Exploration of anomalous perceptual experiences in migraine between attacks using the Cardiff Anomalous Perceptions Scale.

Distortions in sensory experiences that precede a migraine attack have been extensively documented, the most well-known being the visual aura. Distortions in the experience of other senses are also reported as part of an aura, albeit less frequently, together with changes in the perception or ownership of the body or body parts. There are many examples of differences in aspects of visual perception between migraine and control groups, between attacks, but not as much on unusual experiences involving other senses, the sense of the body or the experience of the environment.

A Review of Motion and Orientation Processing in Migraine.

Visual tests can be used as noninvasive tools to test models of the pathophysiology underlying neurological conditions, such as migraine. They may also be used to track changes in performance that vary with the migraine cycle or can track the efficacy of prophylactic treatments. This article reviews the literature on performance differences on two visual tasks, global motion discrimination and orientation, which, of the many visual tasks that have been used to compare differences between migraine and control groups, have yielded the most consistent patterns of group differences.

A comparison of the effects of the colour and size of coloured overlays on young children's reading.

This study compared the effects of the colour and size of overlays on reading time, reading errors and on the clarity of text with young primary school children. The sample comprised a non-clinical, typical, sample from an East London primary school. One hundred and six children aged between four and seven years were asked to read 11 short passages of text (60 words) either with full page overlays or smaller reading rulers (53 in each group).

Links between global and local shape perception, coloured backgrounds, colour discrimination, and non-verbal IQ.

This study explored associations between local and global shape perception on coloured backgrounds, colour discrimination, and non-verbal IQ (NVIQ). Five background colours were chosen for the local and global shape tasks that were tailored for the cone-opponent pathways early in the visual system (cardinal colour directions: L-M, loosely, reddish-greenish; and S-(L + M), or tritan colours, loosely, blueish-yellowish; where L, M and S refer to the long, middle and short wavelength sensitive cones). Participants also completed the Farnsworth-Munsell 100-hue test (FM100) to determine whether performance on the local and global shape tasks correlated with colour discrimination overall, or with performance on the L-M and tritan subsets of the FM100 test.

Visual motion processing in migraine: Enhanced motion after-effects are related to display contrast, visual symptoms, visual triggers and attack frequency.

Background Visual after-effects are illusions that occur after prolonged viewing of visual displays. The motion after-effect (MAE), for example, is an illusory impression of motion after viewing moving displays: subsequently, stationary displays appear to drift in the opposite direction. After-effects have been used extensively in basic vision research and in clinical settings, and are enhanced in migraine.

Enhanced Motion Aftereffects in Migraine Are Related to Contrast Sensitivity: Implications for Models of Differences in Precortical/Cortical Function.

Purpose: Visual tests can be used as noninvasive tools to test models of the pathophysiology underlying neurological conditions, such as migraine. For example, there are reports that the motion aftereffect, which involves neural processing in several cortical areas, is prolonged in migraine. There also are reports of impaired contrast sensitivity in migraine, however, attributed to a precortical dysfunction.

Age- and sex-specific differences in blood-borne microvesicles from apparently healthy humans.

Background: Sex differences in incidence of cardiovascular disease may reflect age-associated intravascular cellular activation resulting in shedding of cell membrane-derived bioactive microvesicles (MV or microparticles) into the blood. Concentrations of cell-specific MV in blood have the potential to be a diagnostic/prognostic marker of pathology, but ranges of MV must first be established in healthy individuals. This study identified cellular origin of blood-borne MV >0.

An inability to exclude visual noise in migraine.

Purpose: People with migraine are relatively poor at judging the direction of motion of coherently moving signal dots when interspersed with noise dots drifting in random directions, a task known as motion coherence. Although this has been taken as evidence of impoverished global pooling of motion signals, it could also arise from unreliable coding of local direction (of each dot), or an inability to segment signal from noise (noise-exclusion). The aim of this study was to determine how these putative limits contribute to impoverished motion processing in migraine.

Color and spatial frequency are related to visual pattern sensitivity in migraine.

Objective: To assess the potential for particular colors to alleviate visual discomfort when people with migraine view repetitive geometric or striped patterns.

Background: Visual stimuli, such as flicker, glare, or stripes, can trigger migraine and headache. They can also elicit feelings of discomfort and aversion.

Motion processing deficits in migraine are related to contrast sensitivity.

Background: There are conflicting reports concerning the ability of people with migraine to detect and discriminate visual motion. Previous studies used different displays and none adequately assessed other parameters that could affect performance, such as those that could indicate precortical dysfunction.

Methods: Motion-direction detection, discrimination and relative motion thresholds were compared from participants with and without migraine.

Visual metacontrast masking in migraine.

Background: In visual metacontrast masking, the visibility of a brief target stimulus can be reduced substantially if it is preceded (forward masking) or followed (backward masking) by a non-overlapping mask. These effects have been attributed to inhibitory processes within the visual system. Two previous studies have used metacontrast masking to assess inhibitory function in migraine and control groups, however, each used different types of masking and obtained different results.

Peri-ictal changes of cortical excitability in children suffering from migraine without aura.

In adult patients with migraine, transcranial magnetic stimulation (TMS) has been used to examine cortical excitability between attacks, but there have been discrepant results. No TMS study has examined cortical excitability in children or adolescents with migraine. Here, we employed TMS to study regional excitability of the occipital (phosphene threshold [PT] and suppression of visual perception) and motor (resting motor threshold and cortical silent period) cortex in ten children suffering from migraine without aura and ten healthy age-matched controls.

Visual pattern adaptation in subjects with photoparoxysmal EEG response: evidence for increased visual cortical excitability.

Purpose: Photosensitivity, or photoparoxysmal response (PPR), is an abnormal EEG reaction to intermittent photic stimulation (IPS), consisting of spikes, spike-waves, and intermittent slow waves. Depending on the spread of the abnormal activity, PPR subgroups have been defined as having either propagating PPR or localized, occipital spikes (OS) only. Recent research suggests an enhanced excitability in the occipital cortex may underlie this reaction during IPS, but it remains unclear whether changes in excitability affect the function of the occipital cortex to other, less provocative visual stimuli.

Dogs catch human yawns.

This study is the first to demonstrate that human yawns are possibly contagious to domestic dogs (Canis familiaris). Twenty-nine dogs observed a human yawning or making control mouth movements. Twenty-one dogs yawned when they observed a human yawning, but control mouth movements did not elicit yawning from any of them.

Orientation discrimination and contrast detection thresholds in migraine for cardinal and oblique angles.

Purpose: To determine whether orientation discrimination deficits in migraine, which have been found to depend on the spatial frequency of the stimulus, are due to precortical dysfunction or to abnormal patterns of orientation tuning at cortical loci. Further, to assess whether any cortical involvement is restricted to the striate cortex or whether higher cortical areas are also involved. Orientation-specific abnormalities would provide evidence of cortical dysfunction.

Spreading photoparoxysmal EEG response is associated with an abnormal cortical excitability pattern.

Photosensitivity or photoparoxysmal response (PPR) is a highly heritable electroencephalographic trait characterized by an abnormal cortical response to intermittent photic stimulation (IPS). In PPR-positive individuals, IPS induces spikes, spike-waves or intermittent slow waves. The PPR may be restricted to posterior visual areas (i.

Transient tritanopia in migraine: evidence for a large-field retinal abnormality in blue-yellow opponent pathways.

Purpose: To determine whether the magnitude of transient tritanopia (TT) differs between migraine and control groups. TT is a retinal phenomenon characterized by a paradoxical reduction in sensitivity to short-wavelength (purple) stimuli after extinction of long-wavelength (yellow) adapting displays. A group difference in the magnitude of TT would provide evidence for a retinal contribution to the S-cone-specific color-processing abnormalities that have been reported in migraine.

Visual stimuli are common triggers of migraine and are associated with pattern glare.

Objective: To investigate the associations between interictal pattern glare, visual stress, and visual triggers of migraine.

Background: There has been relatively little research on the visual stimuli that can trigger migraine episodes. This is surprising, since if practitioners can obviate such triggers, then some attacks may be prevented.

Color vision but not visual attention is altered in migraine.

Objective: To examine visual search performance in migraine and headache-free control groups and to determine whether reports of selective color vision deficits in migraine occur preattentively.

Background: Visual search is a classic technique to measure certain components of visual attention. The technique can be manipulated to measure both preattentive (automatic) and attentive processes.