A computational model of the Simon effect

Even though stimulus location is task irrelevant, reaction times are faster when the location of the stimulus corresponds with the location of the response than when it does not. This phenomenon is called the Simon effect. Most accounts of the Simon effect are based on the assumption that it arises from a conflict between the spatial code of the stimulus and that of the response. In this paper a computational model of this hypothesis is presented. It provides a computationally explicit mechanism of the Simon effect. Consistent with human performance, the model provides reaction times that indicate both an advantage for the ipsilateral, corresponding response (i.e., facilitation) and a disadvantage of the contralateral, noncorresponding response (i.e., inhibition). In addition, the model accounts for the fact that the size for the effect depends on task difficulty.     

Is there a modality effect? Evidence for visual recency and suffix effects

In Experiment 1, four groups of 16 subjects performed ordered recall of six-syllable lists in both suffix and nonsuffix conditions. Sequential presentation of the lists varied for each group. In the auditory presentation, the syllables were delivered from one location only and were read aloud by the subjects. For the visual, spatially nondistributed presentation, the syllables appeared in one location only and were read silently. For visual, spatially distributed presentations, the syllables were spread out either vertically or horizontally and were read silently. Very robust recency and suffix effects were found in the auditory presentation, as well as in visual, spatially distributed presentations. In Experiment 2, 16 subjects performed ordered recall of visually presented lists with the items spread out vertically and conflicting spatial and temporal orders. A reliable recency effect was found for the final block of trials. In Experiment 3, 16 subjects performed ordered recall in the same conditions as in Experiment 2, except that they were instructed to recall the temporal order in which the spatial positions would be filled in. A bow-shaped curve and a strong recency effect were obtained.     

Societal and individualistic drivers as predictors of organic purchasing revealed through a portrait value questionnaire (PVQ)‐based inventory

• The Schwartz's Portrait Value Questionnaire (PVQ) has extensively been used in personal values research. The present survey validates and tests in a value‐based segmentation task a 17‐item PVQ‐based inventory that includes consumer values related to organic food purchasing, using a nationally representative sample of 1043 Greek consumers. The main assumption of the survey is that consumer segments that place more emphasis on specific organic food‐related values would present different magnitude of beliefs and purchasing behaviour towards organic products. Two 2nd‐order value factors (named ‘individualistic’ and ‘societal’, respectively) emerged from exploratory and confirmatory factor analyses comprising 14 out of the initial 17 PVQ values. In the next phase of the analysis, hierarchical clustering was implemented based on those factors. Through the clusters emerged, a clear relation between consumers' ‘societal’ (universalism and benevolence) value similarity, higher frequency of organic purchasing and higher likelihood of organic‐related beliefs was clearly identified. This fact supports the applicability of the PVQ typology in predicting consumer behaviour in various product contexts.

Copyright © 2008 John Wiley & Sons, Ltd.     

The A Theory Of Magnitude (ATOM) model in temporal perception and reproduction tasks

According to the A Theory of Magnitude (ATOM) model, time, numbers and space are processed by a common analog magnitude system. The model proposes that time, numbers and space are influenced by each other. Indeed, spatial-temporal (STEARC effect), spatial-numerical (SNARC effect) and temporal-numerical (TiNARC effect) interactions have been observed. However, the processing of time, numbers and space has not yet been studied within the same experimental procedure. The goal of this study is to test the ATOM model using a procedure in which time, numbers and space are all present. The participants were asked to perform temporal estimation (Experiment 1) and reproduction (Experiment 2) tasks in two different conditions, with either numbers or letters as stimuli. In Experiment 1, significant STEARC, SNARC and TiNARC effects were found in general and when numbers were presented. Moreover, a significant triple interaction between space, time and magnitude was observed, indicating associations between the left key, short duration and small magnitudes, as well as between the right key, long duration and large magnitudes. These results were similar in reaction times and accuracy. In Experiment 2, the results of reproduction times mirrored the previous data but the triple interaction was not found on reproduction times. Considering the temporal accuracy, the STEARC, SNARC and TiNARC effects as well as triple interaction were found. The results seem to partially confirm the ATOM model, even if differences between temporal tasks should be posited.     

The Maternal lineage: identification,desire and transgenerational issues

In this paper I argue that close attention should be paid to the changes that have been taking place in the National Health Service over the last 15 years as a result of governmental initiatives. The identification of the direction that the recent health reforms have been taking should allow us to draw significant conclusions regarding the possible fate that the NHS is facing in the not‐too‐distant future. The introduction of the internal market in health care, the Private Finance Initiative, private Diagnostic & Treatment Centres and Foundation Trusts may indicate that the privatization of the NHS has begun in earnest. The relevance of such considerations to all NHS workers and users needs to be appreciated, as it may go some way towards answering the important question of what kind of NHS we will be having and using in the future. The implications for the NHS in general, and for psychotherapy services in particular, of the insidious but invasive process of privatization inherent in the ongoing changes in the structure and funding of the NHS are discussed.     

A Tower Unto Heaven: Toward an Expanded Framework for Psychopathology

I respond to commentaries on my target article “An Evolutionary Life History Framework for Psychopathology.” I start by addressing criticism of my basic assumptions about life history strategies and their implications for individual differences in human behavior. Next, I examine the theoretical structure of the proposed framework and respond to the commentators’ challenges to its generality and flexibility. I show how the framework can be expanded to include multiple levels of analysis and to integrate behavioral control with neurological functionality; I also reinterpret the recent finding of a general factor of psychopathology in the context of the expanded framework. In the last section I discuss specific psychopathological conditions, namely attention deficit/hyperactivity disorder, borderline personality disorder, substance abuse, autism spectrum disorders, schizophrenia spectrum disorders, obsessive-compulsive disorder, eating disorders, and depression. For each condition, I reply to the commentators’ criticism of my life history analysis, integrate their suggestions and insights, highlight the present weaknesses of the theory, and indicate promising directions for future research.     

Gender Hierarchy in the Space: The Role of Gender Status in Shaping the Spatial Agency Bias

According to the Spatial Agency Bias (SAB), more agentic groups (men) are envisioned to the left of less agentic groups (women). This research investigated the role of social status in shaping the spatial representation of gender couples. Participants were presented pairs consisting of one male and one female target who confirmed gender stereotypes. The status of the targets in each pair was systematically varied (high-status vs. low-status job). Participants chose the target order (female/male vs. male/female) they preferred. In line with gender-status expectations (male: high-status, female: low-status), a male in a high-status job led to a spatial arrangement that favored the male/female order, regardless of the status of the female target. The female/male order was favored only when the female had a high-status job and the male a low-status job. No SAB occurred for pairs in which both targets displayed low-status jobs. The implications of status for the SAB are discussed.     

Self-motion perception and vestibulo-ocular reflex during whole body yaw rotation in standing subjects: the role of head position and neck proprioception

Self-motion perception and vestibulo-ocular reflex (VOR) were studied during whole body yaw rotation in the dark at different static head positions. Rotations consisted of four cycles of symmetric sinusoidal and asymmetric oscillations. Self-motion perception was evaluated by measuring the ability of subjects to manually track a static remembered target. VOR was recorded separately and the slow phase eye position (SPEP) was computed. Three different head static yaw deviations (active and passive) relative to the trunk (0°, 45° to right and 45° to left) were examined. Active head deviations had a significant effect during asymmetric oscillation: the movement perception was enhanced when the head was kept turned toward the side of body rotation and decreased in the opposite direction. Conversely, passive head deviations had no effect on movement perception. Further, vibration (100 Hz) of the neck muscles splenius capitis and sternocleidomastoideus remarkably influenced perceived rotation during asymmetric oscillation. On the other hand, SPEP of VOR was modulated by active head deviation, but was not influenced by neck muscle vibration. Through its effects on motion perception and reflex gain, head position improved gaze stability and enhanced self-motion perception in the direction of the head deviation.     

The rubber hand illusion in a mirror

In the rubber hand illusion (RHI) one’s hand is hidden, and a fake hand is visible. We explored the situation in which visual information was available indirectly in a mirror. In the mirror condition, compared to the standard condition (fake hand visible directly), we found no reduction of the RHI following synchronised stimulation, as measured by crossmanual pointing and by a questionnaire. We replicated the finding with a smaller mirror that prevented visibility of the face. The RHI was eliminated when a wooden block replaced the fake hand, or when the hand belonged to another person or mannequin. We conclude that awareness of the reflection is the critical variable, despite the distant visual localisation of the hand in a mirror and the third-person perspective. Stimuli seen in a mirror activate the same response as stimuli seen in peripersonal space, through knowledge that they are near one’s body.