Divided Attention Conditions Research Articles

Attention defines the context for implicit sensorimotor adaptation.

Movement errors are used to continuously recalibrate the sensorimotor map, a process known as sensorimotor adaptation. Here we examined how attention influences this automatic and obligatory learning process. Focusing first on spatial attention, we compared conditions in which the visual feedback that provided information about the movement outcome was either attended or unattended. Surprisingly, this manipulation had no effect on the rate of adaptation. We next used a dual-task methodology to examine the influence of attentional resources on adaptation. Here, again, we found no effect of attention, with the rate of adaptation similar under focused or divided attention conditions. Interestingly, we found that attention modulates adaptation in an indirect manner: Attended stimuli serve as cues that define the context for learning. The rate of adaptation was significantly attenuated when the attended stimulus changed from the end of one trial to the start of the next trial. In contrast, similar changes to unattended stimuli had no impact on adaptation. Together, these results suggest that visual attention defines the cues that establish the context for sensorimotor learning.

Long-term cognitive and affective consequences of mild traumatic brain injury: comparison with older adults

ABSTRACT Objective Memory and affective processing were compared in young adults with a remote mild traumatic brain injury (mTBI), to healthy younger and older adults. We evaluated memory performance when encoding was done under multi-tasking (divided attention) conditions, likely to exacerbate cognitive and psychological symptoms in mTBI. Methods Participants studied pairs of unrelated words under either full or divided attention conditions. Memory for single words (item memory) and for pairs of words (associative memory) was then assessed in sequential independent recognition tests, under full attention. Results Associative memory was poorer than item memory, and worse when encoding was done under divided than full attention. The decline in recognition accuracy from full to divided attention conditions on the associative memory test was significantly greater in mTBI compared to young adults and was similar in magnitude to that observed in older adults under full attention. Self-reported mental and total fatigue increased significantly as performance on the memory tests, following the divided attention condition, decreased, but only in the mTBI group. Conclusions Results show lingering memory deficits, and suggest that cognitive tasks may be experienced as psychologically more demanding in those with a mTBI, even months or years after injury.

The effect of target detection on memory retrieval.

Attention and memory are fundamental cognitive processes that closely interact. In the attentional boost effect (ABE), the stimuli that co-occur with targets are remembered better than those that co-occur with distractors in target detection tasks performed during memory encoding. In target detection tasks performed during retrieval, the stimuli that co-occur with targets are recognized as 'old' more easily than the stimuli that co-occur with distractors. This study mainly explored the internal mechanism of the effect of target detection on recognition. In Experiment 1, the full attention (FA; where participants performed only the memory task) condition was used to compare with divided attention (DA; where participants performed target detection while performing memory retrieval) condition to explore the impact of target detection and distraction inhibition on recognition. In Experiment 2, the proportion of old and new words in the retrieval stage was adjusted to 1:1 to eliminate the possible reaction tendency caused by the high proportion of old words. In Experiment 3, the presentation time of words was extended to 1.5 s and 3 s to eliminate the possible impact of rapid processing. The results indicated that the effect of target detection on recognition was attributed to both target detection and distraction rejection and is not affected by the ratio of old and new words and the word presentation time. The effect of target detection on recognition may be owing to temporal yoking of the dual tasks, which is different from the effect of target detection on memory encoding.

Severe processing capacity limits for sub-lexical features of letter strings

When reading, the visual system is confronted with many words simultaneously. How much of that information can a reader process at once? Previous studies demonstrated that low-level visual features of multiple words are processed in parallel, but lexical attributes are processed serially, for one word at a time. This implies that an internal bottleneck lies somewhere between early visual and lexical analysis. We used a dual-task behavioral paradigm to investigate whether this bottleneck lies at the stage of letter recognition or phonological decoding. On each trial, two letter strings were flashed briefly, one above and one below fixation, and then masked. In the letter identification experiment, participants indicated whether a vowel was present in a particular letter string. In the phonological decoding experiment, participants indicated whether the letter string was pronounceable. We compared accuracy in a focused attention condition, in which participants judged only one of the two strings, with accuracy in a divided attention condition, in which participants judged both strings independently. In both experiments, the cost of dividing attention was so large that it supported a serial model: participants were able to process only one letter string per trial. Furthermore, we found a stimulus processing trade-off that is characteristic of serial processing: When participants judged one string correctly, they were less likely to judge the other string correctly. Therefore, the bottleneck that constrains word recognition under these conditions arises at a sub-lexical level, perhaps due to a limit on the efficiency of letter recognition.

Value-directed retrieval: The effects of divided attention at encoding and retrieval on memory selectivity and retrieval dynamics.

Value-directed remembering refers to the tendency to best remember important information at the expense of less valuable information, and this ability may draw on strategic attentional processes. In six experiments, we investigated the role of attention in value-directed remembering by examining memory for important information under conditions of divided attention during encoding and retrieval. We presented participants with lists of words of varying objective or subjective value and compared participants completing the study phase under full or divided attention, in addition to participants completing the testing phase under full or divided attention. Results revealed that certain forms of selectivity were impaired when attention was divided during encoding but not when attention was divided during retrieval. Participants initiated recall (i.e., probability of first recall [PFR]) with high-value words as well as with words they subjectively deemed important; these value-mediated PFR retrieval dynamics resisted influence from reduced attentional resources during encoding and retrieval. Thus, while value-directed remembering involves both strategic encoding and retrieval operations, attentional resources during encoding appear crucial for subsequent recollection of valuable and important information; however, attentional resources during retrieval may be less influential in strategic selective memory. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

ERP evidence of attentional somatosensory processing and stimulus-response coupling under different hand and arm postures.

We investigated (1) the effects of divided and focused attention on event-related brain potentials (ERPs) elicited by somatosensory stimulation under different response modes, (2) the effects of hand position (closely-placed vs. separated hands) and arm posture (crossed vs. uncrossed forearms) on the attentional modulation of somatosensory ERPs, and (3) changes in the coupling of stimulus- and response-related processes by somatosensory attention using a single-trial analysis of P300 latency and reaction times. Electrocutaneous stimulation was presented randomly to the thumb or middle finger of the left or right hand at random interstimulus intervals (700-900 ms). Subjects attended unilaterally or bilaterally to stimuli in order to detect target stimuli by a motor response or counting. The effects of unilaterally-focused attention were also tested under different hand and arm positions. The amplitude of N140 in the divided attention condition was intermediate between unilaterally attended and unattended stimuli in the unilaterally-focused attention condition in both the mental counting and motor response tasks. Attended infrequent (target) stimuli elicited greater P300 in the unilaterally attention condition than in the divided attention condition. P300 latency was longer in the divided attention condition than in the unilaterally-focused attention condition in the motor response task, but remained unchanged in the counting task. Closely locating the hands had no impact, whereas crossing the forearms decreased the attentional enhancement in N140 amplitude. In contrast, these two manipulations uniformly decreased P300 amplitude and increased P300 latency. The correlation between single-trial P300 latency and RT was decreased by crossed forearms, but not by divided attention or closely-placed hands. Therefore, the present results indicate that focused and divided attention differently affected middle latency and late processing, and that hand position and arm posture also differently affected attentional processes and stimulus-response coupling.

Retrieval of temporal structure at recall can occur automatically

Temporal-structure, namely, the order in which events unfold over time, is one of the fundamental principles of episodic memory organization. A seminal empirical demonstration of the prominence of temporal structure in memory organization is the Temporal Contiguity Effect (TCE), whereby the proximity between two items at encoding predicts the likelihood of those two items being retrieved consecutively during recall. Recent studies have found that TCE occurs under a wide variety of conditions in which strategic control processes at encoding are reduced or even eliminated. This suggests that the encoding of temporal structure occurs automatically. Extending these findings, in the current study we asked whether the retrieval of temporal structure, as reflected by indices of the TCE, is influenced by strategic control processes at retrieval. To manipulate participants' ability to rely on strategic control processes, we compared standard recall performance (Full Attention condition) to a condition in which attention was divided between recall and a concurrent task (Divided Attention condition), which has been shown to disrupt such control processes. Across two experiments—one with standard encoding conditions and one with continual distraction during encoding—we found no differences in any index of the TCE between the two conditions. These results are all the more striking considering that in both experiments, dividing attention negatively affected overall recall performance compared to the Full Attention condition. Thus, while recall performance is reduced when disrupting strategic processes, the ability to use temporal structure to drive recall is not affected.

Can divided attention at retrieval improve memory? Effects of target detection during recognition

ABSTRACT The attentional boost effect (ABE) is an improvement of memory under divided attention conditions in which stimulus encoding is enhanced when a target is detected in a simultaneous target-monitoring distracting task. Here we asked whether memory is similarly improved when the target-monitoring task occurs at the time of retrieval. In four experiments, participants encoded words under full attention then completed a recognition test under either divided attention, during which participants made recognition judgments while performing the target-monitoring task, or full attention, in which the target-monitoring task was not performed. Relative to distractor rejection, target detection increased hits and false alarms under divided attention with no net effect on discrimination. Targets and distractors had no effect on recognition under full attention. The target-related increase in hits and false alarms occurred regardless of whether the target-monitoring material matched or mismatched the test material and regardless of the target-to-distractor ratio and the target response. A change in bias accounts for the phenomenon, in which participants adopt a more lenient criterion for target-paired words than for distractor-paired words. The same divided attention manipulation that enhances memory at encoding does not similarly enhance memory at retrieval. Theoretical explanations are discussed.

The influence of magnocellular and parvocellular visual information on global processing in White and Asian populations.

Humans have the remarkable ability to efficiently group elements of a scene together to form a global whole. However, cross-cultural comparisons show that East Asian individuals process scenes more globally than White individuals. This experiment presents new insights into global processing, revealing the relative contributions of two types of visual cells in mediating global and local visual processing in these two groups. Participants completed the Navon hierarchical letters task under divided-attention conditions, indicating whether a target letter "H" was present in the stimuli. Stimuli were either 'unbiased', displayed as black letters on a grey screen, or biased to predominantly process low spatial frequency information using psychophysical thresholds that converted unbiased stimuli into achromatic magnocellular-biased stimuli and red-green isoluminant parvocellular-biased stimuli. White participants processed stimuli more globally than Asian participants when low spatial frequency information was conveyed via the parvocellular pathway, while Asian participants showed a global processing advantage when low spatial frequency information was conveyed via the magnocellular pathway, and to a lesser extent through the parvocellular pathway. These findings suggest that the means by which a global processing bias is achieved depends on the subcortical pathway through which visual information is transmitted, and provides a deeper understanding of the relationship between global/local processing, subcortical pathways and spatial frequencies.

Attention and Memory in Depersonalization-Spectrum Dissociative Disorders: Impact of Selective-Divided Attentional Condition, Stimulus Emotionality, and Stress

ABSTRACT We investigated cognition in depersonalization-spectrum dissociative disorders without comorbid posttraumatic stress disorder to explore evidence for emotionally avoidant information processing. Forty-eight participants with DSM-IV dissociative disorder (DD) (Depersonalization Disorder – 37, Dissociative Disorder NOS −11), 36 participants with Posttraumatic Stress Disorder (PTSD), and 56 healthy controls (HC) were administered the Weschler Adult Intelligence Scale-III (WAIS); the Weschler Memory Scale-III (WMS); and three Stroop tasks: the Standard Stroop, a selective-attention Emotional Stroop using neutral, dissociation, and trauma-related word categories, and a divided-attention Emotional Stroop using comparable words. Participants were also administered a paired-associates explicit and implicit memory test using emotionally neutral and negative words, before and after the Trier Social Stress Test. The DD and HC groups had comparable general intelligence and memory scores, though dissociation severity was inversely related to verbal comprehension and working memory. In the selective-attention condition, DD participants showed greater incidental recall across word categories with comparable interference. However in the divided-attention condition, DD participants significantly favored lesser attentional interference at the expense of remembering words. Across attentional conditions, DD participants had better recall for disorder-related than neutral words. Pre-stress, the DD group demonstrated better explicit memory for neutral versus negative words with reversal after stress, whereas the HC group demonstrated the opposite pattern; implicit memory did not differ. Cognition in the PTSD control group was generally dissimilar to the DD group. The findings in toto provide substantial evidence for emotionally avoidant information processing in DD, vulnerable to the impact of stress, at the level of both attention and memory.

Perception of temporal cues in word segments under bimodal divided attention in simulated cochlear implant listening

Auditory temporal processing is important for cochlear-implant (CI) users to understand speech. Speech processing often unfolds along with sensory inputs from other modalities. This study examined whether dividing attention across modalities affects temporal processing of word segments in simulated CI listening. Adults with normal hearing performed categorization tasks on unprocessed and 8-channel vocoded versions of a Dish-Ditch contrast with varying silent intervals preceding the word-final fricative. The categorization performance was measured concurrently with a visual working memory task on meaningless images. This divided attention (AV-div) condition was compared with an audiovisual selective attention (AV-sel) condition in which participants focused on the categorization task and ignored the visual stimuli, and with an auditory-only (AO) condition in which participants performed the categorization task without the visual stimuli. Preliminary results (N = 5) revealed that participants tended to report more “Dish” responses for words with longer silence intervals under the two AV conditions than the AO condition, especially for the AV-div condition. The AV-related effects on the categorization performance appear to be reduced for vocoded than unprocessed words. These results suggest that concurrent visual information affects auditory temporal processing, which might lead to speech understanding difficulties of CI users in multisensory contexts.

Short-Term Consolidation of Information for Episodic Memory: The Role of Attention

Pieces of evidence from rapid serial visual presentation, attentional blink, and dual-task interference phenomena propose that human beings have a significant limitation on the short-term consolidation process. Short-term consolidation is transferring perceptual representations to a more durable form of memory. Although previous research has shown that masks presented after targets interrupt the consolidation process of information, there is not enough evidence for the role of attention in consolidation for episodic memory. Three experiments were conducted to investigate the effects of attention and stimulus onset asynchrony (SOA) between targets and masks on episodic memory. Masks were presented after targets with varying SOAs. The participants in the divided attention condition performed the attention-demanding secondary task after the presentation of the masks, whereas participants in the full attention condition were not requested to perform the secondary task after the presentation of masks. The results showed that reducing SOA between targets and masks caused an impairment in memory performance for divided attention but not for full attention, providing evidence for the necessity of attention for the short-term consolidation process.

A simulation of older adults' associative memory deficit using structural process interference in young adults.

Associative memory deficit underlies a part of older adults' deficient episodic memory due to the reduced ability to bind units of information. In this article we further assess the mechanism underlying this deficit, by assessing the degree to which we can model it in young adults under conditions of divided attention. We shall describe two experiments in this paper; these experiments investigate item and associative recognition in young adults under full- or divided-attention conditions. The secondary tasks employed were N-back like (NBL), which serves as a working memory updating task, and parity judgement and visuospatial (VS) tasks, which serve as non-working memory tasks. The results of both experiments show that only the NBL specifically affected associative recognition, while the other tasks affected item and associative memory to the same degree, indicating a general resource competition. These results presented a convergence of evidence for the associative deficit in older adults by modelling it in young adults.

The Grouping-Induced Numerosity Illusion Is Attention-Dependent.

Perceptual grouping and visual attention are two mechanisms that help to segregate visual input into meaningful objects. Here we report how perceptual grouping, which affects perceived numerosity, is reduced when visual attention is engaged in a concurrent visual task. We asked participants to judge the numerosity of clouds of dot-pairs connected by thin lines, known to cause underestimation of numerosity, while simultaneously performing a color conjunction task. Diverting attention to the concomitant visual distractor significantly reduced the grouping-induced numerosity biases. Moreover, while the magnitude of the illusion under free viewing covaried strongly with AQ-defined autistic traits, under conditions of divided attention the relationship was much reduced. These results suggest that divided attention modulates the perceptual grouping of elements by connectedness and that it is independent of the perceptual style of participants.

Speech fluency in bilinguals who stutter: Language proficiency and attentional demands as mediating factors

PurposeThe current study examines how speech disfluencies manifest themselves in the two languages of bilingual persons who stutter, starting from the hypothesis that stuttering is associated with an attentional deficit at the level of speech production. MethodsTwenty-eight bilingual people who stutter performed a spontaneous and a controlled speech production task, once in their dominant and once in their non-dominant language. The controlled production task (i.e. a network description task) was carried out once under a full-attention condition and once under a divided-attention condition where a non-linguistic, pitch discrimination task was performed simultaneously. ResultsIn both the spontaneous and the controlled speech task, bilingual persons who stutter produced more (typical and stuttering-like) disfluencies in their L2 than in their L1. Furthermore, whereas the typical disfluencies increased when attention was directed away from speech production, stuttering-like disfluencies decreased. This effect was however restricted to L2. In addition, L2 proficiency was generally found to be a predicting factor, with higher proficiency leading to fewer disfluencies. ConclusionsThese results suggest that speaking in a non-dominant language increases both typical and stuttering-like disfluencies in bilingual persons who stutter, but also that these two types of dysfluencies differ regarding their attentional origins. Our findings offer further support for attentional accounts of stuttering and have both theoretical and clinical implications.

Sex hormones modulate sex differences and relate to hemispheric asymmetries in a divided visual field Navon task

Sex differences in functional hemispheric asymmetries (FHA) have been hypothesized as a fundamental mechanism behind sex differences in global-local processing. So far, it has not been assessed how interactive effects of sex and hemifield presentation influence common indicators of global precedence. The current study is the first to investigate the involvement of FHAs by using a divided visual field Navon paradigm and controlling for sex hormone status. Moreover, various factors that have previously shown a reliable influence on global-local processing performance are verified within the context of unilateral presentation. 39 men and 39 naturally cycling women in their luteal cycle phase completed a divided visual field Navon task with the instruction to detect targets either at any level (divided attention) or only at the global or local level (selective attention) in three different spacing conditions. The obtained evidence reveals significant sex differences in the global advantage effect (faster reaction to global vs. local level targets) for densely spaced letter stimuli, as well as significant sex differences in global-local level interference, with findings on both measures being mediated by testosterone. Also, estradiol showed different relationships to the global advantage effect in men and women together with a positive relationship to global advantage for the selective attention condition. Behavioural reaction time results were mirrored by accuracy measures but presented significantly higher global- over local-level accuracy in women compared to men for the divided attention condition. Our results did not show significant sex differences in FHAs but indicate differential relationships between progesterone and FHAs in men and women. In conclusion, sex hormones emerged as central mediators of sex differences in global precedence and possible moderators of hemispheric asymmetries.

Selective memory disrupted in intra-modal dual-task encoding conditions.

Given natural memory limitations, people can generally attend to and remember high-value over low-value information even when cognitive resources are depleted in older age and under divided attention during encoding, representing an important form of cognitive control. In the current study, we examined whether tasks requiring overlapping processing resources may impair the ability to selectively encode information in dual-task conditions. Participants in the divided-attention conditions of Experiment 1 completed auditory tone-distractor tasks that required them to discriminate between tones of different pitches (audio-nonspatial) or auditory channels (audio-spatial), while studying items in different locations in a grid (visual-spatial) differing in reward value. Results indicated that, while reducing overall memory accuracy, neither cross-modal auditory distractor task influenced participants' ability to selectively encode high-value items relative to a full attention condition, suggesting maintained cognitive control. Participants in Experiment 2 studied the same important visual-spatial information while completing demanding color (visual-nonspatial) or pattern (visual-spatial) discrimination tasks during study. While the cross-modal visual-nonspatial task did not influence memory selectivity, the intra-modal visual-spatial secondary task eliminated participants' sensitivity to item value. These results add novel evidence of conditions of impaired cognitive control, suggesting that the effectiveness of top-down, selective encoding processes is attenuated when concurrent tasks rely on overlapping processing resources.

The age-related associative deficit simulated by relational divided attention: encoding strategy and recollection

ABSTRACT According to the associative deficit hypothesis, older adults experience greater difficulty in remembering associations between pieces of information than young adults, despite their relatively intact memory for individual items. It has been demonstrated that this deficit could be simulated by depleting resources for relational processing. The current study examines the possible mechanisms underlying this simulation. Item and associative memory were assessed using a process dissociation paradigm in which word pairs were encoded under full attention (FA) or relational divided attention (DA) conditions across three groups: FA older adults (n = 24), FA young adults (n = 24), and DA young adults (n = 24). Recollection and familiarity were estimated for the associative memory performance. Relative to FA young adults, both older adults and DA young adults showed an associative deficit, and reduced use of recollection and high-level relational encoding strategies. Regression analyses suggested that the effects of age and DA on associative memory were largely driven by the variance in recollection and encoding strategy use. The results suggest that depletion of attentional resources for relational processing impairs associative memory through disrupting the use of effective encoding strategies and recollection, which largely simulates age-related associative deficit.

Effects of the Attention Training Technique on Brain Activity in Healthy University Students Assessed by EEG Source Imaging.

This study aimed to investigate the neurocognitive effects of the Attention Training Technique (ATT) on brain activity in healthy participants. The participants included 20 university students who were asked to practice ATT as a homework assignment for 20 days. The intracerebral source localization of their electroencephalogram during rest and the ATT task, which comprised selective attention, attention switching, and divided attention conditions, was evaluated by standardized low-resolution brain electromagnetic tomography. Brain activity during rest was subtracted from that during the ATT task, and that was compared before and after the homework assignment. The results for the divided attention condition indicated significantly decreased alpha 1 frequency band power in the left orbital frontal cortex (OFC) and alpha 2 power in the right inferior temporal cortex. Further, decreased alpha 1 power in the left OFC correlated with reduced subjective difficulty during the divided attention condition. One possibility is that the brain activity changed as the effect of ATT practice, although this study cannot confirm causality. Further studies are required which include a control group that would complete similar training without the ATT task.

The coordinate system of endogenous spatial attention during smooth pursuit.

A central question in vision is whether spatial attention is represented in an eye-centered (retinotopic) or world-centered (spatiotopic) reference-frame. Most previous studies on this question focused on how coordinates are modulated across saccades. In the present study, we investigated the reference-frame of attention across smooth pursuit eye-movements using a goal-directed saccade task. In two experiments, participants were asked to pursue a moving target while attending to one or two grating stimuli. On each trial, one stimulus was constant in its retinal position and the other was constant in its spatial position. Upon detection of a slight change in stimulus orientation, participants were asked to stop pursuing and perform a fast saccade toward the modified stimulus. In the focused attention condition, they attended one, predefined, stimulus, and in the divided attention condition they attended both. In Experiment 1 the angle of the orientation change marking the target event was constant across participants and conditions. In Experiment 2, the angle was individually adapted to equate performance across participants and conditions. Findings of the two experiments were consistent and showed that the enhancement of mean visual sensitivity in the focused relative to the divided attention condition was similar in magnitude for both retinotopic and spatiotopic targets. This indicates that during smooth pursuit, endogenous attention was proportionally divided between targets in retinotopic and spatiotopic frames of reference.