Intuition and autism: a possible role for Von Economo neurons

Von Economo neurons (VENs) are a recently evolved cell type which may be involved in the fast intuitive assessment of complex situations. As such, they could be part of the circuitry supporting human social networks. We propose that the VENs relay an output of fronto-insular and anterior cingulate cortex to the parts of frontal and temporal cortex associated with theory-of-mind, where fast intuitions are melded with slower, deliberative judgments. The VENs emerge mainly after birth and increase in number until age 4 yrs. We propose that in autism spectrum disorders the VENs fail to develop normally, and that this failure might be partially responsible for the associated social disabilities that result from faulty intuition.     

Chimpanzee (Pan troglodytes) intentional communication is not contingent upon food

Studies of great apes have revealed that they use manual gestures and other signals to communicate about distal objects. There is also evidence that chimpanzees modify the types of communicative signals they use depending on the attentional state of a human communicative partner. The majority of previous studies have involved chimpanzees requesting food items from a human experimenter. Here, these same communicative behaviors are reported in chimpanzees requesting a tool from a human observer. In this study, captive chimpanzees were found to gesture, vocalize, and display more often when the experimenter had a tool than when she did not. It was also found that chimpanzees responded differentially based on the attentional state of a human experimenter, and when given the wrong tool persisted in their communicative efforts. Implications for the referential and intentional nature of chimpanzee communicative signaling are discussed.     

Dimensions of impulsivity and aggression associated with suicide attempts among bipolar patients: a preliminary study

Impulsivity and hostility are often thought to be interrelated among depressed patients with suicidal behavior, but few studies have examined this relationship empirically. In this study, we assessed trait impulsivity and hostility among 52 DSM-IV bipolar subjects with and without histories of suicide attempts. Impulsivity and hostility were correlated among attempters (r = .41, p = .03) but not non-attempters (r = .22, p = .28). As compared to non-attempters, attempters had significantly higher levels of overall hostility, more extensive subcomponents of hostility, and a trend toward higher overall impulsivity. Associations between lifetime suicide attempts and overall hostility were significant while controlling for current depression severity and lifetime illness duration. Aggression and impulsivity appear linked among bipolar patients with lifetime suicide attempts but may be independent constructs among non-attempters. The presence of both factors may elevate risk for suicidal behavior.     

Avoidance and depression: the construction of the cognitive-behavioral avoidance scale

Previous research has demonstrated a relationship between avoidance and depression, although the nature of this relationship has been confused by inconsistent definitions of avoidance. Following a review of the construct of avoidance and an examination of past research, a new multidimensional measure of avoidance was developed and validated using an undergraduate student sample (245 females and 146 males). Four reliable factors reflecting combinations of cognitive/behavioral and social/nonsocial dimensions of avoidance were obtained from the factor analysis of the new scale, entitled the "Cognitive-Behavioral Avoidance Scale" (CBAS). The scale showed the predicted relationships with convergent and divergent measures used for construct validation. As predicted, subscales of the CBAS, as well as the overall scale score, were significantly related to the depression and anxiety criterion measures. The findings from this study suggest that avoidance may be an important construct in the psychosocial conceptualization of depression. In addition, this integrated measure of avoidance has potential utility for depression researchers. Suggestions for further scale development and research are provided.     

You’ll see what you mean: Students encode equations based on their knowledge of arithmetic

This study investigated the roles of problem structure and strategy use in problem encoding. Fourth-grade students solved and explained a set of typical addition problems (e.g., ) and mathematical equivalence problems (e.g., or ). Next, they completed an encoding task in which they reconstructed addition and equivalence problems after viewing each for 5 s. Equivalence problems of the form overlap with a perceptual pattern found in traditional arithmetic problems (i.e., answer blank in final position), and students’ encoding was poorest on problems of this type. Individual differences in encoding the equivalence problems were related to variations in strategy use. Some students solved blank-final equivalence problems using the standard arithmetic strategy of performing all given operations on all given numbers. These students made more errors in encoding problem structure, but fewer errors in encoding the numbers, than did students who solved the problems using correct or other incorrect strategies. Moreover, students who expressed many strategies for solving the blank-final equivalence problems made fewer errors in encoding problem structure, but more errors in encoding the numbers, than did students who expressed only a single strategy. Results highlight that encoding is intended to guide action and that prior experience can simultaneously facilitate and interfere with accurate encoding.     

Increasing false recognition rates with confirmatory feedback: a phenomenological analysis

During a simulated witness interrogation, participants were encouraged to confabulate an account consistent with false information concerning a videotaped event. The interviewer verbally affirmed some false responses. Previous research has shown that, a week later, participants often recognize confabulated events that were affirmed by the experimenter as being from the video. What is unclear is whether confirmatory feedback encouraged a change in the mental representation of the confabulated events to fit the original event or confirmation might have merely encouraged a change in beliefs about the event. To further understand the mechanisms that underlie the confirmatory feedback effect, participants were asked to judge the phenomenological experience associated with false recognition.