Biological Form is Sufficient to Create a Biological Motion Sex Aftereffect.

In a series of five experiments we sought to determine what causes the biological motion sex aftereffect-adaptation of a general representation of the stimulus sex, adaptation to the motion in the stimulus, or adaptation to the form in the stimulus. The experiments showed that (a) adaptation to gendered faces and gendered full body images did not create a biological motion sex aftereffect; (b) adaptation to moving partial biological motion displays containing the most important motion cues for sex discrimination (shoulders and hips or shoulders, hips, and feet) did not create a biological motion sex aftereffect; and (c) adaptation to a static frame or shapes derived from a static frame did create a biological motion sex aftereffect. These results suggest that form information is sufficient to create a biological motion sex aftereffect and suggests that biological motion sex aftereffects may be a result of lower level rather than higher level adaptation in the visual system.

Neural Estimates of Imagined Outcomes in Basolateral Amygdala Depend on Orbitofrontal Cortex.

Reciprocal connections between the orbitofrontal cortex (OFC) and the basolateral nucleus of the amygdala (BLA) provide a critical circuit for guiding normal behavior when information about expected outcomes is required. Recently, we reported that outcome signaling by OFC neurons is also necessary for learning in the face of unexpected outcomes during a Pavlovian over-expectation task. Key to learning in this task is the ability to build on prior learning to infer or estimate an amount of reward never previously received. OFC was critical to this process. Notably, in parallel work, we found that BLA was not necessary for learning in this setting. This suggested a dissociation in which the BLA might be critical for acquiring information about the outcomes but not for subsequently using it to make novel predictions. Here we evaluated this hypothesis by recording single-unit activity from BLA in rats during the same Pavlovian over-expectation task used previously. We found that spiking activity recorded in BLA in control rats did reflect novel outcome estimates derived from the integration of prior learning, however consistent with a model in which this process occurs in the OFC, these correlates were entirely abolished by ipsilateral OFC lesions. These data indicate that this information about these novel predictions is represented in the BLA, supported via direct or indirect input from the OFC, even though it does not appear to be necessary for learning. SIGNIFICANCE STATEMENT: The basolateral nucleus of the amygdala (BLA) and the orbitofrontal cortex (OFC) are involved in behavior that depends on knowledge of impending outcomes. Recently, we found that only the OFC was necessary for using such information for learning in a Pavlovian over-expectation task. The current experiment was designed to search for neural correlates of this process in the BLA and, if present, to ask whether they would still be dependent on OFC input. We found that although spiking activity in BLA in control rats did reflect the novel outcome estimates underlying learning, these correlates were entirely abolished by OFC lesions.

Orbitofrontal cortex supports behavior and learning using inferred but not cached values.

Computational and learning theory models propose that behavioral control reflects value that is both cached (computed and stored during previous experience) and inferred (estimated on the fly on the basis of knowledge of the causal structure of the environment). The latter is thought to depend on the orbitofrontal cortex. Yet some accounts propose that the orbitofrontal cortex contributes to behavior by signaling "economic" value, regardless of the associative basis of the information. We found that the orbitofrontal cortex is critical for both value-based behavior and learning when value must be inferred but not when a cached value is sufficient. The orbitofrontal cortex is thus fundamental for accessing model-based representations of the environment to compute value rather than for signaling value per se.

The Thatcher effect in biological motion.

We demonstrate the Thatcher effect in biological-motion displays and show that it is primarily a result of the moving, and not static, cues in the display.