Hyperfocusing of attention on goal-related information in schizophrenia: Evidence from electrophysiology.

Schizophrenia clearly involves impairments of attention, but the precise nature of these impairments has been difficult to determine. One possibility is that the deficit in attention is a secondary consequence of a deficit in goal maintenance. However, recent research suggests that people with schizophrenia (PSZ) actually focus attention more strongly on objects containing goal-relevant features.

How Attention Changes in Response to Incentives.

Although the performance of simple cognitive tasks can be enhanced if an incentive is provided, the mechanisms enabling such motivational control are not known. This study sought to uncover how mechanisms of attention and readiness are altered by reward-associated incentive stimuli. We measured EEG/ERP activity as human adults viewed a high- or low-incentive cue, experienced a short preparation interval, and then performed a simple visual search task to gain the predicted reward.

Effective connectivity during feature-based attentional capture: evidence against the attentional reorienting hypothesis of TPJ.

The most prevalent neurobiological theory of attentional control posits 2 distinct brain networks: The dorsal and ventral attention networks. The role of the dorsal attentional network in top-down attentional control is well established, but there is less evidence for the putative role of the ventral attentional network in initiating stimulus-driven reorienting. Here, we used functional magnetic resonance imaging and dynamic causal modeling (DCM) to test the role of the ventral and dorsal networks in attentional reorienting during instances of attentional capture by a target-colored distracter.

Active suppression after involuntary capture of attention.

After attention has been involuntarily captured by a distractor, how is it reoriented toward a target? One possibility is that attention to the distractor passively fades over time, allowing the target to become attended. Another possibility is that the captured location is actively suppressed so that attention can be directed toward the target location. The present study investigated this issue with event-related potentials (ERPs), focusing on the N2pc component (a neural measure of attentional deployment) and the Pd component (a neural measure of attentional suppression).

A common neural mechanism for preventing and terminating the allocation of attention.

Much is known about the mechanisms by which attention is focused to facilitate perception, but little is known about what happens to attention after perception of the attended object is complete. One possibility is that the focus of attention passively fades. A second possibility is that attention is actively terminated after the completion of perception so that the brain can be prepared for the next target.

Active suppression of distractors that match the contents of visual working memory.

The biased competition theory proposes that items matching the contents of visual working memory will automatically have an advantage in the competition for attention. However, evidence for an automatic effect has been mixed, perhaps because the memory-driven attentional bias can be overcome by top-down suppression. To test this hypothesis, the Pd component of the event-related potential waveform was used as a marker of attentional suppression.

Capture versus suppression of attention by salient singletons: electrophysiological evidence for an automatic attend-to-me signal.

There is considerable controversy about whether salient singletons capture attention in a bottom-up fashion, irrespective of top-down control settings. One possibility is that salient singletons always generate an attention capture signal, but this signal can be actively suppressed to avoid capture. In the present study, we investigated this issue by using event-related potential recordings, focusing on N2pc (N2-posterior-contralateral; a measure of attentional deployment) and Pd (distractor positivity; a measure of attentional suppression).

Top-down directed attention to stimulus features and attentional allocation to bottom-up deviations.

One highly controversial issue with respect to visual selective attention concerns the degree to which the top-down attentional mechanism modulates attentional allocation to bottom-up deviation. We investigated whether top-down directed attention to a stimulus feature modulates attentional allocation to task-irrelevant, bottom-up deviation. The P3 event-related potential was measured as an electrophysiological marker of attentional allocation.

Difficulty of discrimination modulates attentional capture by regulating attentional focus.

Attentional capture for distractors is enhanced by increasing the difficulty of discrimination between the standard and the target in the three-stimulus oddball paradigm. In this study, we investigated the cognitive mechanism of this modulation of attentional capture. Event-related brain potentials were recorded from participants while they performed a visual three-stimulus oddball paradigm (frequent standard, rare target, and rare distractor).

Distractor P3 is associated with attentional capture by stimulus deviance.

Objective: A simple distractor elicits a large P3 when the standard and target are difficult to discriminate in the three-stimulus oddball paradigm. This study investigated whether the distractor P3 reflects attentional capture by stimulus deviance or cognitive interference with maintaining the standard representation.

Methods: Event-related brain potentials were recorded from 12 participants who performed a visual three-stimulus oddball paradigm.

Difficulty of discrimination modulates attentional capture for deviant information.

It has been reported that an increased difficulty of discrimination between standard and target enhances P3a for typical nontarget. To elucidate the mechanism of this effect on deviant processing, the P300 event-related brain potential (ERP) was elicited using a visual three-stimulus oddball paradigm (standard circle, .70, target circle, .

Stimulus context determines whether non-target stimuli are processed as task-relevant or distractor information.

Objective: The P300 event-related brain potential (ERP) was elicited using a visual three-stimulus oddball paradigm (standard 0.70, target 0.15, non-target 0.

Severity of AD/HD symptoms and efficiency of attentional resource allocation.

This study investigated the mechanism that underlies the inefficient allocation of attentional resources in Attention-Deficit/Hyperactivity Disorder (AD/HD). The P300 event-related brain potential (ERP) was elicited from 24 healthy adults using a visual three-stimulus oddball paradigm (standard, 70%; target, 15%; non-target, 15%) and the degree of their AD/HD symptoms was assessed by using AD/HD symptom scales. Target stimulus was a circle and standard stimulus was an "X".