Shock as a signal for shock or no-shock: a feature-negative effect in conditioned suppression.

Rats were trained in conditioned suppression discriminations where shock at the beginning of a trial signaled either shock or no-shock at the end of the trial. In the shock-positive condition, shock at the beginning of a presentation of white noise signaled that noise would end with shock; noise that did not begin with shock did not end with shock. In the shock-negative discrimination, shock at the beginning of noise signaled that noise would not end with shock; presentations of noise that did not begin with shock ended with shock. In shock-random training, shock at the beginning of noise did not reliably signal whether the noise presentation would or would not end with shock. Most subjects in shock-negative training quickly developed a differential pattern of suppression on positive (shock reinforced) trials and no suppression on negative (nonreinforced) trials. The shock-positive discrimination was much more difficult to establish and was not acquired by the majority of the rats. This "feature-negative" effect is a clear exception to the general superiority of feature-positive learning commonly observed in discriminations based on a single distinguishing feature. The results are discussed in terms of Pavlovian stimulus-shock contingencies in the shock-positive and shock-negative paradigms, which appear to favor rapid development of the shock-negative discrimination.     

Components representation of negative numbers: Evidence from auditory stimuli detection and number classification tasks

Past research suggested that negative numbers could be represented in terms of their components in the visual modality. The present study examined the processing of negative numbers in the auditory modality and whether it is affected by context. Experiment 1 employed a stimuli detection task where only negative numbers were presented binaurally. Experiment 2 employed the same task, but both positive and negative numbers were mixed as cues. A reverse attentional spatial–numerical association of response codes (SNARC) effect for negative numbers was obtained in these two experiments. Experiment 3 employed a number classification task where only negative numbers were presented binaurally. Experiment 4 employed the same task, but both positive and negative numbers were mixed. A reverse SNARC effect for negative numbers was obtained in these two experiments. These findings suggest that negative numbers in the auditory modality are generated from the set of positive numbers, thus supporting a components representation.     

Visual working memory for dynamic objects: Impaired binding between object feature and location

In daily life, people frequently need to observe dynamic objects and temporarily maintain their representations in visual working memory (VWM). The present study explored the mechanism underlying the binding between perceptual features and locations of dynamic objects in VWM. In three experiments, we measured and compared the memory performance for feature-location binding of multiple dynamic and static objects. The results showed that the feature-location binding was impaired for the dynamic objects compared with the static objects. The impairment persisted when the global spatial configuration of the objects remained intact during the motion, as well as when the binding task was relatively easy, such as binding between single-feature objects and coarse locations. The results indicate that object features and locations are not maintained in VWM as well-integrated object files; rather, the formation of feature-location binding may require additional processes, which are disrupted by the constant change of locations in dynamic circumstances. We propose a consolidation process as possible underlying mechanism, and discuss factors that may influence the strength of feature-location binding in dynamic circumstances.     

Objects,pictures and words. Effects of representational format on four-year-olds’ quantity knowledge / Objetos,imágenes y palabras. Efectos del formato representacional en el conocimiento de la cantidad a los cuatro años

Abstract

This study explores whether and how different external representations of quantity influence the performance of four-year-old children when constructing sets of a given cardinal number. Three representations of quantity were presented (objects, pictures and number words) in an adaptation of the ‘Give-a-number’ task, in sets that contained 2–6 items. The results show that the use of pictures facilitated children’s performance with quantities of three and four. These results are discussed by analysing the cognitive demands of representational formats, in terms of dual representation and iconicity, and according to the magnitude of the quantities involved.     

The paradox between the numerically competent baby and the slow learning of two- to four-year-old children / La paradoja entre el bebé numéricamente competente y el lento aprendizaje de los niños de dos a cuatro años de edad

Abstract

Since the 1980s, numerous laboratory investigations have been arguing that infants are numerically competent. This work presents a critical review of this line of research. We propose that despite the repertoire of numerical abilities attributed to infants and the seemingly natural character of the very first numbers in the numerical series, the semiotic complexity of their use and comprehension poses a cognitive challenge that children undertake, motivated, supported and often guided by others. This challenge involves a high degree of semiotic organization of the material world as well as an ability to manage early sign systems, systems which children learn how to use during their first years of life and which form the platform on which numbers are based.     

Mathematical Abilities in Elementary School Children with Autism Spectrum Disorder

Although clinical practitioners often express concerns about the mathematical functioning of children with autism spectrum disorder (ASD), the field of mathematics remains a relatively unexplored topic in individuals with ASD. Moreover, research findings are fragmentary and hold inconclusive results. The present study aimed to examine whether grade 1 (aged 6–7 years) to 4 (aged 9–10 years) elementary school children with ASD scored significantly different from age‐adequate norms on mathematics. To this end, a multi‐componential approach of mathematics was used. Four domains of mathematics were assessed in 121 children with ASD: procedural calculation, number fact retrieval, word/language problems, and time‐related competences. All children attended general education classrooms, following the standard curriculum, and were coached by integrated educational services. Children with ASD showed a strength in word/language problems in second and fourth grade. There was evidence of a weakness for procedural calculation in first grade and for time‐related competences in first and third grade. In all other cases, average scores were shown. As such, results revealed a profile of strengths, average abilities, and weaknesses in mathematics and highlighted the importance of focusing on different domains of mathematics. Because a high variability in mathematical performance could be observed, we recommend an individual assessment when considering the mathematical trajectory of children with ASD. Copyright © 2015 John Wiley & Sons, Ltd.     

Extra‐powerful on the visuo‐perceptual space,but variable on the number space: Different effects of optokinetic stimulation in neglect patients

We studied the effects of optokinetic stimulation (OKS; leftward, rightward, control) on the visuo‐perceptual and number space, in the same sample, during line bisection and mental number interval bisection tasks. To this end, we tested six patients with right‐hemisphere damage and neglect, six patients with right‐hemisphere damage but without neglect, and six neurologically healthy participants. In patients with neglect, we found a strong effect of leftward OKS on line bisection, but not on mental number interval bisection. We suggest that OKS influences the number space only under specific conditions.     

At the root of the left–right asymmetries in spatial–numerical processing: From domestic chicks to human subjects

In this review, we discuss evidence showing that birds (Gallus gallus and Nucifraga columbiana) represent numerical magnitudes as being oriented from left to right. Subjects, trained to identify a target element (i.e. the 4th) in a series of sagittally oriented identical elements, when required to generalise on an identical series oriented spatially from left to right, correctly identified the target element “counting” from the left of the array. Moreover, chicks, when presented with sets of 5 vs. 10 or 6 vs. 9 imprinting objects, which were made to disappear one at a time behind one of two identical screens, spontaneously inspected the screen which occluded the larger set. Interestingly, chicks scored a higher percentage of correct choices when the larger of the two sets was on their right side. Similarities with the phenomenon of the spatially oriented (left to right) number line in humans are discussed. Animal models promise a fresh approach to the understanding of developmental mechanisms underlying the expression of knowledge, offering attractive arguments for doubting the uniqueness of human numerical cognition.     

Disruptions to number bisection after brain injury: Neglecting parts of the Mental Number Line or working memory impairments?

The aim of this study was to investigate the mechanisms underlying consistent directional number bisection bias in a chronic neuropsychological sample, not selected based on behaviour or lesion definitions. Patients completed a test battery that included measures of number bisection, line bisection, verbal working memory, visual-spatial working memory, egocentric neglect and allocentric neglect. Neither the neglect nor working memory measures were found to significantly correlate with number bisection. Furthermore, when outlier patients with very distinct number bisection biases were compared to patients who did not show any number bisection difficulties, no differences were found between the two groups on any of the other behavioural measures. We conclude that number bisection difficulties are not consistently based on any single deficit, be it neglect or working memory, and biases in number bisection should not be assumed to directly reflect problems in either of these areas.