Changes In Selective Attention Research Articles

Negative BOLD signal changes in ipsilateral primary somatosensory cortex are associated with perfusion decreases and behavioral evidence for functional inhibition

We used functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) to study the negative blood oxygenation level dependent (BOLD) signal and its underlying blood flow changes in healthy human subjects. This was combined with psychophysiological measurements to test that the negative BOLD signal is associated with functional inhibition. Electrical stimulation of the median nerve at 7 Hz evoked robust negative BOLD signals in the primary somatosensory cortex (SI) ipsilateral to stimulation, and positive BOLD signals in contralateral SI. The negative BOLD signal in ipsilateral SI was accompanied by commensurate decreases in relative regional cerebral blood flow (rCBF). Conjunction analysis of the fMRI and PET data revealed a region in the ipsilateral postcentral gyrus showing overlap of negative BOLD signals and relative rCBF decreases. The current perception threshold (CPT) at the ipsilateral finger during concomitant stimulation of the contralateral median nerve increased significantly, suggesting augmented functional inhibition. Since the CPT in the ipsilateral hallux did not significantly change in response to median nerve stimulation, it is more likely that the CPT-increase for the finger is due to functional inhibition (Kastrup et al., 2008) than to changes in selective attention. In conclusion, our data provide evidence that stimulus-induced reductions in relative rCBF may underlie the negative BOLD signal, which in turn may reflect increments in functional inhibition.

Age-related differences in warning symbol comprehension and training effectiveness: effects of familiarity, complexity, and comprehensibility

Age-related changes in selective attention, inhibitory efficiency, and the ability to form new associations suggest that older adults may have greater difficulty with more complex and less comprehensible symbols. We examined comprehension of symbols varying in terms of ratings of familiarity, complexity, and comprehensibility, by younger (aged 18–35) and older (aged 55–70) adults. It was found that older adults have greater difficulty than younger adults in comprehending warning symbols and that accident scenario training improves comprehension. Regression analyses indicated that familiarity and comprehensibility were important in determining performance on the pre-training comprehension test by both younger and older adults. However, training eliminated the effects of stimulus characteristics for younger adults, while older adults' comprehension continued to be significantly influenced by comprehensibility. We suggest that symbol design incorporates cues to knowledge to facilitate the linkage between new knowledge (i.e. the warning symbol) and relevant knowledge in long-term memory. Statement of Relevance: Symbol characteristics play an important role in age-related differences in warning symbol comprehension. To optimise comprehension by older adults, symbols should have a clear relationship with areal-world referent. Alternatively, symbol design could incorporate cues to knowledge to facilitate the linkage between new knowledge and relevant knowledge in long-term memory.

Stroop Effects in Persons with Traumatic Brain Injury: Selective Attention, Speed of Processing, or Color-Naming? A Meta-analysis

The color word Stroop test is the most common tool used to assess selective attention in persons with traumatic brain injury (TBI). A larger Stroop effect for TBI patients, as compared to controls, is generally interpreted as reflecting a decrease in selective attention. Alternatively, it has been suggested that this increase in Stroop effects is influenced by group differences in generalized speed of processing (SOP). The current study describes an overview and meta-analysis of 10 studies, where persons with TBI (N = 324) were compared to matched controls (N = 501) on the Stroop task. The findings confirmed that Stroop interference was significantly larger for TBI groups (p = .008). However, these differences may be strongly biased by TBI-related slowdown in generalized SOP (r² = .81 in a Brinley analysis). We also found that TBI-related changes in sensory processing may affect group differences. Mainly, a TBI-related increase in the latency difference between reading and naming the font color of a color-neutral word (r² = .96) was linked to Stroop effects. Our results suggest that, in using Stroop, it seems prudent to control for both sensory factors and SOP to differentiate potential changes in selective attention from other changes following TBI.

The role of sensory modality in age-related distraction: A critical review and a renewed view.

Selective attention requires the ability to focus on relevant information and to ignore irrelevant information. The ability to inhibit irrelevant information has been proposed to be the main source of age-related cognitive change (e.g., Hasher & Zacks, 1988). Although age-related distraction by irrelevant information has been extensively demonstrated in the visual modality, studies involving auditory and cross-modal paradigms have revealed a mixed pattern of results. A comparative evaluation of these paradigms according to sensory modality suggests a twofold trend: Age-related distraction is more likely (a) in unimodal than in cross-modal paradigms and (b) when irrelevant information is presented in the visual modality, rather than in the auditory modality. This distinct pattern of age-related changes in selective attention may be linked to the reliance of the visual and auditory modalities on different filtering mechanisms. Distractors presented through the auditory modality can be filtered at both central and peripheral neurocognitive levels. In contrast, distractors presented through the visual modality are primarily suppressed at more central levels of processing, which may be more vulnerable to aging. We propose the hypothesis that age-related distractibility is modality dependent, a notion that might need to be incorporated in current theories of cognitive aging. Ultimately, this might lead to a more accurate account for the mixed pattern of impaired and preserved selective attention found in advancing age.

CBT for childhood anxiety disorders: differential changes in selective attention between treatment responders and non‐responders

This study examined whether treatment response to stepped-care cognitive-behavioural treatment (CBT) is associated with changes in threat-related selective attention and its specific components in a large clinical sample of anxiety-disordered children. Ninety-one children with an anxiety disorder were included in the present study. Children received a standardized stepped-care CBT. Three treatment response groups were distinguished: initial responders (anxiety disorder free after phase one: child-focused CBT), secondary responders (anxiety disorder free after phase two: child-parent-focused CBT), and treatment non-responders. Treatment response was determined using a semi-structured clinical interview. Children performed a pictorial dot-probe task before and after stepped-care CBT (i.e., before phase one and after phase two CBT). Changes in selective attention to severely threatening pictures, but not to mildly threatening pictures, were significantly associated with treatment success. At pre-treatment assessment, initial responders selectively attended away from severely threatening pictures, whereas secondary responders selectively attended toward severely threatening pictures. After stepped-care CBT, initial and secondary responders did not show any selectivity in the attentional processing of severely threatening pictures. Treatment non-responders did not show any changes in selective attention due to CBT. Initial and secondary treatment responders showed a reduction of their predisposition to selectively attend away or toward severely threatening pictures, respectively. Treatment non-responders did not show any changes in selective attention. The pictorial dot-probe task can be considered a potentially valuable tool in assigning children to appropriate treatment formats as well as for monitoring changes in selective attention during the course of CBT.

Why a neuromaturational model of memory fails: exuberant learning in early infancy.

The characteristics of memory in infants and adults seem vastly different. The neuromaturational model attributes these differences to an ontogenetic change in the basic memory process, namely, to the hierarchical maturation of two distinct memory systems. The early-maturing (implicit) system is functional during the first third of infancy and supports the gradual learning of perceptual and motor skills; the late-maturing (explicit) system supports representations of contextually specific events, relationships, and associations. An alternative model holds that the basic memory process does not change, but what infants and adults select to encode for learning does. This ontogenetic change in selective attention has been mistaken for an ontogenetic shift in the basic memory process. Over the last 25 years, evidence from transfer studies with developing rats and human infants has revealed that the first third of infancy is actually a period of exuberant learning that ends, not coincidentally, at the same age that the late-maturing memory system presumably emerges. This article reviews data from recent studies of sensory preconditioning, potentiation, associative chains, and transitive inference with human infants that support this conclusion-data for which the neuromaturational model cannot account. Fast mapping is a general learning mechanism that accounts for this evidence.

Sleep deprivation and its effects on object-selective attention

Sleep deprivation (SD) affects attention but it is an open question as to whether all subtypes of attention are similarly affected. We investigated the effects of 24 h of total SD on object-selective attention. 26 healthy, young adults viewed quartets of alternating faces or place scenes and performed selective judgments on faces only, scenes only or both faces and scenes. Volunteers underwent fMRI following a normal night of sleep and again following approximately 24 h of total sleep deprivation in a counterbalanced fashion. Sleep deprivation resulted in slower and less accurate picture classification as well as poorer recognition memory for scenes. Attention strongly modulated activation in the Parahippocampal Place Area (PPA). Task-related activation in the fronto-parietal cortex and PPA was reduced in SD, but the relative modulation of PPA activation by attention was preserved. Psychophysiological interaction between the left intra-parietal sulcus and the PPA that was clearly present after a normal night of sleep was reduced below threshold following SD suggesting that PPI may be a more sensitive method of detecting change in selective attention. Sleep deprivation may affect object-selective attention in addition to exerting a task-independent deficit in attention.

Selective attention and perceptual learning of speech

Phonetic experience can change the perceptual distance between speech sounds, increasing both within-category similarity and between-category distinctiveness. Such warping of perceptual space is frequently characterized in terms of changes in selective attention: Listeners are assumed to attend more strongly to category-differentiating features while ignoring less relevant ones. However, the link between the distribution of selective attention and categorization-related differences in perceptual distance has not been empirically demonstrated. To explore this relationship, listeners were given 6 h of training to categorize sounds according to one of two acoustic features while ignoring the other. The features were voice onset time and onset f0, which are normally correlated and can both serve as a cue to consonant voicing. Before and after training, listener’s performance on a Garner selective attention task was compared with assessment of the perceptual distance between tokens. Results suggest that training can induce both warping of perceptual space and changes in the distribution of selective attention, but the two phenomena are not necessarily related. Results are consistent with a two-stage model of perceptual learning, involving both preattentive adjustment of acoustic cue weighting and higher-level changes in the distribution of selective attention between acoustic cues. [Work supported by NIH-NIDCD 1R03DC006811.]

A developmental change in selective attention and global form perception

The primary purpose of the present study was to examine the processing of local and global perception in relation to selective attention during development from childhood to early adulthood. Filtering was the specific component of selective attention that was examined. The influence of varying distractor congruency and compatibility on relative local-global processing was also examined. Distractor congruency and compatibility did not differentially affect local and global processing. With the presence of neutral distractors, however, 6- and 8-year-old participants demonstrated a greater increase in RTs for global targets relative to local targets whereas older children and adults showed the same pattern of RTs for both local and global targets. The results are suggestive of separate developmental trajectories for global and local level processes, with global processing undergoing developmental change at least until 8 years of age.

Age-related changes in selective attention and perceptual load during visual search.

Three visual search experiments were conducted to test the hypothesis that age differences in selective attention vary as a function of perceptual load (E. A. Maylor & N. Lavie, 1998). Under resource-limited conditions (Experiments 1 and 2), the distraction from irrelevant display items generally decreased as display size (perceptual load) increased. This perceptual load effect was similar for younger and older adults, contrary to the findings of Maylor and Lavie. Distraction at low perceptual loads appeared to reflect both general and specific inhibitory mechanisms. Under more data-limited conditions (Experiment 3), an age-related decline in selective attention was evident, but the age difference was not attributable to capacity limitations as predicted by the perceptual load theory.

Sources of Interference from Irrelevant Information: A Developmental Study

The present study investigated the mechanisms underlying reductions in the susceptibility to interference from irrelevant information that are evident in the developing child. In the first experiment, where the task was to focus on one stimulus dimension and to ignore a second dimension, variations in the degree of spatial integration in multidimensional stimulus configurations did not influence interference effects. Developmental trends in selective attention could not be attributed to age changes in the accessibility of dimensional structure. The second experiment, where the task was to focus on a central arrow stimulus and to ignore flanking arrows, allowed further examination of the mechanisms involved in developmental changes in interference effects. The primary source of the developmental decrease in interference from irrelevant information was found to be in the rate at which the output of perceptual analysis is coupled to the preparation and execution of a motor response, rather than in perceptual filtering or in response preparation. The combined results suggest that age changes in selective attention are mediated to an important extent by changes in the speed and efficiency of stimulus–response translation processes. These findings are discussed in terms of developmental theories of interference control.

Lexical Priming by Pictures and Words in Normal Aging and in Dementia of the Alzheimer's Type

Alzheimer's disease causes a progressive loss of semantic memory, one manifestation of which is a progressive language deficit. In order to delineate the relationship between cognitive processing deficits and language disturbance, word–word and picture–word lexical-decision priming tasks were administered to patients with mild dementia of the Alzheimer's type (DAT) (n = 6), very mild DATs (n = 7), and older normals (n = 23). The mild DATs differed from the other two groups in both tasks. When pictures were used as primes, significant identity priming was seen in the normals and very mild DATs, but not in the mild DATs. The mild DATs showed an aberrant pattern—responses significantly slower with picture primes than with nonsense primes in all three picture–word conditions. This may reflect residual inhibitory activity within a damaged associational network. In the word–word paradigm, the mild DAT subjects demonstrated significant priming both when the prime and target were identical (identity priming, e.g.,dog–dog) and when they were semantically related (semantic priming, e.g.,cat–dog). The other two groups showed no significant priming. These data reinforce other studies which have found that DAT subjects show a supranormal amount of word–word lexical-decision priming. This “hyperpriming” may occur due to partially degraded internal representations which benefit from priming more than intact representations (a cognitive crutch). Both paradigms thus exposed information-processing deficits which distinguished mild DATs from the other two groups. DAT-induced changes in selective attention are probably contributing to these results.

Changes in selective attention as measured by the visual averaged evoked potential following REM deprivation in man

After rapid eye movement (REM) and non-REM deprivation, the amplitude of the major component of the averaged evoked potential (AEP) in attention and non-attention conditions was measured. The difference between the AEP in the attention and the non-attention conditions is considered to be a measure of selective attention and is greater following REM deprivation. It is suggested that this narrowing of the attentive field may be due to increased arousal or greater central nervous system excitability following REM deprivation.

CHILDREN'S SELECTIVE ATTENTION TO STIMULI: STAGE OR SET?

GAINES, ROSSLYN. Children's Selective Attention to Stimuli: Stage or Set? CHILD DEVELOPMENT, 1970, 41, 979-991. The reliability of young children's selective attention to color and form dimensions was measured among two S types:-color and form selector Ss were assigned either to experimental training (on a dimension different than their dominant selection), to same training on their dominant choice dimension, or a no-training control group. Trained Ss had either hard or easy discrimination training over a 5-week period. The results indicate significant changes in selective attention among both color and form selectors given hard training and among color selectors given easy training. Form selectors given easy training showed change trends in the appropriate direction. Control color and form Ss show no significant changes in selection. The results show selective attention to color or form can be experimentally changed and is not developmentally determined for all Ss. Other sources of attention to color and form dimensions are discussed.

The effect of alcohol and noise on components of a tracking and monitoring task.

Recent findings in stress research indicate the necessity for examining the distribution of the operator's attention in complex tasks as well as his information transmission capabilities. This study examines the effects of alcohol and noise on a complex tracking and signal‐detection task with particular reference to changes in selective attention. The operator was instructed to give the tracking task priority. In noise tracking performance improved, but detection of lights placed on the periphery of vision was degraded. Alcohol had the same effect on peripheral detection, but tracking performance fell. It was concluded that the effect of alcohol on such simulated driving skills embodied two factors: the first an increase in attentional bias towards the high priority regions of the visual field, and the second a decrease in the information transmission rate. Since from the point of view of the tracking task these factors are mutually antagonistic, there may be an offsetting of the loss in transmission rate by more optimal dispositions of attention. The loss of peripheral awareness in this event is inevitable, and even at the low alcohol levels used was of apparently serious proportions.