Disengagement Of Visual Attention Research Articles

The unique role of novel linguistic labels on the disengagement of visual attention.

Do novel linguistic labels have privileged access to attentional resources compared to non-linguistic labels? This study explores this possibility through two experiments with a training and an attentional overlap task. Experiment 1 investigates how novel label and object-only stimuli influence resource allocation and disengagement of visual attention. Experiment 2 tests the impact of linguistic information on visual attention by comparing novel tones and labels. Because disengagement of attention is affected both by the salience of the perceptual stimulus and by the degree of familiarity with the stimulus to be disengaged from, we compared pupil size variations and saccade latency under different test conditions: (a) consistent with (i.e., identical to) the training; (b) inconsistent with the training (i.e., with an altered feature), and (c) deprived of one feature only in Experiment 1. Experiment 1 indicated a general consistency advantage (and deprived disadvantage) driven by linguistic label-object pairs compared to object-only stimuli. Experiment 2 revealed that tone-object pairs led to higher pupil dilation and longer saccade latency than linguistic label-object pairs. Our results suggest that novel linguistic labels preferentially impact the early orienting of attention.

The Disengagement of Visual Attention: An Eye-Tracking Study of Cognitive Impairment, Ethnicity and Age.

Various studies have shown that Alzheimer’s disease (AD) is associated with an impairment of inhibitory control, although we do not have a comprehensive understanding of the associated cognitive processes. The ability to engage and disengage attention is a crucial cognitive operation of inhibitory control and can be readily investigated using the “gap effect” in a saccadic eye movement paradigm. In previous work, various demographic factors were confounded; therefore, here, we examine separately the effects of cognitive impairment in Alzheimer’s disease, ethnicity/culture and age. This study included young (N = 44) and old (N = 96) European participants, AD (N = 32), mildly cognitively impaired participants (MCI: N = 47) and South Asian older adults (N = 94). A clear reduction in the mean reaction times was detected in all the participant groups in the gap condition compared to the overlap condition, confirming the effect. Importantly, this effect was also preserved in participants with MCI and AD. A strong effect of age was also evident, revealing a slowing in the disengagement of attention during the natural process of ageing.

The Effects of 10 Hz Transcranial Alternating Current Stimulation on Audiovisual Task Switching.

Neural oscillations in the alpha band (7–13 Hz) are commonly associated with disengagement of visual attention. However, recent studies have also associated alpha with processes of attentional control and stability. We addressed this issue in previous experiments by delivering transcranial alternating current stimulation at 10 Hz over posterior cortex during visual tasks (alpha tACS). As this stimulation can induce reliable increases in EEG alpha power, and given that performance on each of our visual tasks was negatively associated with alpha power, we assumed that alpha tACS would reliably impair visual performance. However, alpha tACS was instead found to prevent both deteriorations and improvements in visual performance that otherwise occurred during sham & 50 Hz tACS. Alpha tACS therefore appeared to exert a stabilizing effect on visual attention. This hypothesis was tested in the current, pre-registered experiment by delivering alpha tACS during a task that required rapid switching of attention between motion, color, and auditory subtasks. We assumed that, if alpha tACS stabilizes visual attention, this stimulation should make it harder for people to switch between visual tasks, but should have little influence on transitions between auditory and visual subtasks. However, in contrast to this prediction, we observed no evidence of impairments in visuovisual vs. audiovisual switching during alpha vs. control tACS. Instead, we observed a trend-level reduction in visuoauditory switching accuracy during alpha tACS. Post-hoc analyses showed no effects of alpha tACS in response time variability, diffusion model parameters, or on performance of repeat trials. EEG analyses also showed no effects of alpha tACS on endogenous or stimulus-evoked alpha power. We discuss possible explanations for these results, as well as their broader implications for current efforts to study the roles of neural oscillations in cognition using tACS.

The disengagement of visual attention in the gap paradigm across adolescence

Attentional disengagement is important for successful interaction with our environment. The efficiency of attentional disengagement is commonly assessed using the gap paradigm. There is, however, a sharp contrast between the number of studies applying the gap paradigm to clinical populations and the knowledge about the underlying developmental trajectory of the gap effect. The aim of the present study was, therefore, to investigate attentional disengagement in a group of children aged 9–15. Besides the typically deployed gap and the overlap conditions, we also added a baseline condition in which the fixation point was removed at the moment that the target appeared. This allowed us to reveal the appropriate experimental conditions to unravel possible developmental differences. Correlational analyses showed that the size of the gap effect became smaller with increasing age, but only for the difference between the gap and the overlap conditions. This shows that there is a gradual increase in the capacity to disengage visual attention with increasing age, but that this effect only becomes apparent when the gap and the overlap conditions are compared. The gradual decrease of the gap effect with increasing age provides additional evidence that the attentional system becomes more efficient with increasing age and that this is a gradual process.

Disengagement of Visual Attention in Infancy is Associated with Emerging Autism in Toddlerhood

BackgroundEarly emerging characteristics of visual orienting have been associated with a wide range of typical and atypical developmental outcomes. In the current study, we examined the development of visual disengagement in infants at risk for autism.MethodsWe measured the efficiency of disengaging from a central visual stimulus to orient to a peripheral one in a cohort of 104 infants with and without familial risk for autism by virtue of having an older sibling with autism.ResultsAt 7 months of age, disengagement was not robustly associated with later diagnostic outcomes. However, by 14 months, longer latencies to disengage in the subset of the risk group later diagnosed with autism was observed relative to other infants at risk and the low-risk control group. Moreover, between 7 months and 14 months, infants who were later diagnosed with autism at 36 months showed no consistent increases in the speed and flexibility of visual orienting. However, the latter developmental effect also characterized those infants who exhibited some form of developmental concerns (but not meeting criteria for autism) at 36 months.ConclusionsInfants who develop autism or other developmental concerns show atypicality in the development of visual attention skills from the first year of life.

Determinants of attentional modulation near the hands

A series of visual search experiments conducted by Abrams et al. (2008) indicates that disengagement of visual attention is slowed when the array of objects that are to be searched are close to the hands (hands on the monitor) than if they are not close to the hands (hands in the lap). These experiments establish the impact one's hands can have on visual attentional processing. In the current paper we more closely examine these two hand postures with the goal of pinpointing which characteristics are crucial for the observed differences in attentional processing. Specifically, in a set of 4 experiments we investigated additional hand postures and additional modes of response to address this goal. We replicated the original Abrams et al. (2008) effect when only the two original postures were used; however, surprisingly, the effect was extinguished with the new range of postures and response modes, and this extinction persisted across different populations (German and English students), and different experimental hardware. Furthermore, analyses indicated that it is unlikely that the extinction of the effect was caused by increased practice due to additional blocks of trials or by an increased probability that participants were able to guess the purpose of the experiment. As such our results suggest that in addition to the nature of the postures of the hand, the number of postures is a further important factor that influences the impact the hands have on visual processing.

Disengagement of Visual Attention in Infancy is Associated with Emerging Autism in Toddlerhood

Disengagement of Visual Attention in Infancy is Associated with Emerging Autism in Toddlerhood

Presaccadic attention allocation and express saccades.

Express saccades are visually-guided saccades that are characterized by an extremely short latency of about 100 ms. The present experiments tested the hypothesis that a disengagement of visual attention is necessary for the generation of express saccades. All subjects produced large numbers of express saccades in the gap paradigm, in which the fixation stimulus is removed 200 ms before target onset (Exp. 1), but not in the overlap paradigm, in which the fixation stimulus remained on during the entire trial (Exp. 2). By means of peripheral cues (Exps. 3-5) and central cues (Exps. 6-7), visual attention was directed at the target location for the saccade before the actual appearance of the saccade target. In all experiments, the location cues facilitated rather than abolished express saccades. The generation of express saccades was facilitated even when the currently fixated visual stimulus was not removed before target onset (fixation-overlap; Exps. 5-7). The results are explained by the hypothesis that a disengagement of a separate fixation system is necessary for the generation of express saccades, a hypothesis that is in line with current neurobiological findings.

Asymmetries in the covert orienting of visual spatial attention in schizophrenia

The presence of attentional asymmetries in patients with schizophrenia was investigated with particular emphasis on the effects of stage of disease, medication status and clinical symptom severity. A modified version of Posner's covert orienting of visual attention task (COVAT) which included both spatial and non-spatial cues was administered to six volunteer samples of subjects which consisted of (i) 15 unmedicated and acutely psychotic male subjects with schizophrenia, (ii) 15 male subjects with schizophrenia who had been receiving medication for 14–21 days, (iii) 10 chronic male schizophrenic subjects who had been receiving medication for at least two years, (iv) 10 acutely psychotic male subjects with non-schizophrenic psychoses, (v) 15 subjects with unilateral brain frontal lobe ( n = 6) or parietal lobe ( n = 9) lesions, (vi) and 15 male control subjects. Measures of saccadic and pursuit eye movements were also obtained from unmedicated and recently medicated subjects with schizophrenia. COVAT attentional asymmetries were present in unmedicated subjects with schizophrenia for the 150 msec stimulus onset asynchrony (SOA). These asymmetries arose because reaction times (RTs) to right visual field targets were significantly slower than RTs to left visual field targets when targets followed invalid spatial or non-spatial cues. These asymmetries were qualitatively similar to those found in the patients with unilateral parietal lobe lesions. Attentional asymmetries partially resolved with brief periods of medication and completely resolved with long periods of medication. No asymmetries were found in controls nor in unmedicated subjects without schizophrenia. No asymmetries of ocular motor function were found. In schizophrenia, attentional asymmetries may reflect a deficit in the disengagement of visual attention from the right visual field and appear to be a stage marker for the disease. However this attentional deficit is dynamic and may reflect disruption to the neurocognitive network controlling attention at the level of the anterior cingulate cortex.