Responsiveness to terrestrial optic flow in infancy: does locomotor experience play a role?

Human infants show a peak in postural compensation to optic flow at approximately nine months of age. The current experiment tested whether the magnitude of visual-postural coupling in 9-month-olds increases when terrestrial optic flow is added to a moving room. A secondary objective was to explore whether locomotor experience plays any role in enhancing responsiveness to the additional terrestrial information. Ninety-one infants (experienced creepers, nascent creepers, and prelocomotors) were exposed to two conditions of optic flow: global optic flow (G) and global optic flow minus terrestrial optic flow (G-T). The additional terrestrial optic flow led to significantly higher visual-postural coupling. Consistent with previous findings, locomotor experience had no effect on responsiveness to the G-T condition, though there was weak evidence that the nascent creepers were more strongly influenced by the difference between flow conditions than the other infants. Unexpectedly, the prelocomotor females showed significantly lower visual-postural coupling than the prelocomotor males. These findings support the notion that the ground provides an important source of information for the control of posture and locomotion. The findings also suggest that locomotor experience most likely helps to functionalize smaller (partial), rather than larger (global), optic flow fields for postural control.     

Scalar properties in animal timing: conformity and violations

The article reviews data from animal subjects on a range of timing tasks (including fixed-interval and temporal differentiation schedules, stimulus timing, aversive conditioning, and Pavlovian methods) with respect to conformity to the two scalar properties of timing behaviour: mean accuracy and scalar (Weberian) variance. Systematic deviations were found in data from temporal differentiation schedules, timing of very short (<100 ms) or very long (>100 s) durations, effects of "task difficulty", and some special cases where circadian and interval timing seemed to interact, or where some specific durations seemed to be timed more precisely than others. Theoretical reconciliation of some of these deviations with underlying scalar timing can be achieved, but a number of problematical cases remain unexplained.     

What is the nature of the mind's pattern-recognition process?

If we look at the human mind as a pattern-recognition device, what is the nature of its pattern-recognizing? And how does it differ from the majority of pattern-recognition methods we have collectively devised over the decades? These broad philosophical questions emerge from the studies of chess thought, and we propose that a major task of the mind is to engage in “experience recognition” (Linhares & Freitas, 2010). One of the basic tenets of that proposal is that pattern recognition, in cognitive science and related disciplines, does not accurately reflect human psychology. As an example, the well-known article by Chase and Simon, “perception in chess”, and the benchmark cognitive computational models of chess, by Gobet et al. were criticized. Lane and Gobet (2011) provide serious skepticism concerning some of those arguments, and here we take the opportunity to respond and expand the theoretical constructs of “experience recognition”. We postulate that the mind's pattern-recognizing process holds the following properties: it is a highly path-dependent process; it prioritizes internal encodings; it is a self-organizing process in constant change; and it constructs its future information-processing pathways by continuously recognizing the possibilities that lie within the adjacent possible.     

Nestling barn owls assess short-term variation in the amount of vocally competing siblings

Assessing the amount of rivals is crucial to optimally adjust investment into a contest. If laboratory animals show numerical abilities, little is known about the ecological implications particularly in young animals. The two to nine barn owl (Tyto alba) siblings vocally compete for priority of access to food resources before parents actually deliver them. In dyads, the individual that vocalizes at the highest rate in the absence of parents deters its siblings from competing for next delivered prey. We tested the novel hypothesis that to optimally adjust vocal investment, barn owl nestlings assess how many of their siblings are currently competing. To singleton owlets, we broadcasted a fixed global number of calls emitted by one, two or four pre-recorded unfamiliar nestlings. We could thus distinguish the independent effect on singletons’ vocal behavior of the global number of calls produced by a brood from the number of competitors that produced these calls. Overall, nestlings retreated more from vocal contest when facing more competitors. However, in front of one highly motivated competitor, nestlings refrained from vocalizing to a larger extent than when competing against more but less motivated individuals. Therefore, young animals assess variation in the number of currently competing siblings based on individual-specific vocal cues.     

Why Are We Certain that We Exist?

Descartes was certain that he was thinking and he was accordingly certain that he existed. Like Descartes, we seem to be more certain of our thoughts and our existence than of anything else. What is less clear is the reason why we are thus certain. Philosophers throughout history have provided different interpretations of the cogito, disagreeing both on the kind of thoughts it characterizes and on the reasons for its cogency. According to what we may call the empiricist interpretation of the cogito, I can only claim to be certain of having experiences, and this certainty, as well as that of my own existence, stems from their phenomenal and subjective character. According to rationalist interpretations, on the other hand, I am certain of having some self‐reflexive propositional attitudes, and this certainty derives from their rational features. Psychiatric patients suffering from acute forms of depersonalization or of the Cotard syndrome often doubt that they think and exist, and might even believe that they don't. I argue that their study allows us to favor the empiricist interpretation of the cogito.     

The Work of Words: Poetry,Language and the Dawn of Community

Topoi - This essay explores the ontological movement of poetry, its language and words, by establishing a dialogue with the thought of three Japanese thinkers, Ki no Tsurayuki, Motoori Norinaga and...     

Brain potentials to emotional pictures are modulated by alexithymia during emotion regulation

Alexithymia is a personality trait associated with the reduced ability to regulate, identify, and communicate feelings or emotions and is often linked to psychosomatic disorders. The present study used event-related potentials (ERPs) to investigate the relationship between individual differences in alexithymia and emotion regulation. Participants classified as scoring either high or low on the revised form of the Toronto Alexithymia Scale (TAS-20; Taylor, Bagby, & Parker Psychother Psychosom 57:34–41, 1992) were asked to view negative and neutral images, adopting three different regulation strategies (expressive suppression, cognitive reappraisal, and attend) while ERPs were recorded. Results revealed an inverse relationship between TAS scores and emotion-related ERP activity during suppression, but not during reappraisal or a control “attend” condition. These results were observed in both early and late ERP latencies. These findings are interpreted according to potential differences between high- and low-TAS individuals regarding the frequency of prior utilization of suppression-based regulation strategies.     

Interaction between the DRD4 VNTR polymorphism and proximal and distal environments in alcohol dependence during emerging and young adulthood

The manifestation of alcohol dependence at different developmental stages may be associated with different genetic and environmental factors. Taking a developmental approach, we characterized interaction between the dopamine receptor 4 variable number tandem repeat (DRD4 VNTR) polymorphism and developmentally specific environmental factors (childhood adversity, college/Greek organization involvement, and delayed adult role transition) on alcohol dependence during emerging and young adulthood. Prospective data were obtained from a cohort of 234 White individuals (56% women, 44% men) who were followed up at ages 18 through 34. A longitudinal hierarchical factor model was estimated to model a traitlike persistent alcohol dependence factor throughout emerging and young adulthood and 2 residual statelike alcohol dependence factors limited to emerging adulthood and young adulthood, respectively. We accounted for those alcohol dependence factors by modeling 3 two-way interaction effects between the DRD4 VNTR polymorphism and the 3 developmentally specific environment factors. Carriers of the DRD4 long allele showed greater susceptibility to environmental effects; they showed more persistent symptoms of alcohol dependence as childhood adversity increased and more alcohol dependence symptoms limited to emerging adulthood as college/Greek organization involvement increased. Alcohol dependence among noncarriers of the long allele, however, did not differ as a function of those environments. Although replication is necessary, these findings highlight the importance of repeated phenotypic assessments across development and modeling both distal and proximal environments and their interaction with genetic susceptibility at specific developmental stages.