Delayed Onset of Inhibition of Return in Visual Snow Syndrome.

Visual snow syndrome (VSS) is a complex, sensory processing disorder. We have previously shown that visual processing changes manifest in significantly faster eye movements toward a suddenly appearing visual stimulus and difficulty inhibiting an eye movement toward a non-target visual stimulus. We propose that these changes reflect poor attentional control and occur whether attention is directed exogenously by a suddenly appearing event, or endogenously as a function of manipulating expectation surrounding an upcoming event.

The Psychiatric Symptomology of Visual Snow Syndrome.

To characterise the psychiatric symptoms of visual snow syndrome (VSS), and determine their relationship to quality of life and severity of visual symptoms. One hundred twenty-five patients with VSS completed a battery of questionnaires assessing depression/anxiety, dissociative experiences (depersonalisation), sleep quality, fatigue, and quality of life, as well as a structured clinical interview about their visual and sensory symptoms. VSS patients showed high rates of anxiety and depression, depersonalisation, fatigue, and poor sleep, which significantly impacted quality of life.

Eye movement characteristics provide an objective measure of visual processing changes in patients with visual snow syndrome.

Visual snow syndrome (VSS) is a poorly understood neurological disorder that features a range of disabling sensory changes. Visual processing changes revealed previously in VSS appear consistent with poor attentional control, specifically, with difficulty controlling environmentally driven shifts of attention. This study sought to confirm this proposal by determining whether these changes were similarly evident where attention is internally driven.

Ocular motor measures of visual processing changes in visual snow syndrome.

Objective: To determine whether changes to cortical processing of visual information can be evaluated objectively using 3 simple ocular motor tasks to measure performance in patients with visual snow syndrome (VSS).

Methods: Sixty-four patients with VSS (32 with migraine and 32 with no migraine) and 23 controls participated. Three ocular motor tasks were included: prosaccade (PS), antisaccade (AS), and interleaved AS-PS tasks.

Executive control deficits correlate with reduced frontal white matter volume in multiple sclerosis.

: Executive control deficits are frequently reported in patients with multiple sclerosis (MS). We have previously proposed that in the context of competing automatic and volitional processes, such deficits may in part reflect poor resolution of response conflict. This study aimed to investigate the neuropathological underpinnings of executive control deficits in MS, focusing on the frontostriatal system proposed to mediate executive control.

Characterization of inhibitory failure in Multiple Sclerosis: Evidence of impaired conflict resolution.

Introduction: Inhibitory control deficits are frequently reported in Multiple Sclerosis (MS), although it is unclear whether these deficits represent a global or process-specific failure. Notably, most models of inhibitory control recognize at least two dissociable processes, the most consistent being: (a) the inhibition of a dominant response: response suppression, and (b) the inhibition of a dominant response and initiation of a nondominant response: executive control. This study aimed to ascertain the processes underlying inhibitory failure in MS.