Reciprocity of support in coatis (Nasua nasua)

Primate sociality has received much attention and its complexity has been viewed as a driving force for the evolution of cognitive abilities. Improved analytic techniques have allowed primate researchers to reveal intricate social networks based on the exchange of cooperative acts and services. Although nonprimates are known to show similar behavior (e.g., cooperative hunting, food sharing, coalitions) there seems a consensus that social life is less complex than in primates. Here the authors present the first group-level analysis of reciprocity of social interactions in a social carnivore, the ring-tailed coati (Nasua nasua). The authors found that support in aggressive conflicts is a common feature in coatis and that this behavior is reciprocally exchanged in a manner seemingly as complex as in primates. Given that reciprocity correlations persisted after controlling for the effect of spatial association and subunit membership, some level of scorekeeping may be involved. Further studies will be needed to confirm our findings and understand the mechanisms underlying such reciprocity, but our results contribute to the body of work that has begun to challenge primate supremacy in social complexity and cognition.     

Improving neglect by TMS

Hemispatial neglect refers to the defective ability of patients to explore or act upon the side of space contralateral to the lesion and to attend to stimuli presented in that portion of space. Evidence from animal models suggests that many of the behavioural sequelae associated with visual neglect may result not solely from the size of the lesion, but also from a pathological state of increased inhibition exerted on the damaged hemisphere by the contralesional hemisphere. On the basis of these potential mechanisms underlying neglect, in this review we discuss therapeutic approaches, focusing particularly on recent research using transcranial magnetic stimulation (TMS). This technique, besides representing an ideal tool to investigate visuo-spatial attentive mechanisms in humans, has shown promising beneficial effects that might have an impact on clinical practice.     

Bodily self and schizophrenia: The loss of implicit self-body knowledge

Schizophrenia spectrum has been associated with a disruption of the basic sense of self, which pertains, among others, the representation of one's own body. We investigated the impact of either implicit or explicit access to the representation of one's own body-effectors on bodily self-awareness, in first-episode schizophrenia (FES) patients and healthy controls (HCs). We contrasted their performance in an implicit self-recognition task (visual matching) and in an explicit self/other discrimination task. Both tasks employed participant's own and others' body-effectors. Concerning the implicit task, HCs were more accurate with their own than with others' body-effectors, whereas patients did not show such self-advantage. Regarding the explicit task, both groups did not exhibit a self-advantage, and patients showed a higher percentage of self-misattribution errors. Neither self/other nor implicit/explicit effects were found in both groups when processing inanimate-objects. We propose that FES patients suffer of a disturbed implicit sense of bodily self.     

How does cognition evolve? Phylogenetic comparative psychology

Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly skillful at adapting methodologies to test multiple species. Meanwhile, evolutionary biologists have generated quantitative approaches to investigate the phylogenetic distribution and function of phenotypic traits, including cognition. In particular, phylogenetic methods can quantitatively (1) test whether specific cognitive abilities are correlated with life history (e.g., lifespan), morphology (e.g., brain size), or socio-ecological variables (e.g., social system), (2) measure how strongly phylogenetic relatedness predicts the distribution of cognitive skills across species, and (3) estimate the ancestral state of a given cognitive trait using measures of cognitive performance from extant species. Phylogenetic methods can also be used to guide the selection of species comparisons that offer the strongest tests of a priori predictions of cognitive evolutionary hypotheses (i.e., phylogenetic targeting). Here, we explain how an integration of comparative psychology and evolutionary biology will answer a host of questions regarding the phylogenetic distribution and history of cognitive traits, as well as the evolutionary processes that drove their evolution.     

Space coding for sensorimotor transformations can emerge through unsupervised learning

The posterior parietal cortex (PPC) is fundamental for sensorimotor transformations because it combines multiple sensory inputs and posture signals into different spatial reference frames that drive motor programming. Here, we present a computational model mimicking the sensorimotor transformations occurring in the PPC. A recurrent neural network with one layer of hidden neurons (restricted Boltzmann machine) learned a stochastic generative model of the sensory data without supervision. After the unsupervised learning phase, the activity of the hidden neurons was used to compute a motor program (a population code on a bidimensional map) through a simple linear projection and delta rule learning. The average motor error, calculated as the difference between the expected and the computed output, was less than 3°. Importantly, analyses of the hidden neurons revealed gain-modulated visual receptive fields, thereby showing that space coding for sensorimotor transformations similar to that observed in the PPC can emerge through unsupervised learning. These results suggest that gain modulation is an efficient coding strategy to integrate visual and postural information toward the generation of motor commands.     

Heidegger and the contradiction of Being: a dialetheic interpretation of the late Heidegger

ABSTRACT

It is well known that, from the beginning to the end of his philosophical trajectory, Martin Heidegger tries to develop a fundamental ontology which aims at answering the so-called question of Being: what does Being mean? Unfortunately, in trying to answer this question, Heidegger faces a predicament: given his own premises, speaking about Being leads to a contradiction. Moreover, according to the majority, if not all, of the interpreters who admit the existence of such a predicament, Heidegger tries to avoid the contradiction in question. But is this the only way Heidegger tries to solve the predicament? In this paper, I argue that, in some of his late works and, in particular, in the Contributions to Philosophy, Heidegger also takes into serious consideration the possibility of accepting the contradiction he faces in speaking about Being as true. If this is correct, Heidegger endorses what nowadays analytic philosophers call dialetheism, namely the metaphysical position according to which some (but not all) contradictions are true.     

Lexicality and Stimulus Length Effects in Italian Dyslexics: Role of the Overadditivity Effect

The effect of lexicality and stimulus length was studied in 32 third- and fourth-grade Italian dyslexics and in 86 age-matched controls. A visual lexical decision task was used. As proposed by Faust et al. (1999) Faust, M. E., Balota, D. A., Spieler, D. H. and Ferraro, F. R. 1999. Individual differences in information-processing rate and amount: Implications for group differences in response latency. Psychological Bulletin, 125: 777–799. [INFOTRIEVE][CROSSREF][CSA][Crossref], [PubMed], [Web of Science ®] , [Google Scholar], the results were analyzed in terms of raw reaction time (RT) data and using the z-score transformation to control for the presence of overadditivity effects. In terms of RTs, dyslexics showed a larger difference between words and nonwords (lexicality effect) and between short and long stimuli (length effect) than proficient readers. When data were transformed into z scores, only the group by length interaction remained significant while that with lexicality vanished. This pattern indicates that stimulus length has a specific role in Italian dyslexics’ reading deficit; in contrast, slowness in responding to nonwords was not specific but was interpreted as one aspect of dyslexics’ general inability to deal with alphabetical material (overadditivity effect).