that the previous choice strongly predicted preference in control animals, but not in female rats following ACC inhibition. BLA inhibition tended to decrease the learning of new cues that signaled the Info option, but had no effect on preference. The results reveal a causal, sex-dependent role for ACC in decisions involving information.
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- Award ID(s):
- 1844144
- NSF-PAR ID:
- 10458422
- Date Published:
- Journal Name:
- bioRxiv
- ISSN:
- 2692-8205
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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