The Effect of Jittered Stimulus Onset Interval on Electrophysiological Markers of Attention in a Brain-Computer Interface Rapid Serial Visual Presentation Paradigm.

Brain responses to discrete stimuli are modulated when multiple stimuli are presented in sequence. These alterations are especially pronounced when the time course of an evoked response overlaps with responses to subsequent stimuli, such as in a rapid serial visual presentation (RSVP) paradigm used to control a brain-computer interface (BCI). The present study explored whether the measurement or classification of select brain responses during RSVP would improve through application of an established technique for dealing with overlapping stimulus presentations, known as irregular or "jittered" stimulus onset interval (SOI).

Acupuncture-Induced Changes in Nociception, Measured by Pain-Related Evoked Potentials: A Pilot Mechanistic Study.

The nociceptive system has been implicated in acupuncture analgesia, although acupuncture's precise mechanism of action remains unknown. Electric pain-related evoked potentials (PREPs) have emerged as an effective and reliable electrophysiologic method for evaluation of the human nociceptive system by electric stimulation of nociceptive Aδ and C fibers. This pilot mechanistic study aims to assess the feasibility of using advanced PREP techniques together with electroacupuncture and to use PREPs to characterize acupuncture's effect on nociception.

Methodology and preliminary data on feasibility of a neurofeedback protocol to improve visual attention to letters in mild Alzheimer's disease.

Background: Brain-computer interface (BCI) systems are controlled by users through neurophysiological input for a variety of applications, including communication, environmental control, and motor rehabilitation. Although individuals with severe speech and physical impairment are the primary users of this technology, BCIs have emerged as a potential tool for broader populations, including delivering cognitive training/interventions with neurofeedback (NFB).

Methods: This paper describes the development and preliminary testing of a protocol for use of a BCI system with NFB as an intervention for people with mild Alzheimer's disease (AD).

Target-Related Alpha Attenuation in a Brain-Computer Interface Rapid Serial Visual Presentation Calibration.

This study evaluated the feasibility of using occipitoparietal alpha activity to drive target/non-target classification in a brain-computer interface (BCI) for communication. EEG data were collected from 12 participants who completed BCI Rapid Serial Visual Presentation (RSVP) calibrations at two different presentation rates: 1 and 4 Hz. Attention-related changes in posterior alpha activity were compared to two event-related potentials (ERPs): N200 and P300.

SSVEP BCI and Eye Tracking Use by Individuals With Late-Stage ALS and Visual Impairments.

Access to communication is critical for individuals with late-stage amyotrophic lateral sclerosis (ALS) and minimal volitional movement, but they sometimes present with concomitant visual or ocular motility impairments that affect their performance with eye tracking or visual brain-computer interface (BCI) systems. In this study, we explored the use of modified eye tracking and steady state visual evoked potential (SSVEP) BCI, in combination with the Shuffle Speller typing interface, for this population. Two participants with late-stage ALS, visual impairments, and minimal volitional movement completed a single-case experimental research design comparing copy-spelling performance with three different typing systems: (1) commercially available eye tracking communication software, (2) Shuffle Speller with modified eye tracking, and (3) Shuffle Speller with SSVEP BCI.

A single case design to examine short-term intracranial EEG patterns during focused meditation.

Purpose: This study used a multiple crossover ABAB single case design to examine intracranial EEG data during a breath awareness meditation and an active control task.

Results: Visual analyses suggest that a brief breath awareness mediation was consistently associated with increased alpha power when compared to the active control. Less consistent effects were found with theta, beta, and high gamma activity.

Perceived stress mediates the relationship between mindfulness and negative affect variability: A randomized controlled trial among middle-aged to older adults.

Despite the interest in mindfulness over the past 20 years, studies have only recently begun to examine mindfulness in older adults. The primary aim of this study was to evaluate pretreatment to post-treatment change in negative affect variability (NAV) following a mindfulness training among 134 mildly stressed, middle-aged to older adults. The secondary aim was to assess if the effects of mindfulness training on NAV would be partially explained by pretreatment to post-treatment reductions in perceived stress, a trend that would be congruent with several stress models.

Negative Affect Influences Electrophysiological Markers of Visual Working Memory in Mildly Stressed Older Adults.

Negative affect (NA) has been related to lower working memory performance across all ages, including in older adults where it has been suggested as a marker for later cognitive impairments. However, NA-related decreases in working memory performance have not been shown in a full range of working memory paradigms or fully explored in the context of electrophysiological measures of working memory. We examined the impact of NA and related markers on an electroencephalography (EEG) marker of visual working memory (VWM) capacity, referred to as the contralateral delay activity (CDA).

Vigilance state fluctuations and performance using brain-computer interface for communication.

The effect of fatigue and drowsiness on brain-computer interface (BCI) performance was evaluated. 20 healthy participants performed a standardized 11-minute calibration of a Rapid Serial Visual Presentation BCI system five times over two hours. For each calibration, BCI performance was evaluated using area under the receiver operating characteristic curve (AUC).

Effects of simulated visual acuity and ocular motility impairments on SSVEP brain-computer interface performance: An experiment with Shuffle Speller.

Individuals with severe speech and physical impairments may have concomitant visual acuity impairments (VAI) or ocular motility impairments (OMI) impacting visual BCI use. We report on the use of the Shuffle Speller typing interface for an SSVEP BCI copy-spelling task under three conditions: simulated VAI, simulated OMI, and unimpaired vision. To mitigate the effect of visual impairments, we introduce a method that adaptively selects a user-specific trial length to maximize expected information transfer rate (ITR); expected ITR is shown to closely approximate the rate of correct letter selections.