Migraine in the Young Brain: Adolescents vs. Young Adults.

Migraine is a disease that peaks in late adolescence and early adulthood. The aim of this study was to evaluate age-related brain changes in resting state functional connectivity (rs-FC) in migraineurs vs. age-sex matched healthy controls at two developmental stages: adolescence vs.

In child and adult migraineurs the somatosensory cortex stands out … again: An arterial spin labeling investigation.

Over the past decade, human brain imaging investigations have reported altered regional cerebral blood flow (rCBF) in the interictal phase of migraine. However, there have been conflicting findings across different investigations, making the use of perfusion imaging in migraine pathophysiology more difficult to define. These inconsistencies may reflect technical constraints with traditional perfusion imaging methods such as single-photon emission computed tomography and positron emission tomography.

Anesthesia, brain changes, and behavior: Insights from neural systems biology.

Long-term consequences of anesthetic exposure in humans are not well understood. It is possible that alterations in brain function occur beyond the initial anesthetic administration. Research in children and adults has reported cognitive and/or behavioral changes after surgery and general anesthesia that may be short lived in some patients, while in others, such changes may persist.

EEG frequency tagging using ultra-slow periodic heat stimulation of the skin reveals cortical activity specifically related to C fiber thermonociceptors.

The recording of event-related brain potentials triggered by a transient heat stimulus is used extensively to study nociception and diagnose lesions or dysfunctions of the nociceptive system in humans. However, these responses are related exclusively to the activation of a specific subclass of nociceptive afferents: quickly-adapting thermonociceptors. In fact, except if the activation of Aδ fibers is avoided or if A fibers are blocked, these responses specifically reflect activity triggered by the activation of Type 2 quickly-adapting A fiber mechano-heat nociceptors (AMH-2).

[Transcranial direct current stimulation: new clinical roadmaps for psychiatric research].

Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that has undergone intensive research over the past decade with promising results. tDCS is based on the application of weak, direct current over the scalp, leading to cortical hypo- or hyperpolarization according to the specified parameters. Recent studies have shown that tDCS is able to induce potent changes in cortical excitability as well as to elicit long-lasting modifications in brain activity.

Frequency tagging of steady-state evoked potentials to explore the crossmodal links in spatial attention between vision and touch.

The sustained periodic modulation of a stimulus induces an entrainment of cortical neurons responding to the stimulus, appearing as a steady-state evoked potential (SS-EP) in the EEG frequency spectrum. Here, we used frequency tagging of SS-EPs to study the crossmodal links in spatial attention between touch and vision. We hypothesized that a visual stimulus approaching the left or right hand orients spatial attention toward the approached hand, and thereby enhances the processing of vibrotactile input originating from that hand.

EEG frequency tagging to dissociate the cortical responses to nociceptive and nonnociceptive stimuli.

Whether the cortical processing of nociceptive input relies on the activity of nociceptive-specific neurons or whether it relies on the activity of neurons also involved in processing nonnociceptive sensory input remains a matter of debate. Here, we combined EEG "frequency tagging" of steady-state evoked potentials (SS-EPs) with an intermodal selective attention paradigm to test whether the cortical processing of nociceptive input relies on nociceptive-specific neuronal populations that can be selectively modulated by top-down attention. Trains of nociceptive and vibrotactile stimuli (Experiment 1) and trains of nociceptive and visual stimuli (Experiment 2) were applied concomitantly to the same hand, thus eliciting nociceptive, vibrotactile, and visual SS-EPs.

Steady-state evoked potentials to tag specific components of nociceptive cortical processing.

Studies have shown that the periodic repetition of a stimulus induces, at certain stimulation frequencies, a sustained electro-cortical response of corresponding frequency, referred to as steady-state evoked potential (SSEP). Using infrared laser stimulation, we recently showed that SSEPs can be used to explore nociceptive cortical processing. Here, we implemented a novel approach to elicit such responses, using a periodic intra-epidermal electrical stimulation of cutaneous Aδ-nociceptors (Aδ-SSEPs).

Nociceptive steady-state evoked potentials elicited by rapid periodic thermal stimulation of cutaneous nociceptors.

The periodic presentation of a sensory stimulus induces, at certain frequencies of stimulation, a sustained electroencephalographic response known as steady-state evoked potential (SS-EP). In the somatosensory, visual, and auditory modalities, SS-EPs are considered to constitute an electrophysiological correlate of cortical sensory networks resonating at the frequency of stimulation. In the present study, we describe and characterize, for the first time, SS-EPs elicited by the selective activation of skin nociceptors in humans.