Collinear Motion Strengthens Local Context in Visual Detection.

Detection of elongated objects in the visual scene can be improved by additional elements flanking the object on the collinear axis. This is the collinear context effect (CE) and is represented in the long-range horizontal connection plexus in V1. The aim of this study was to test whether the visual collinear motion can improve the CE.

Electrophysiological Modulation in an Effort to Complete Illusory Figures: Configuration, Illusory Contour and Closure Effects.

Figure recognition process: From the coarse configuration standing from the background to the closure of a meaningful shape, was investigated by ERP technique. ERP components at different latencies from stimulus onset allowed to tap into the figure recognition process at discrete time-points when different cognitive operations take place. In this study, we present two experiments where the support-ratio (SR) of illusory figures was manipulated to vary continuously the recognition of geometrical figures.

New ERP Methods Tailored Onto Single Subject Neuroanatomical Variability.

Gebodh and coworkers present an innovative method for strengthening the reliability with which event-related potential (ERP) components are recorded. By tailoring the experimental design to the neuroanatomical singularity of each observer, this method provides more robust and cleaner data.

Vigorous orientation signal propagates best from collinear motion.

In the present study, the Poggendorff illusion was tested with four types of stimuli: A moving dot, a moving bar parallel to the inducing lines, a moving bar collinear to the motion trajectory, and static bars as in the classic illusion. Psychometric functions of the alignment task showed that the collinear bar, where orientation and motion trajectory matched, yielded the best alignment performance almost eliminating the illusion; the vertical bar, on the contrary, showed the worst alignment, finally the dot and the static bars led to intermediate alignments. These results demonstrate the interaction between orientation and motion trajectory that likely takes place in the primary visual cortex (V1) where these two signals might be modulated by top-down activity from higher order areas such as the middle temporal (MT).

Unconscious priming by illusory figures: the role of the salient region.

In this study we provide evidence that unconscious priming can be obtained as a result of the processing of the salient region (SR) of illusory figures and without that of illusory contours (ICs). We used a metacontrast masking paradigm where illusory figures were masked by real figures. In Experiment 1 we found a clear priming effect when participants were asked to discriminate between square and diamond masks preceded by congruent or incongruent illusory square or diamond primes.

Interhemispheric transfer of spatial and semantic information: electrophysiological evidence.

The goal of this study was to cast light on the existence of functional callosal channels for the interhemispheric transfer (IHT) of spatial and semantic information. To do so, we recorded event-related potentials in healthy humans while performing a primed odd-even discrimination task. Targets were visually presented numbers preceded by single-letter primes signaling the probable presentation of an odd or an even number.

Does subliminal visual perception have an error-monitoring system?

There is substantial evidence that subliminal stimuli, i.e. stimuli that cannot be perceived consciously, may influence visually guided human behaviour.

Lateralized readiness potential elicited by undetected visual stimuli.

Visual stimuli undetected by normal subjects as a result of masking procedures can nonetheless activate response preparation in motor areas and yield a motor response. An unanswered question is whether the same holds for undetected subliminal stimuli that are not responded to. To answer this question, in this study normal subjects were tested on a simple visual reaction time task with stimuli above, at, or below the psychophysical threshold while the lateralized readiness potential (LRP), i.

Reasons for substance use and vulnerability factors in patients with substance use disorder and anxiety or mood disorders.

This cross-sectional study examined the reasons for substance use and the presence of vulnerability factors such as substance sensitivity, sensation seeking, and symptoms related to the attention deficit hyperactivity disorder (ADHD) in patients with substance use disorder (SUD) and comorbid mood and anxiety disorders by using the Structured Clinical Interview for the Spectrum of Substance Use (SCI-SUBS), a novel instrument designed to explore the spectrum of substance use and its clinical correlates. Study participants included 61 patients with SUD and mood or anxiety disorder, and two comparison groups including 35 patients with SUD only and 50 controls not in treatment for mental disorders or SUD. We found that patients with co-morbid mood or anxiety disorder had significantly higher scores on the SCI-SUBS domains 'substance sensitivity' and 'self-medication' as compared to those with SUD only.

Dual diagnosis and quality of life in patients in treatment for opioid dependence.

This study examined the relationship between quality of life (QOL) and dual diagnosis among patients in treatment for opioid dependence. The study sample includes 57 patients with opioid dependence alone (OD) and 41 with opioid dependence and a psychiatric axis-I disorder (DD), recruited in 2001 and 2004 at the Drug Addiction Services (SerT) of Bolzano and Pontedera (Italy). Participants were 73.