Social effects on rat spatial choice in an open field task

Pairs of rats foraged in trials either together or separately in an open field apparatus for pellets hidden in discreet locations in a 5 × 5 matrix. Trial duration was either 1 or 4 min. The tendency to choose locations that had earlier been visited by another rat was examined by comparing the choices made in the presence and absence of the other rat. Rats avoided visits to locations that had earlier been visited by the other rat, but only if they had also visited the same location earlier in a short duration trial. This pattern of results is consistent with earlier findings from experiments using the radial arm maze. Furthermore, when rats did visit locations that had earlier been visited by the other rat in a long duration trial, they tended to be locations that had been visited longer ago by the other rat than would be expected. This suggests a forgetting function for social memories. These data provide evidence that the social memory reported in earlier studies using the radial-arm maze can be found in other experimental paradigms and that at least some of its properties are common in the two paradigms.     

Human responding with mutual reinforcement: Baseline and effects of an intervention1

Pressing a key by one undergraduate provided another undergraduate with points exchangeable for money, and vice versa. Four types of response patterns were found. Points were often delivered with a delay from the last response or with no response. When a contingency that responses lost points (punishment) was added to participants who had emitted more responses than the partner had, their response rates decreased while the rates of their partners increased. These results demonstrate that, under the contingency of mutual reinforcement: (a) response patterns that had occurred between monkeys were replicated between humans; (b) obtained response‐reinforcer relations were different from those generally programmed in the basic reinforcement schedules; and (c) the behavior of the participant was controlled by changing the behavior of the partner.     

Spatial probability cuing and right hemisphere damage

In this experiment we studied statistical learning, inter-trial priming, and visual attention. We assessed healthy controls and right brain damaged (RBD) patients with and without neglect, on a simple visual discrimination task designed to measure priming effects and probability learning. All participants showed a preserved priming effect for item color. Contrary to healthy controls and RBD participants without neglect, RBD participants with neglect did not show positional priming and both RBD groups learned the underlying spatial probability distribution of target locations to a lesser degree. To see if the latter deficiency could be improved, we tested a patient with long standing chronic spatial neglect on three separate days and observed improved identification times for left sided, high probability, targets. In summary, we found preservation of priming per se in people with spatial neglect. However, this was only clearly demonstrable for color priming and not for positional priming. Associated with this impairment was a difficulty in learning the overall statistical structure of target locations. In a patient with severe persistent neglect we were able to demonstrate that the deficit in statistical learning was not absolute, as this subject improved his identification times for targets appearing in high probability regions of the test display.     

Effects of irrelevant object structure on early attention deployment

Event-related potential (ERP) studies have suggested that Gestalt principles or grouping factors in a visual scene modulate attention deployment in early visual processing. The present study examined the effects of an extrinsic grouping factor, region commonality, on early ERP spatial attention. Effects of sex were also explored, since the processing of task-irrelvant objects may differ between the sexes. Twenty-four participants were required to discriminate one side of rapidly-presented bilateral letters, and attention effects were indexed by hemispheric lateralization accroding to attended visual fields. In results, an early P1 attention effect (70–110 ms) increased when the letters were surrounded by an object, compared to the control stimulus without a complete object, and this result was more prominent in women than in men. The present study demonstrates that visual object and sex differences play a novel role at very early cortical stages of processing in attention deployment to a task-irrelevant visual structure.     

Changes in verbalizations during sandplay: an empirical study

This is a quantitative study of an 11-year-old boy diagnosed with major depression who in all but one session made a sandplay. A computerized system was used to analyse the written verbalizations on four dimensions of positive and negative: emotions, contracts (psychosocial agreements, relationships, etc.), performance (behaviour) and rewards. It was hypothesized that the verbalizations made by the patient (recorded by the therapist) would become more positive and less negative during the course of therapy. The positive and negative values of the four dimensions were correlated with the session number. This was supported on two (performance & contract) of the four positive dimensions (statistically significant). The hypothesis that the negative dimensions would become less negative was supported on all four dimensions (statistically significant). Thus, six of the eight hypotheses were supported. This uninvestigated area of research illustrates verbal interactions between patient and therapist were an important aspect of sandplay therapy. Through reanalysing the sessions for quantitative content, written recording of direct quotes and observation of behaviour, data was entered into a valid and reliable coding system to quantitatively analyze the verbalizations. This analysis of verbalizations of the patient and observations made by the therapist indicates sandplay therapy is multifaceted.     

A unity of the self or a multiplicity of locations? How the graphesthesia task sheds light on the role of spatial perspectives in bodily self-consciousness

Integrating multisensory stimuli from a self-centred perspective is crucial for the unity of the self. On the other hand, understanding external space and communicating spatial knowledge with others necessitate the adoption of decentred perspectives. How do we juggle these two requirements? In this article, we review those studies that have used the graphesthesia task in order to investigate the perspectives that people adopt when interpreting ambiguous tactile symbols (e.g., b, d, p, and q). With such ambiguous symbols, self-centred and decentred perspectives conflict with one another. The results reviewed here reveal that the perspectives adopted vary significantly with spatial, personal, and interpersonal factors. Such findings suggest that the self can adopt a multiplicity of spatial locations. However, the unity of the self can partly be explained by the predominance of a head-centred perspective. On the other hand, perspective-taking abilities contribute to the distinction between self and others, reinforcing self-consciousness.     

Reconstructing maps from text

Previous research has demonstrated that Distributional Semantic Models (DSMs) are capable of reconstructing maps from news corpora (Louwerse & Zwaan, 2009) and novels (Louwerse & Benesh, 2012). The capacity for reproducing maps is surprising since DSMs notoriously lack perceptual grounding. In this paper we investigate the statistical sources required in language to infer maps, and the resulting constraints placed on mechanisms of semantic representation. Study 1 brings word co-occurrence under experimental control to demonstrate that standard DSMs cannot reproduce maps when word co-occurrence is uniform. Specifically, standard DSMs require that direct co-occurrences between city names in a corpus mirror the proximity between the city locations in the map in order to successfully reconstruct the spatial map. Study 2 presents an instance-based DSM that is capable of reconstructing maps independent of the frequency of co-occurrence of city names.     

A purely power-space association without spatial and strategic biases

Previous studies have shown that powerful and powerless concepts are metaphorically associated with top and bottom spaces respectively. However, this association might be contaminated by spatial and strategic biases due to the involvement of spatialized stimuli or responses. It is unknown whether power by itself can automatically activate spatial representations. To eliminate spatial and strategic biases, Experiment 1 separately presented power and spatial stimuli at the center of the screen, and participants had to classify power words and HIGH/LOW labels (Experiment 1a) or indicate up/down arrows (Experiment 1b) using a single key and follow different response rules that were combined with a Go/no-go task. Experiment 2 replicated the non-spatialized design but used an implicit power judgment task. Based upon the non-spatialized method, the results provide the first evidence that a power-space association effect still exists when eliminating spatial and strategic biases, revealing the nonconscious spatial nature of power.