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Background and objective People with migraine headache have altered interictal visual sensory-level processing in between headache attacks. Here we examined the extent to which these migraine abnormalities may extend into higher visual processing such as implicit evaluative analysis of visual images in between migraine events. Methods Specifically, we asked two groups of participants––migraineurs ( N =29) and non-migraine controls ( N =29)––to view a set of unfamiliar commercial logos in the context of a target identification task as the brain electrical responses to these objects were recorded via event-related potentials (ERPs). Following this task, participants individually identified those logos that they most liked or disliked. We applied a between-groups comparison of how ERP responses to logos varied as a function of hedonic evaluation. Results Our results suggest migraineurs have abnormal implicit evaluative processing of visual stimuli. Specifically, migraineurs lacked a bias for disliked logos found in control subjects, as measured via a late positive potential (LPP) ERP component. Conclusions These results suggest post-sensory consequences of migraine in between headache events, specifically abnormal cognitive evaluative processing with a lack of normal categorical hedonic evaluation. [ABSTRACT FROM AUTHOR]

Abstract: The pathophysiology of migraine includes a heightened excitability of visual cortex that persists between headache events and that has been linked to impaired inhibitory intracortical processes. Here we examined the hypothesis that this cortical pathophysiology would affect the top–down attentional control of visual cortex. We asked two groups of participants—migraineurs (N =29) and non-migraine controls (N =29)—to perform a probabilistic spatial orienting task as we measured visual sensory cortical responses via event-related potentials (ERPs). Data were then analyzed as a function of whether the ERP-eliciting stimulus was in the fovea vs. parafovea, and whether the stimulus’ location was attended or unattended. In this regard, we found two key between-groups differences in the effect of attention on sensory-evoked visual-cortical activity. First, relative to controls, migraineurs showed a larger attention effect in the visual N1 ERP component for events at the fovea. Second, unlike controls, migraineurs showed no early-phase attention effect in the P1 ERP component for events in the parafovea. Despite these altered ERP responses in migraineurs, however, corresponding behavioral data indicated that they also had heightened response performance. Taken together, our results support the hypothesis that migraineurs have an altered top–down attentional control of visual cortex, with the data suggesting that the effect may be tied to a reduced ability to suppress sensory-evoked activity for unattended events in the visual periphery. [Copyright &y& Elsevier]

• Explicitly defined unique , shared , and dominant fMRI brain activation • Used familiar regular and exception words (and pictures) to force lexical reading • When visual complexity is controlled, some dominant LOC activation for pictures • Shared activation in VWFA and LOC for both reading and picture identification • Challenges overly specialized models of reading or picture naming Identifying printed words and pictures concurrently is ubiquitous in daily tasks, and so it is important to consider the extent to which reading words and naming pictures may share a cognitive-neurophysiological functional architecture. Two functional magnetic resonance imaging (fMRI) experiments examined whether reading along the left ventral occipitotemporal region (vOT; often referred to as a visual word form area, VWFA) has activation that is overlapping with referent pictures (i.e., both conditions significant and shared , or with one significantly more dominant) or unique (i.e., one condition significant, the other not), and whether picture naming along the right lateral occipital complex (LOC) has overlapping or unique activation relative to referent words. Experiment 1 used familiar regular and exception words (to force lexical reading) and their corresponding pictures in separate naming blocks, and showed dominant activation for pictures in the LOC, and shared activation in the VWFA for exception words and their corresponding pictures (regular words did not elicit significant VWFA activation). Experiment 2 controlled for visual complexity by superimposing the words and pictures and instructing participants to either name the word or the picture, and showed primarily shared activation in the VWFA and LOC regions for both word reading and picture naming, with some dominant activation for pictures in the LOC. Overall, these results highlight the importance of including exception words to force lexical reading when comparing to picture naming, and the significant shared activation in VWFA and LOC serves to challenge specialized models of reading or picture naming. [ABSTRACT FROM AUTHOR]

Background We report the case of a 40-year-old patient with a large, World Health Organization grade III oligodendroglioma in the left parietal lobe. Case Description Presurgical planning included functional magnetic resonance imaging (fMRI) localization of language, motor, and somatosensory processing. fMRI results for motor and somatosensory tasks revealed activation in perilesional regions near the surgical resection as well as deactivation in the tumor for the sensory task, suggesting decreased autoregulation in the region owing to the glioma. fMRI results showed left-hemisphere dominance for language and activation in perilesional regions for all 3 speech tasks (i.e., word reading, picture naming, and semantic questions). In addition, the results demonstrated that the high vascularity of the lesion altered the blood oxygen level–dependent function, resulting in false-positive and false-negative activation in the semantic questions and leg/foot rubbing task, respectively. Intraoperative direct cortical stimulation was conducted in the regions corresponding to fMRI activation while the patient performed motor, sensory, and language tasks and showed no loss of function. Follow-up fMRI revealed that there was no longer activation in the tumor or in perilesional regions, presumably owing to the resection of the vascularized tumor. Conclusions This case highlights the importance of presurgical fMRI to inform the neurosurgical approach and emphasizes the need for careful interpretation of fMRI data, especially in cases of malignant glioma, which can decrease autoregulation in surrounding regions, affecting fMRI blood oxygen level–dependent signal. [ABSTRACT FROM AUTHOR]