Insensitivity of visual short-term memory to irrelevant visual information

Several authors have hypothesized that visuo-spatial working memory is functionally analogous to verbal working memory. Irrelevant background speech impairs verbal short-term memory. We investigated whether irrelevant visual information has an analogous effect on visual short-term memory, using a dynamic visual noise (DVN) technique known to disrupt visual imagery (Quinn & McConnell, 1996b). Experiment 1 replicated the effect of DVN on pegword imagery. Experiments 2 and 3 showed no effect of DVN on recall of static matrix patterns, despite a significant effect of a concurrent spatial tapping task. Experiment 4 showed no effect of DVN on encoding or maintenance of arrays of matrix patterns, despite testing memory by a recognition procedure to encourage visual rather than spatial processing. Serial position curves showed a one-item recency effect typical of visual short-term memory. Experiment 5 showed no effect of DVN on short-term recognition of Chinese characters, despite effects of visual similarity and a concurrent colour memory task that confirmed visual processing of the characters. We conclude that irrelevant visual noise does not impair visual short-term memory. Visual working memory may not be functionally analogous to verbal working memory, and different cognitive processes may underlie visual short-term memory and visual imagery.     

Detecting concealed information with reaction times: Validity and comparison with the polygraph

The Concealed Information Test is used to assess recognition of information that the examinee cannot or does not want to reveal. Physiological measures recorded with the polygraph have shown to be highly valid measures of concealed information. Research suggests that a reaction‐time (RT) based test may also successfully reveal concealed information. Due to its simplicity, an RT‐based test has great advantages for applied testing. In the present study, we assessed the validity of the RT‐based test for concealed information detection, and compared its discriminative power with the polygraph. Thirty two participants in a feigned amnesia study were promised a financial reward when successfully concealing autobiographical information. Participants performed an RT‐based test, and a polygraph test. The data support the validity of the RT‐based test for concealed information detection, and indicate its discriminative power is similar to the polygraph. Our data confirm the potential of the RT‐based test. Copyright © 2009 John Wiley & Sons, Ltd.     

The Expanded Version of the Inferential Confusion Questionnaire: Further Development and Validation in Clinical and Non-Clinical Samples

The current study represents the further development and validation of an expanded version of the Inferential Confusion Questionnaire (ICQ-EV) in non-clinical and clinical samples. Inferential confusion seems to be particularly relevant to Obsessive-Compulsive Disorder (OCD) and is defined as a failure to recognize the unrealistic nature of obsessions due to a subjective form of reasoning. Factor analysis of the item-set of the ICQ-EV indicated a one-dimensional solution in non-clinical and clinical samples. It was hypothesized that inferential confusion as measured by the ICQ-EV would be particularly relevant to participants with OCD. Results confirmed convergent validity with strong relationships between the ICQ-EV and obsessive-compulsive symptoms in all samples independent of other cognitive domains and general distress. In addition, those with OCD scored higher on the ICQ-EV than non-clinical controls and a mixed anxiety disorder group so confirming group-criterion validity. Finally, the ICQ-EV also showed clinical validity with change in ICQ-EV scores during treatment significantly related to successful treatment outcome.     

Expanding MEL response box to accommodate up to 16 external buttons

Micro Experimental Laboratory (MEL) is a widely used software package developed for the automation of psychological experiments. This report presents a simple way to implement and use an expanded MEL response box that accommodates up to 16 external switches. Hardware and software considerations are reviewed, and relevant MEL code is provided. This includes a simple algorithm that permits the reading of multiple responses within a single trial.     

Deficit in phonological processes: a characteristic of the neuropsychological profile of children with NF1

Learning disabilities are one of the most frequent complications of neurofibromatosis type 1 (NF1) in children. Studies of the effects of the neurocognitive deficit on academic performance are relatively rare, owing to the small size of the populations concerned. However, research is needed to develop effective rehabilitation programs. In the present study, we explored the impact of a possible phonological deficit on the reading abilities of children with NF1. A multicenter, cross-sectional study was conducted in France on two groups of 75 children with or without NF1 aged 8–12 years, matched for age, sex, handedness, and reading level. All participants underwent a neuropsychological evaluation to assess their general cognitive level, reading skills, phonological processes, visuoperceptual abilities, and attentional capacity. Phonological skills were assessed by means of two phonological awareness tasks and one short-term memory task. In the group of children with NF1, 41% had reading difficulties. Phonological processes were impaired in this group, compared with the children without NF1. Similar differences were found for a phoneme deletion task after adjustment for reading difficulties, IQ level, and visuoperceptual abilities. Phonological awareness, but not phonological short-term memory, was impaired in children with NF1, and not just those whose reading was impaired. Results suggest that children with NF1 have a phonological awareness deficit, whatever their reading level. Identification of reduced phonological skills may warrant the implementation of a specific rehabilitation program before early reading difficulties emerge.     

Improvement of mental imagery after prism exposure in neglect: a case study

Previous work has shown that various symptoms of unilateral neglect, including the pathological shift of the subjective midline to the right, may be improved by a short adaptation period to a prismatic shift of the visual field to the right. We report here the improvement of imagined neglect after prism exposure in a patient with a left unilateral neglect. Despite a strong neglect observed for mental images as well as for conventional tests, the mental evocation of left-sided information from an internal image of the map of France map was fully recovered following prism adaptation to the right. This improvement could not be explained by the alteration of visuomotor responses induced by the prism adaptation. Prism adaptation may therefore act not only on sensory-motor levels but also on a higher cognitive level of mental space representation and/or exploration.     

COVERT ORIENTING IN THE SPLIT BRAIN REVEALS HEMISPHERIC SPECIALIZATION FOR OBJECT-BASED ATTENTION

Abstract— Theones in cognitive science have debated whether visual selective attention is a space-based or object-based process To investigate this issue, we applied a new experimental paradigm that permits the simultaneous measurement of both space-based and object-based attention to a split-brain patient with disconnected cerebral hemispheres The data demonstrate both space-based and object-based components to the allocation of attention, and reveal that the two processes have different neural substrates These findings are related to previous research on split-brain and unilateral parietal patients