Selective improvement of strain-dependent performances of cognitive tasks by food restriction

Temporary food restriction affects strain differences for behavioral phenotypes in the inbred strains of mice C57BL/6 (C57) and DBA/2 (DBA). Since food restriction is a routine procedure to motivate learning, we evaluated its influence on differences for spatial and non-spatial discrimination between these strains of mice by using two non-associative tasks: the Spatial Novelty Test (SNT) and the Spontaneous Object Recognition Test (SORT). The results confirmed the poor performance of the DBA mice in SNT. Nonetheless, DBA mice were perfectly able to recognize the novel object in SORT. By contrast, C57 mice were good performers in SNT but failed to recognize a novel object in SORT. Finally, food restriction selectively improved C57 performance in SNT and DBA performance in SORT. These results support the view that a food restricting procedure enhances strain differences for discrimination of configurational information.     

Operationalizing the "vulnerability" and "stress" components of the hopelessness theory of depression: a multi-wave longitudinal study

The current study tested of the diathesis-stress component of the hopelessness theory (HT) using (1) a "weakest link" approach towards operationalizing vulnerability (e.g., an individual is as vulnerable to depression as his/her most depressogenic inferential style-DIS) and (2) an idiographic approach towards operationalizing high levels of stress. The procedure involved an initial assessment during which participants completed measures assessing DISs and depressive symptoms. The procedure also involved a series of eight follow-up assessments, occurring every 6 weeks, during which depressive symptoms and hassles were assessed. Hypotheses were tested in two samples of adults (i.e., adults diagnosed with a current MDE and adults diagnosed with a past MDE at Time 1). In line with hypotheses, in both samples, depressogenic weakest links were associated with greater elevations in depressive symptoms following elevations in hassles. At the same time, equally strong support was obtained for the HT when stress was operationalized from a nomothetic perspective and when vulnerability was operationalized as a DIS about causes (but not consequences or self).     

Effects of visual environment on quiet standing by young and old adults

The authors manipulated the circumstances in which individuals are typically embedded when standing upright by manipulating the intensity of light and the stationary structure of the environment. They expected that the manipulations would affect 12 older participants (aged 65-82 years) more than it would 12 younger participants (aged 22-24 years). Linear (e.g., total path length) and nonlinear (e.g., maximum line length of recurrent points in phase space) measures of the center of pressure time series confirmed that expectation. Moreover, for some measures, there was a suggestion that participants' visual contrast sensitivity (an index of neurophysiological age) was a more important contributing factor overall than was their chronological age. In the Discussion, the authors highlight the significance of interactive effects of environmental, organismic, and task constraints on quiet standing.     

Italian developmental dyslexic and proficient readers: where are the differences?

Italian dyslexic children are characterized by a pervasive reading speed deficit, with relatively preserved accuracy. This pattern has been associated with predominant use of the nonlexical reading procedure. However, there is no evidence of a deficit in the lexical route of Italian dyslexics. We investigated both lexical and nonlexical reading procedures in dyslexic children through two marker effects, namely, the word frequency effect and the effect of contextual grapheme-to-phoneme conversion rules. Although dyslexics were slower and less accurate than controls, they were affected by word frequency, grapheme contextuality, and their interaction in a similar manner as average readers. These results show the use of lexical reading in Italian dyslexics, and refute the claim of a deficit in whole-word processing with consequent over-reliance on the nonlexical route.     

The joint

Some concave volumes are perceived as compositions of joined objects. Joined objects are optically undetermined, being compatible with three possible solutions: an empty intersection volume bounded by two indented objects; an intersection volume entirely filled-in by parts of two indented objects; a totally convex object joined to an indented object (the solution preferred by most perceivers). Knowledge of material penetrability does not predict 3D amodal completion. To identify relevant factors we selected different compositions and ran a multiple-regression analysis of completion choices. After eliminating colour, we considered six spatial factors: relative position along the vertical, relative size, orientation, proximity to the observer, minimization of completed parts, support relationship. The first two factors played a major role. The comparison of choices by upright versus inverted observers indicated that relative position along the vertical depends more on gravitational than egocentric coordinates. In conclusion, when relative spatial position and relative size cooperate, amodal completion of intersecting solids generates strong effects, which can overcome logical expectations.     

Neural circuitry underlying pain modulation: expectation,hypnosis, placebo

The ability to predict the likelihood of an aversive event is an important adaptive capacity. Certainty and uncertainty regarding pain cause different adaptive behavior, emotional states, attentional focus, and perceptual changes. Recent functional neuroimaging studies indicate that certain and uncertain expectation are mediated by different neural pathways-the former having been associated with activity in the rostral anterior cingulate cortex and posterior cerebellum, the latter with activation changes in the ventromedial prefrontal cortex, mid-cingulate cortex and hippocampus. Expectation plays an important role not only in its modulation of acute and chronic pain, but also in other disorders which are characterized by certain expectation (specific phobias) or uncertain expectation (generalized anxiety disorder) of aversive events.     

Object temporal connotation

Recent studies show that what connotes an object is first of all a certain spatio-temporal structure. In this paper we describe some of the temporal features characterizing the temporal structure of objects: pre-existence, persistence, conservation of identity in spite of perceptive discontinuity, surviving changes in colour, size, and shape. We argue that time is an indispensable attribute for every type of object and briefly discuss the implication of this view with respect to a specific neuropsychological syndrome: unilateral spatial neglect.     

Evidence for a double dissociation between spatial-simultaneous and spatial-sequential working memory in visuospatial (nonverbal) learning disabled children

The paper describes the performance of three children with specific visuospatial working memory (VSWM) impairments (Study 1) and three children with visuospatial (nonverbal) learning disabilities (Study 2) assessed with a battery of working memory (WM) tests and with a number of school achievement tasks. Overall, performance on WM tests provides evidence of a double dissociation between spatial-simultaneous processes, underpinning the memorization item positioning in a spatial configuration, and spatial-sequential processes, which allow memorization of the presentation order. In both groups of children of the two studies, a selective impairment either on spatial-sequential or on spatial-simultaneous working memory tasks was observed. These data support the existence of -simultaneous and -sequential modality-dependent processes in visuospatial working memory and confirm the importance of distinguishing between different subtypes of visuospatial (nonverbal) learning-disabled children.     

Orthographic complexity and word naming in Italian: Some words are more transparent than others

Italian is a language with a transparent orthography in which printed words can be translated into the correct sequence of phonemes using a limited set of rules. The rules of letter—sound conversion are, however, simpler for some letters than for others: The pronunciations of sequences involving the lettersc andg are determined by complex (i.e., context-sensitive) rules that depend on the letters that follow them. In this article, we report two experiments in which Italian participants read aloud words containing simple or complex letter—sound conversion rules. In Experiment 1, we found that words containing complex rules were read more slowly than words containing simple, noncontextual rules. In Experiment 2, we found that the effect of rule complexity on naming speed held for low-frequency words but not high-frequency words. The results are interpreted in terms of a dual-route model in which rule complexity effects arise from sublexical procedures that are more involved in reading low-frequency words than high-frequency words. The experimental material used in this study may be downloaded from www.psychonomic.org/archive.     

Change in children's understanding of others' intentional actions

The study investigated children's intention understanding using a longitudinal design. Thirty-two Italian children were tested on the 'Demonstration of Intention' in the Re-enactment paradigm devised by Meltzoff (1995a), at two ages. Mean age was 12 months at the first session and 15 months at the second session. Previous research by Meltzoff showed that 18-month-olds are able to re-enact what the adult intended to do, when an adult tried but failed to perform certain target acts. Bellagamba and Tomasello (1999) found that, compared to 18-month-olds, 12-month-olds are less able to imitate unsuccessful goal-directed actions. The current study had two main goals. The first was to replicate earlier findings on intention understanding in 12- and 15-month-olds longitudinally assessed. The second goal was to analyse which actions children perform when not producing the target act. A coding scheme was devised to evaluate these non-target actions. Results confirmed previous findings, i.e. children's tendency to produce the target act was higher at an older age. At a younger age the most frequent response was 'undifferentiated manipulation' of target objects, followed by 'approximation to the target action'. Since children differed in their intention understanding performance at the first session, we decided to check whether these individual differences remained stable at the second session. Individual children with high intention understanding performance at 12 months tended to remain high at 15 months of age.