Kyle Mathewson

Research on the neural correlates of consciousness (NCC) has implicated an assortment of brain regions, ERP components, and network properties associated with visual awareness. Recently, the P3b ERP component has emerged as a leading NCC candidate. However, typical P3b paradigms depend on the detection of some stimulus change, making it difficult t...

Oscillatory brain rhythms can bias attention via phase and amplitude changes, which modulate sensory activity, biasing information to be processed or ignored. Alpha band (7-14 Hz) oscillations lateralize with spatial attention and rhythmically inhibit visual activity and awareness through pulses of inhibition. Here we show that human observers' awa...

Theories of brain plasticity propose that, in the absence of input from the preferred sensory modality, some specialized brain areas may be recruited when processing information from other modalities, which may result in improved performance. The Useful Field of View task has previously been used to demonstrate that early deafness positively impact...

Diffuse optical tomography (DOT) provides data about brain function using surface recordings. Despite recent advancements, an unbiased method for estimating the depth of absorption changes and for providing an accurate three-dimensional (3-D) reconstruction remains elusive. DOT involves solving an ill-posed inverse problem, requiring additional cri...

Cell-phone use impairs driving safety and performance. This impairment may stem from the remote partner's lack of awareness about the driving situation. In this study, pairs of participants completed a driving simulator task while conversing naturally in the car and while talking on a hands-free cell phone. In a third condition, the driver drove wh...

Research in stretchable electronics involves fundamental scientific topics relevant to applications with importance in human healthcare. Despite significant progress in active components, routes to mechanically robust construction are lacking. Here, we introduce materials and composite designs for thin, breathable, soft electronics that can adhere...

Mind-wandering, or off-task thought, is believed to be associated with diminished processing of the external sensory environment, while focus is directed at internal dialogue. However, the impact of mind-wandering on driving performance is poorly understood. This study explores the behavioral and EEG oscillatory correlates of mind-wandering while d...

Binocular rivalry occurs when disparate images are shown simultaneously but separately to each eye. Perceptually dominant images reverse over time, with one image temporarily dominating perception while the other is suppressed. Probes presented to the suppressed eye are typically seen by participants and tend to cause perception to shift to the sup...

High-precision retinotopic mapping of the visual field normally uses BOLD signal. Given the divergence between neuronal and hemodynamic responses with aging, however, a more direct measure of neuronal activity is needed to make accurate maps of retinotopic organization. We employed tri-modal neuroimaging of 18-78 year-old subjects using BOLD-fMRI,...

Cellphone use is known to impair driving performance, yet persists. This impairment is thought to stem, in part, from the remote conversation partner's lack of situational awareness. In this study, pairs of participants completed a driving task in a high-fidelity driving simulator while naturally conversing. Similar to previous studies, drivers dro...

We introduce materials and composite designs for thin, breathable, soft electronics that can adhere strongly to the skin. In this protocol, we describe step­by­step procedure of device preparation with helpful information. Procedure Step 1: Preparation of substrate for temporary use in device mounting Timing: 2 hours 1. Prepare a glass slide with t...

Wearable Monitors Advances in microelectronics have yielded high-quality devices that allow for intensive signal collection or transmission. S. Xu et al. (p. 70 ) show how to make a soft wearable system that is constructed like a stretchable circuit board, where the electronic components are bridged electrically by thin, meandering conducting trace...

We investigated the dynamics of brain processes facilitating conscious experience of external stimuli. Previously, we proposed that alpha (8-12 Hz) oscillations, which fluctuate with both sustained and directed attention, represent a pulsed inhibition of ongoing sensory brain activity. Here we tested the prediction that inhibitory alpha oscillation...

We hypothesized that control processes, as measured using electrophysiological (EEG) variables, influence the rate of learning of complex tasks. Specifically, we measured alpha power, event-related spectral perturbations (ERSPs), and event-related brain potentials during early training of the Space Fortress task, and correlated these measures with...

Rhythmic events are common in our sensory world. Temporal regularities could be used to predict the timing of upcoming events, thus facilitating their processing. Indeed, cognitive theories have long posited the existence of internal oscillators whose timing can be entrained to ongoing periodic stimuli in the environment as a mechanism of temporal...

Decision-making in the presence of other competitive intelligent agents is fundamental for social and economic behavior. Such decisions require agents to behave strategically, where in addition to learning about the rewards and punishments available in the environment, they also need to anticipate and respond to actions of others competing for the...

Alpha oscillations have an inhibitory influence on visual processing and fluctuate with both sustained and directed attention. We have proposed a role for these 8–12 Hz oscillations as a pulsed inhibition of ongoing brain activity, given that alpha’s inhibitory influence fluctuates as a function of its phase. An important prediction of this theory...

Alpha oscillations are ubiquitous in the brain, but their role in cortical processing remains a matter of debate. Recently, evidence has begun to accumulate in support of a role for alpha oscillations in attention selection and control. Here we first review evidence that 8-12 Hz oscillations in the brain have a general inhibitory role in cognitive...

Changes in attention allocation with complex task learning reflect processing automatization and more efficient control. We studied these changes using ERP and EEG spectral analyses in subjects playing Space Fortress, a complex video game comprising standard cognitive task components. We hypothesized that training would free up attentional resource...

When viewing ambiguous figures like the classic duck/rabbit, people alternately perceive one interpretation and then the other, but not both interpretations at once. When two identical ambiguous figures appear together, the majority of observers perceive them as identical, and they typically alternate in unison. Just as most observers cannot see a...

It has been proposed that in order for a stimulus to reach consciousness, visual information that is relayed to higher brain areas must also be fed back to the early visual areas for a reverberatory strengthening of the representation. This theory further proposes that when these feedback signals from higher brain areas encounter new activity elici...

We used event-related potentials (ERPs) to study the neural electrical activity associated with conscious perception of targets in a meta-contrast masking paradigm in which the detection of a target is inhibited by a subsequent mask with adjacent but non-overlapping contours. It has been proposed that early visual activity elicited by these stimuli...

At near-threshold levels of stimulation, identical stimulus parameters can result in very different phenomenal experiences. Can we manipulate which stimuli reach consciousness? Here we show that consciousness of otherwise masked stimuli can be experimentally induced by sensory entrainment. We preceded a backward-masked stimulus with a series of rap...

We often fail to see something that at other times is readily detectable. Because the visual stimulus itself is unchanged, this variability in conscious awareness is likely related to changes in the brain. Here we show that the phase of EEG alpha rhythm measured over posterior brain regions can reliably predict both subsequent visual detection and...

Many everyday tasks are complex, involve high levels of cognitive control, and may require extensive learning. The extent of cognitive control exerted may facilitate the learning process. To investigate this hypothesis, we used several indices of cognitive control based on electroencephalographic (EEG) measures recorded while participants played a...

Trials were carried out to investigate the effectiveness of various methods of formaldehyde fumigation as a means of disinfecting calf houses. Houses were cleaned by the farmer, sealed and then fumigated. A significant reduction in bacterial numbers was obtained when the gas was produced by heating paraformaldehyde, mixing formalin with potassium p...

Empirical marketing studies have shown that many types of consumer purchasing behavior can be better explained by taking into account the dynamic learning processes of strategic decision-making. Accordingly, a number of theoretical models of learning have been proposed to demon-strate how different learning strategies can lead to different purchasi...