Neural functional organization of hallucinations in schizophrenia: Multisensory dissolution of pathological emergence in consciousness

Although complex hallucinations are extremely vivid, painful symptoms in schizophrenia, little is known about the underlying mechanisms of multisensory integration in such a phenomenon. We investigated the neural basis of these altered states of consciousness in a patient with schizophrenia, by combining state of the art neuroscientific exploratory methods like functional MRI, diffusion tensor imaging, cortical thickness analysis, electrical source reconstruction and trans-cranial magnetic stimulation. The results shed light on the functional architecture of the hallucinatory processes, in which unimodal information from different modalities is strongly functionally connected to higher-order integrative areas.     

Counter-stereotypic beliefs in math do not protect school girls from stereotype threat

The threat of being negatively stereotyped in math impairs performance of highly qualified females on difficult math tests, a phenomenon known as “stereotype threat”—ST. Perhaps more alarmingly, recent studies based on unselective samples of elementary-, middle-, and high-school students show that ST also operates in girls from the general population. Here we offer first evidence that ST does operate (with large effect sizes) even in middle-school girls who deny the negative gender stereotype. Children’s beliefs about the two genders math ability, therefore, do not necessarily moderate their susceptibility to ST, an important issue that remained unclear so far. This new finding is also of great practical significance: School girls’ counter-stereotypic beliefs cannot be taken as sufficient evidence for deciding whether the struggle against ST is or is not needed. Appropriate interventions should be the default option when aiming for true gender equality in math and science achievements.     

Temporal context affects the perceived time of visual events

We investigated whether the moment at which an event is perceived depends on its temporal context. Participants learned a mapping between time and space by watching the hand of a clock rotating a full revolution in a fixed duration. Then the hand was removed, and a target disc was flashed within a fixed-interval duration. Participants were to indicate where the hand would have been at the time of the target. In three separate experiments, we estimated the disruption from a distractor disc that was presented before or after the target disc, with a variable time between them. The target was either revealed at the end of the trial or cued beforehand, and in the latter case, was cued by either color or temporal order. We found an attraction to the presentation time of the distractor when both events were attended equally (target revealed at the end). When the target was cued beforehand, the reported time was under- or overestimated, depending on whether the nature of distractor had to be decoded (precued by color) or not (precued by order). In summary, the perceived time of an event is always affected by other events in temporal proximity, but the nature of this effect depends on how each event is attended.

     

Geometry Versus Drawing: Changing the Meaning of the Task as a Means to Change Performance

There is now much convincing evidence that the context in which children are given cognitive tasks can have a huge effect on their performance in those tasks, even when the experimental and control conditions make exactly the same logical and cognitive demands. According to this, we found that children faced with a cognitive-perceptual task (the Rey–Osterrieth's complex figure reproduction test) performed better or worse in one context (geometry) than in another (drawing), depending on their performance history in these contexts, although the task was the same in both conditions. These effects are discussed both in relation to underlying processes and in perspective with another phenomenon (stereotype threat) which also provides evidence for the social regulation of cognitive functioning in the school environment. This revised version was published online in August 2006 with corrections to the Cover Date.     

Wherein Lies the Normative Dimension in Meaning and Mental Content?

Philosophical Studies -     

Looking and touching: what extant approaches reveal about the structure of early word knowledge

The goal of the current study is to assess the temporal dynamics of vision and action to evaluate the underlying word representations that guide infants' responses. Sixteen‐month‐old infants participated in a two‐alternative forced‐choice word–picture matching task. We conducted a moment‐by‐moment analysis of looking and reaching behaviors as they occurred in tandem to assess the speed with which a prompted word was processed (visual reaction time) as a function of the type of haptic response: Target, Distractor, or No Touch. Visual reaction times (visual RTs) were significantly slower during No Touches compared to Distractor and Target Touches, which were statistically indistinguishable. The finding that visual RTs were significantly faster during Distractor Touches compared to No Touches suggests that incorrect and absent haptic responses appear to index distinct knowledge states: incorrect responses are associated with partial knowledge whereas absent responses appear to reflect a true failure to map lexical items to their target referents. Further, we found that those children who were faster at processing words were also those children who exhibited better haptic performance. This research provides a methodological clarification on knowledge measured by the visual and haptic modalities and new evidence for a continuum of word knowledge in the second year of life.     

Polarity correspondence in comparative number magnitude judgments

When asked which of two digits is greater, participants respond more quickly if physical size corresponds to number magnitude, such as in 3 7, than when the two attributes contradict each other, such as in 3 7. This size congruence effect in comparative number judgments is a well-documented phenomenon. We extended existing findings by showing that this effect does not depend on physical size of the number alone but can be observed with number symmetry. In addition, we observed that symmetric numbers are judged as being smaller than asymmetric numbers, which renders an interpretation of the number symmetry congruence effect in terms of physical size implausible. We refer to the polarity correspondence principle (Proctor & Cho, 2006) to explain the present findings.