Thursday, December 20, 2018

Our findings support a view in which retronasal, but not orthonasal, odors share processing circuitry commonly associated with taste; this happens also in rats, which was disputed

Retronasal Odor Perception Requires Taste Cortex, but Orthonasal Does Not. Meredith L. Blankenship, Maria Grigorov, Donald B. Katz, Joost X. Maier. Current Biology, https://doi.org/10.1016/j.cub.2018.11.011

Highlights
•    Retronasal, but not orthonasal, odors facilitate rapid preference learning
•    Preferences for retronasal odors are not expressed orthonasally
•    Retronasal odors potentiate the formation of orthonasal preferences
•    Inactivating taste cortex selectively impairs expression of retronasal preferences

Summary: Smells can arise from a source external to the body and stimulate the olfactory epithelium upon inhalation through the nares (orthonasal olfaction). Alternatively, smells may arise from inside the mouth during consumption, stimulating the epithelium upon exhalation (retronasal olfaction). Both ortho- and retronasal olfaction produce highly salient percepts, but the two percepts have very different behavioral implications. Here, we use optogenetic manipulation in the context of a flavor preference learning paradigm to investigate differences in the neural circuits that process information in these two submodalities of olfaction. Our findings support a view in which retronasal, but not orthonasal, odors share processing circuitry commonly associated with taste. First, our behavioral results reveal that retronasal odors induce rapid preference learning and have a potentiating effect on orthonasal preference learning. Second, we demonstrate that inactivation of the insular gustatory cortex selectively impairs expression of retronasal preferences. Thus, orally sourced (retronasal) olfactory input is processed by a brain region responsible for taste processing, whereas externally sourced (orthonasal) olfactory input is not.

People may intuitively believe that exchanging ever-more information will foster better-informed opinions & perspectives—but much of this information may be lost on minds long made up

People use less information than they think to make up their minds. Nadav Klein and Ed O’Brien. Proceedings of the National Academy of Sciences, https://doi.org/10.1073/pnas.1805327115

Significance: People readily categorize things as good or bad, a welcome adaptation that enables action and reduces information overload. The present research reveals an unforeseen consequence: People do not fully appreciate this immediacy of judgment, instead assuming that they and others will consider more information before forming conclusions than they and others actually do. This discrepancy in perceived versus actual information use reveals a general psychological bias that bears particular relevance in today’s information age. Presumably, one hopes that easy access to abundant information fosters uniformly more-informed opinions and perspectives. The present research suggests mere access is not enough: Even after paying costs to acquire and share ever-more information, people then stop short and do not incorporate it into their judgments.

Abstract: A world where information is abundant promises unprecedented opportunities for information exchange. Seven studies suggest these opportunities work better in theory than in practice: People fail to anticipate how quickly minds change, believing that they and others will evaluate more evidence before making up their minds than they and others actually do. From evaluating peers, marriage prospects, and political candidates to evaluating novel foods, goods, and services, people consume far less information than expected before deeming things good or bad. Accordingly, people acquire and share too much information in impression-formation contexts: People overvalue long-term trials, overpay for decision aids, and overwork to impress others, neglecting the speed at which conclusions will form. In today’s information age, people may intuitively believe that exchanging ever-more information will foster better-informed opinions and perspectives—but much of this information may be lost on minds long made up.

Keywords: tipping point, change, self-insight, judgment, information processing

Do movements contribute to sense of body ownership? Rubber hand illusion in expert pianists

Do movements contribute to sense of body ownership? Rubber hand illusion in expert pianists. Maria Pyasik, Adriana Salatino, Lorenzo Pia. Psychological Research, https://link.springer.com/article/10.1007/s00426-018-1137-x

Abstract: Currently, it is still debated whether, how and to what extent movements contribute to the sense of body ownership (i.e., the feeling that one’s body belongs to oneself). To answer this question, here we examined if a prolonged increase of the amount of movements affects body ownership. Specifically, we administered the rubber hand illusion paradigm within a natural condition of long-term motor practice, namely in expert pianists. We compared the illusory effects of both static (visuotactile stimulation) and dynamic (active/passive movements) versions of that paradigm in a group of expert pianists and a group of non-musicians. The illusion was measured behaviorally (proprioceptive drift) and subjectively (questionnaire). Our results showed that pianists were significantly less susceptible to any type of the illusion, compared to the non-musicians. Moreover, they did not experience the illusion in general (presenting neither the proprioceptive drift, nor the subjective feeling of ownership). These findings suggest that the increased amount of motor-related afferent and efferent signals does affect the construction and the coherence of body ownership, thus showing the role of movements in this process.

Those with larger late positive potentials in response to food‐related cues than to erotic images are more susceptible to cue‐induced eating, eat more than twice as much than those with the opposite bran reaction

The reality of “food porn”: Larger brain responses to food‐related cues than to erotic images predict cue‐induced eating. Francesco Versace et al. Psychiohysiology, https://doi.org/10.1111/psyp.13309

Abstract: While some individuals can defy the lure of temptation, many others find appetizing food irresistible. The goal of this study was to investigate the neuropsychological mechanisms that increase individuals’ vulnerability to cue‐induced eating. Using ERPs, a direct measure of brain activity, we showed that individuals with larger late positive potentials in response to food‐related cues than to erotic images are more susceptible to cue‐induced eating and, in the presence of a palatable food option, eat more than twice as much as individuals with the opposite brain reactivity profile. By highlighting the presence of individual brain reactivity profiles associated with susceptibility to cue‐induced eating, these findings contribute to the understanding of the neurobiological basis of vulnerability to obesity.

School Bullying: Perpetrators and victims had relatively stable trajectories with most of the children remaining in the same role over time or becoming uninvolved

A Longitudinal Study on Stability and Transitions Among Bullying Roles. Izabela Zych et al. Child Development, https://doi.org/10.1111/cdev.13195

Abstract: Trajectories of stability and change in bullying roles were examined through a longitudinal prospective study of 916 school students followed up biannually from age 11 to 17. Perpetrators and victims had relatively stable trajectories with most of the children remaining in the same role over time or becoming uninvolved. Bully/victim was the most unstable role with frequent transitions to perpetrators or victims. Developmental change in bullying roles was found with a decrease in physical forms over time in bullies and victims but with persistently high perpetration and victimization in bully/victims. These findings open new horizons in research and practice related to bullying and can be useful for its early detection or design of targeted interventions.