Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ATTENTION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Immediate effects of methylphenidate on cognitive attention skills of children with attention-deficit-hyperactivity disorder.

This study investigated the immediate effects of stimulant medication (methylphenidate) on cognitive attention processes in children with attention-deficit-hyperactivity disorder (ADHD). Thirteen males and two females (mean age 9 y 5 mo, SD 18.3 mo) with a diagnosis of ADHD and who were to be prescribed methylphenidate were assessed twice on one day with the Test of Everyday Attention for Children, a neuropsychological battery designed to tap different aspects of cognitive attention. Between assessments, the children were administered methylphenidate (10 mg). Each child had at least average intelligence (IQ 80 or over, as measured by the Wechsler Intelligence Scale for Children-III UK) and was on no other medication. A group of 16 children, who were matched for age, sex, and intelligence, also performed the cognitive tests twice on the same day to control for practice effects of testing. At the first assessment, children with ADHD demonstrated significant impairments in several aspects of cognitive attention in comparison with the control group, particularly sustained attention. After administration of methylphenidate for the children with ADHD, they showed significant improvements in their performance on measures of cognitive attention compared to controls. The immediate effects of methylphenidate and the significance of measuring cognitive aspects of attention as well as behavioural measures are discussed.

Attention↗

Movement-attention coupling in infancy and attention problems in childhood.

Adaptive behavior requires the integration of body movement and attention. Therefore, individual differences in integration of movement and attention during infancy may have significance for development. We contacted families whose 8-year-old children (n=26; 16 females, 10 males; mean age 8 y 2 mo, SD 8 mo) participated in a previous study of movement-attention coupling at 1 or 3 months of age, to assess parent-reported attention or hyperactivity problems using the Child Behavior Checklist and Diagnostic and Statistical Manual of Mental Disorders (4th edn) criteria. Parent-reported attention problems at 8 years of age were associated with less suppression of body movement at onset of looking, and greater rebound of body movement following its initial suppression at 3 months, but not at 1 month. Parent-reported hyperactivity was not related to any of the infant movement-attention measures. Results suggests that the dynamic integration of movement and attention early in life may have functional significance for the development of attention problems in childhood.

Adaptation, Psychological↗

Asymmetrical hemispheric control of visual-spatial attention in adults with attention deficit hyperactivity disorder.

As neuropsychological mechanisms for attention have been hypothesized to be located in the right hemisphere of the brain, several investigators have begun to conceptualize attention deficit hyperactivity disorder (ADHD)-related attentional deficits as involving right-hemispheric abnormalities. The authors evaluated and compared adult patients diagnosed with ADHD with a non-ADHD group of patients using a chronometric visual-spatial attention task that is sensitive to hemispheric differences in efficiency of information processing. Reaction times across different cuing conditions, cue-target delays, and visual fields were assessed. When participants' attention was misdirected with cues in the right visual field and attention had to be switched to a target on the left visual field, there was a longer delay among ADHD adults than non-ADHD adults, specifically when the interval between the cue and target was 800 ms as compared with 100 ms. This specific pattern of dysfunction was interpreted as a difficulty with maintaining attention possibly associated with anterior attention mechanisms in the right hemisphere.

Adolescent↗

Attention patterns in children with attention deficit disorder with or without hyperactivity.

The objective of this study was to differentiate the attention patterns associated with attention deficit disorder with or without hyperactivity using continuous performance test (CPT). The diagnoses were based on the DSM-III, III-R, and IV criteria and of the 39 children who participated in the study, 14 had attention deficit disorder with hyperactivity (ADDH) and 11 had attention deficit disorder without hyperactivity (ADDWO), while 14 normal children served as a control group. Attention patterns were examined according to the performance of subjects on the CPT and parental scores on the ADHD Rating Scale, the Child Attention Profile, and the Conners Rating Scale. CPT performances were assessed before and after administration of 10 mg methylphenidate. We found as hypothesized that the CPT differentiated between the ADDH and ADDWO groups. However, contrary to our expectations, the ADDH children made more omission errors than the ADDWO children; they also showed more hyperactivity and impulsivity. The performance of both groups improved to an equal degree after the administration of methylphenidate. It is concluded that different subtypes of the attention deficit disorders are characterized by different attention profiles and that methylphenidate improves scores on test of continuous performance.

Adolescent↗

Attentional biases for alcohol cues in heavy and light social drinkers: the roles of initial orienting and maintained attention.

RATIONALE: There has been considerable theoretical interest in attentional biases for drug-related cues. However, there is little research on the component processes of such attentional biases. OBJECTIVES: We examined initial orienting to, and the maintenance of attention on, alcohol-related cues in heavy and light social drinkers. METHODS: The present study used a visual probe task to investigate biases in visual orienting to alcohol-related cues. We varied the presentation duration of alcohol-related pictures (200, 500 or 2000 ms) to investigate whether attentional biases operated in initial orienting or the maintenance of attention. RESULTS: In comparison with light social drinkers, heavy social drinkers had an attentional bias for alcohol pictures which were presented at the longer exposure durations (500 and 2000 ms), but not at the shorter duration of 200 ms. Subjective alcohol craving was correlated with the attentional bias index for alcohol pictures presented for 2000 ms. CONCLUSIONS: These results suggest that biases in visual orienting to alcohol-related cues in heavy social drinkers operate mainly in the processes involved in the maintenance of attention.

Adult↗

Active attention modulates passive attention-related neural responses to sudden somatosensory input against a silent background.

To reveal whether active attention modulates neuronal responses related to passive attention to somatosensory stimuli presented suddenly against a silent background, we examined the passive attention-related change in amplitude of the event-related brain potentials (ERPs), caused by temporal infrequency of stimuli. Eighteen healthy subjects performed passive and active attention tasks in two stimulus conditions. In the oddball condition, frequent (80%, standard) and infrequent (20%, deviant) electrical stimuli were randomly delivered to the second and third digits of the left hand. In the deviant-alone condition, the deviant stimulus (deviant-alone stimulus) was delivered with the same timing and sequence as in the oddball condition without standard stimuli. The P100, N140, and P200 elicited by the deviant-alone stimulus were enhanced in amplitude compared to those evoked by the oddball deviant stimulus in both the active and passive tasks. Moreover, active attention increased the enhancement of P100 and N140. The difference waveform (deviant-alone minus oddball deviant) provided similar findings. In conclusion, active attention enhances neural responses related to passive shifts of attention to somatosensory signals suddenly presented against a silent background. The results indicate that top-down signals for detecting target stimuli interact with passive shifts of attention caused by bottom-up signals.

Action Potentials↗

An electrophysiological investigation of the spatial distribution of attention to colored stimuli in focused and divided attention conditions.

In the present experiment ERPs were recorded to colored stimulus bars (red or blue) which were randomly presented at one out of eight different spatial locations on a visual display. The locations were situated on a hemi-circle around the fixation point, with four locations lying in each visual half-field. The subjects were instructed to attend to one stimulus location (the most peripheral left or right location: the relevant location) in a focused attention condition and to all four locations within the same visual half-field in a divided attention condition, and were instructed to respond to stimulus bars in one color presented at the relevant location(s). In the focused attention condition, spatial attention resulted in early positivity in the P1 latency range (ca. 100-175 ms), followed by a prolonged negativity in the N1, P2, and N2 latency range (ca. 175-350 ms). These effects generalized to locations in the same visual half-field as the relevant location. The effect of attending and responding to the target color consisted of a number of different effects. An early anterior positivity, occipital negativity was observed for the relevant location and for locations in the same visual half-field as the relevant location, but not for the locations in the opposite visual field. A later central negativity (N2b) appeared to be confined to the relevant location and one location adjacent to it. Finally, a late parietal positivity (P3b) was exclusively evoked by target stimuli at the relevant location. In the divided attention condition, the ERPs evoked by stimuli presented at each of the four locations within the relevant visual half-field showed increased early positivity (enhancing P1 amplitude) as compared to the ERPs to stimuli in the opposite (irrelevant) visual half-field. The early color selection effect was also found to all stimuli within the relevant half-field, but the N2b component was evoked both by stimuli within the relevant half-field and by stimuli at the location in the irrelevant half-field closest to the midline. The P3b was present to target stimuli at the three most lateral positions within the relevant half-field but it was absent to the relevant location closest to the midline. The data suggested that the attentional spotlight encompassed at least approximately 2 degrees in the focused attention condition, and an efficient selection by visual half-field in the divided attention situation.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

Dimensions of disordered attention in traumatic brain injury: further validation of the Moss Attention Rating Scale.

OBJECTIVES: To investigate the factor structure of disordered attention in moderate to severe, acute traumatic brain injury (TBI) and to use factor analysis and item response theory to further validate and refine an observational rating scale of attention for clinical and research purposes. DESIGN: Multicenter inception cohort. SETTING: Inpatient rehabilitation units. PARTICIPANTS: Patients with TBI (N=372) consecutively admitted to 8 Traumatic Brain Injury Model System centers within 2 weeks prior to observation, who consistently followed commands and who were on stable doses of all psychotropic medications for a 3-day rating period. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Participants were rated independently by treating occupational and physical therapists at an average of 1 month postinjury on the Moss Attention Rating Scale (MARS), a 45-item, Likert-type scale of attention-related behavior. RESULTS: Exploratory and confirmatory factor analyses revealed 3 correlated factors of disordered attention, interpreted as restlessness/distractibility, initiation, and sustained/consistent attention. Item response (Rasch) analysis was used to eliminate redundant items and to fill gaps in item difficulty. The resulting MARS consists of 22 items that can produce 3 factor scores and a total score that covers the broad construct of disordered attention. CONCLUSIONS: The factor-scored MARS has potential utility as a quantitative observational method with which to assess and study different dimensions of disordered attention in acute TBI, and to monitor change over time and treatment response within these dimensions.

Adolescent↗

Attentional modulation of the human somatosensory evoked potential in a trial-by-trial spatial cueing and sustained spatial attention task measured with high density 128 channels EEG.

We investigated the modulation of the somatosensory evoked potential (SEP) elicited by mechanical stimuli in a spatial sustained attention and a spatial trial-by-trial cueing design by means of high density electrode array EEG recordings. Subjects were instructed to detect rare tactile target stimuli at the to-be-attended hand while ignoring stimuli at the other hand. Analysis of the SEP revealed a highly complex pattern of results. The P50 component was significantly increased for attended stimuli in the sustained attention as opposed to the trial-by-trial cueing condition. However, no difference in amplitude was found for attended as opposed to unattended stimuli. High density electrode array recordings revealed a centero-frontal N140 component (N140c), which preceded the parietal N140 (N140p) by about 20 ms. The N140c exhibited an attention effect in particular in the trial-by-trial spatial cueing condition. The N140p was significantly enlarged with attention across both experimental conditions, but a closer inspection demonstrated that this was mainly due to the great attention effect in the trial-by-trial spatial cueing condition. The late positive component (190-380 ms after stimulus onset) exhibited a significant attention effect in both experimental conditions. The present experiment provides evidence that the attentional modulation of the SEP is different when tactile as opposed to electrical stimuli were used and when only somatosensory stimuli are presented with no further sensory stimulation in other modalities. Furthermore, transient as opposed to sustained spatial attention affected various components of the SEP in a different way.

Adult↗

Attentional disturbances in patients with unipolar psychotic depression: a selective and sustained attention study.

Psychotic depression is a clinical subtype of major depressive disorder in the recent editions of the psychiatric diagnostic systems ICD-10 (1992) and DSM-IV (1994). Recent evidence suggests that psychotic depressed patients are more impaired on neuropsychologic tests measuring attention as compared to nonpsychotic depressed patients. However, information on this issue between psychotic and nonpsychotic depression is limited. It has become clear that attention is not a single concept; thus we studied both selective and sustained attention using the theoretic model of automatic and controlled information processing. Thirty-two patients with major depressive disorder, 16 psychotics and 16 nonpsychotics, were investigated and compared with 20 patients with schizophrenic disorder and 20 healthy volunteers who comprised the control groups, using Ruff's 2 and 7 selective attention tests. Compared to the healthy controls, both depressed groups were impaired; however, the psychotic depressed group was more severely impaired on both measures. Attentional performance speed and accuracy scores, on both effortless and effortful conditions, were significantly lower in the psychotic depressed group than in the nonpsychotic depressed group. No significant differences were found on attentional performance between the psychotic depressed patients and those with schizophrenic disorder. Attention deficits are thus more prominent in psychotic than in nonpsychotic depression. Furthermore, taking attention as a criterion, psychotic depression, although of mood congruent subtype, lies closer to schizophrenia than to nonpsychotic depression.

Adult↗

Measuring sustained attention after traumatic brain injury: differences in key findings from the sustained attention to response task (SART).

Clinical reports after traumatic brain injury (TBI) suggest frequent difficulties with sustained attention, but their objective measurement has proved difficult. In 1997, Robertson and colleagues reported on a new sustained attention assessment tool, the sustained attention to response task (SART). Individuals with TBI were reported to produce more errors of commission on the SART than control participants, and both groups showed a relationship between SART errors and everyday lapses of attention as measured by the cognitive failures questionnaire (CFQ). Although few direct replications of these findings have been reported, the SART has been used widely as a measure of sustained attention in TBI, in normal controls, and in various other clinical samples. As part of a program of research on attention in TBI, we administered the SART and the CFQ to a sample of 34 survivors of moderate to severe TBI and to 35 control participants. CFQ scores reported by significant others showed clear group differences in everyday lapses of attention. Despite this, group differences in SART errors of commission were small and non-significant, and the correlations between SART errors and CFQ scores were small within both groups. Further analyses excluding participants with invalid score profiles, or restricting the analysis to the first performance of the SART failed to alter the results. These findings suggest that more research is needed to establish the validity of the SART as a measure of sustained attention after TBI, and to determine under what circumstances the original findings hold.

Adolescent↗

Shifts of attention in the early blind: an erp study of attentional control processes in the absence of visual spatial information.

To investigate the role of visual spatial information in the control of spatial attention, event-related brain potentials (ERPs) were recorded during a tactile attention task for a group of totally blind participants who were either congenitally blind or had lost vision during infancy, and for an age-matched, sighted control group who performed the task in the dark. Participants had to shift attention to the left or right hand (as indicated by an auditory cue presented at the start of each trial) in order to detect infrequent tactile targets delivered to this hand. Effects of tactile attention on the processing of tactile events, as reflected by attentional modulations of somatosensory ERPs to tactile stimuli, were very similar for early blind and sighted participants, suggesting that the capacity to selectively process tactile information from one hand versus the other does not differ systematically between the blind and the sighted. ERPs measured during the cue-target interval revealed an anterior directing attention negativity (ADAN) that was present for the early blind group as well as for the sighted control group. In contrast, the subsequent posterior late direction attention negativity (LDAP) was absent in both groups. These results suggest that these two components reflect functionally distinct attentional control mechanisms which differ in their dependence on the availability of visually coded representations of external space.

Acoustic Stimulation↗

Attention-based motion perception and motion adaptation: what does attention contribute?

Attention-based motion perception refers to the phenomenon that a stimulus with ambiguous motion energy can be seen to move in a direction that is under attentive control of the observer. The role of attention is obvious when the stimulus is ambiguous: it makes the stimulus move in one direction. The goal of the current experiment is to investigate what the contribution of attention under attentive tracking conditions actually is, especially while viewing-time progresses. We had our observers look at a circular array of four evenly spaced discs whose motion direction was biased in the clockwise direction. Observers either viewed the stimulus moving around a circular path passively or actively. In the latter case they attentively tracked one of the discs. The observer's task was to indicate the perceived direction of motion. As time progresses, this kind of stimulus will undergo spontaneous motion direction reversals. We analyzed the time course of the reversals and show that actively attentive tracking the stimulus massively delays the reversal time. These results suggest that attention can temporarily overrule lower level adaptation.

Adaptation, Physiological↗

Disengaging attention sets the temporal limit of attentive tracking.

At first sight, recent studies investigating the temporal limits of attentive tracking show contradictory outcomes. Attentively tracking an object in an ambiguous apparent motion display can have an upper limit of around 0.4 revolutions per second (rps) [Horowitz, T. S., Holcombe, A. O., Wolfe, J. M., Arsenio, H. C., & DiMase, J. S. (2004). Attentional pursuit is faster than attentional saccade. Journal of Vision, 4, 585-603] or 1rps [Verstraten, F. A., Cavanagh, P., & Labianca, A. T. (2000). Limits of attentive tracking reveal temporal properties of attention. Vision Research, 40, 3651-3664.]. Here, we demonstrate that this difference depends on presentation conditions: an important determinant for the temporal limit of attentive tracking appears to be the duty cycle. Tracking performance at high(er) rates decreases to chance with increasing duty cycle, while at low rates duty cycle hardly has an effect on performance. Results are discussed in terms of (dis)engagement of attention.

Attention↗

Multiple mechanisms of selective attention: differential modulation of stimulus processing by attention to space or time.

Two studies compared the modulatory effects of orienting attention to spatial locations versus temporal intervals using event-related potentials (ERPs). In both experiments subjects performed attentional orienting tasks, which used identical stimuli in both spatial and temporal orienting conditions. The first experiment (N=16) used bilateral peripheral targets (7.5 degrees eccentricity) at two different time intervals (600, 1200 ms after cue onset). During spatial orienting a symbolic central cue predicted (75% probability) the spatial location (left, right) of the relevant target. No information was given about the probable target interval (short, long). In temporal orienting the cue predicted the target interval but not its location. Valid cueing produced significantly shorter reaction times in both the spatial and temporal orienting conditions. ERPs to identical, non-target stimulus arrays were analysed, to isolate endogenous attentional mechanisms. Spatial and temporal attention had distinct modulatory effects upon stimulus processing. Focused spatial attention affected the amplitude of early visual components. Modulation by temporal attention started later, and mainly affected potentials linked to decisions and responses. The second experiment (N=12) used unilateral target stimuli, and equated the probability of stimulus occurrence at short and long time intervals and at left or right of fixation. The results confirmed the distinct pattern of modulation of stimulus processing by spatial and temporal orienting. The optimisation of behaviour by attention can thus be achieved as a consequence of distinct modulatory processes, illustrating the flexibility of attentional functions in the human brain.

Adult↗

Attentional modulation of the nociceptive processing into the human brain: selective spatial attention, probability of stimulus occurrence, and target detection effects on laser evoked potentials.

Laser evoked potentials (LEPs) are brain responses to activation of skin nociceptors by laser heat stimuli. LEPs consist of three components: N1, N2, and P2. Previous reports have suggested that in contrast to earlier activities (N1), LEPs responses after 230-250 ms (N2-P2) are modulated by attention to painful laser stimuli. However, the experimental paradigms used were not designed to specify the attentional processes involved in these LEP modulations. We investigated the effects of selective spatial attention and oddball tasks on LEPs. CO(2) laser stimuli of two different intensities were delivered on the dorsum of both hands of ten subjects. One intensity was frequently presented, and the other rarely. Subjects were asked to pay attention to stimuli delivered on one hand and to count rare stimuli, while ignoring stimuli on the other hand. Frequent and rare attended stimuli evoked enhanced N160 (N1) and N230 (N2) components in comparison to LEPs from unattended stimuli. Both components showed scalp distribution contralateral to the stimulus location. The vertex P400 (P2) was unaffected by spatial attention and stimulus location, but its amplitude increased after rare stimuli, whether attended or unattended. An additional parietal P600 component was induced by the attended rare stimuli. It is suggested that several attentional processes can modify nociceptive processing in the brain at different stages. LEP activities in the time-range of N1 and N2 (120-270 ms) showed evidence of processes modulated by the direction of spatial attention. Conversely, processes underlying P2 (400 ms) were not affected by spatial attention, but by the probability of the stimulus. This probability effect was not due to P3b-related processes that were observed at a later latency (600 ms). Indeed, P600 could be seen as a P3b evoked by conscious detection of rare targets.

Adult↗

Amblyopia decreases activation of the corticogeniculate pathway and visual thalamic reticularis in attentive rats: a 'focal attention' hypothesis.

In rats which were rendered monocular amblyopic by lid suturing one eye during a critical period, the intensity of neuronal activation in parts of the monocular segments of the striate cortex (layers 4 and 6) and lateral geniculate nucleus, and in the visual segment of the thalamic reticular nucleus, was determined after exploration of a novel-complex environment. Quantitative analysis of the number of Fos-labelled neurons per unit area showed that, in comparison to the structures contralateral to the normal eye, in the side contralateral to the deprived amblyopic eye there is a gradient of diminished activation. The strongest activation asymmetry was observed in the visual reticular segment, while in layers 6 and 4 of the visual cortex the activation asymmetry was less strong and weakest, respectively. In the lateral geniculate there was no Fos-detectable activation asymmetry. Furthermore, there was a positive correlation between the time rats spent in exploration and the degree of activation asymmetry in the visual reticular segment. From these results it is concluded: (1) Activation of the visual segment of the thalamic reticular nucleus in the alert, attentive animal is predominantly under visual cortical control via the cortico-reticulo-geniculate pathway originating in layer 6, because this layer showed activation asymmetry while the other visual input to reticularis, the geniculate, did not show this asymmetry. (2) Activation of the visual reticularis is a function of attention to the environment because its activation asymmetry was correlated to the amount of exploratory attentional behaviour. (3) Diminished activity in the cortico-reticulo-geniculate pathway originating in layer 6, and of visual reticularis, caused by visual deprivation during the critical period should be considered as additional etiological factors of the resulting amblyopia. The functional significance of these results is explained by a 'focal attention' hypothesis postulating that the observed activation of visual reticularis in exploring animals is necessarily a reflection of activation of the corticogeniculate pathway, because these axons innervate both the geniculate and the visual reticular segment. Mechanistically, a focus of animal's attention is transmitted in a top-down fashion from the extrastriate cortex, and from upper cortical layers, into striate cortex layer 6. In turn, activation of layer 6 cells corresponding to attentional foci generates a core of excitation in the geniculate by the direct glutamatergic corticogeniculate axons, and a surround inhibition by the disynaptic cortico-reticulo-geniculate (ultimately GABAergic) pathway. In the temporal domain, in light of recent results, activation of thalamic reticular nucleus visual segment will contribute to the induction of gamma oscillations in geniculocortical pathways and in their cortical targets. All together, these interactions result in increased effectiveness of thalamocortical transmission of features from the focalized visual scene. The postulated attention-dependent spatiotemporal influences on thalamocortical transmission would be a main function of the corticothalamic pathways in the awake, attentive animal.

Amblyopia↗

Processes in language acquisition: the roles of gender, attention, and maternal encouragement of attention over time.

This longitudinal study including 87 infant-mother dyads examined the relation between infant temperamental attention, maternal encouragement of attention, language, and the effects of gender. At ages 0;4, 0;8, and 1;0, global attention was assessed from Rothbart's (1981) IBQ; manipulative exploration was assessed with the Bayley (1969) IBR; and maternal verbal, visual and physical encouragement of attention were coded from 5 minutes of mother-infant free-play. At 1;0, language was measured using language items from the Bayley Mental Scale and parent-report items from Hendrick, Prather & Tobin's (1984) SICD-Revised. Multiple regressions indicated that gender, infants' manipulative exploration and maternal physical encouragement of attention at 0;4, and maternal verbal encouragement of attention at 1;0, were all positively related to language at 1;0. Interactions indicated that girls high in 0;8 or 1;0 manipulative exploration had more advanced language skills than girls low in manipulative exploration or than boys, regardless of their attention level. Additionally, maternal verbal encouragement of attention appears to be particularly salient in the development of language for boys.

Attention↗