Selective attention and cerebral dominance in perceiving and responding to speech messages

The effect of attention on cerebral dominance and the asymmetry between left and right ears was investigated using a selective listening task. Right handed subjects were presented with simultaneous dichotic speech messages; they shadowed one message in either the right or left ear and at the same time tapped with either the right or the left hand when they heard a specified target word in either message. The ear asymmetry was shown only when subjects' attention was focused on some other aspect of the task: they tapped to more targets in the right ear, but only when these came in the non-shadowed message; they made more shadowing errors with the left ear message, but chiefly for non-target words. The verbal response of shadowing showed the right ear dominance more clearly than the manual response of tapping. Tapping with the left hand interfered more with shadowing than tapping with the right hand, but there was little correlation between the degree of hand and of ear asymmetry over individual subjects. The results support the idea that the right ear dominance is primarily a quantitative difference in the distribution of attention to left and right ear inputs reaching the left hemisphere speech areas. This affects both the efficiency of speech perception and the degree of response competition between simultaneous verbal and manual responses.     

Effects of divided attention and word concreteness on correct recall and false memory reports

Lists of thematically related words were presented to participants with or without a concurrent task. In Experiments 1 and 2, respectively, English or Spanish word lists were either low or high in concreteness (concrete vs abstract words) and were presented, respectively, auditorily or visually for study. The addition of a concurrent visual or auditory task, respectively, substantially reduced correct recall and doubled the frequency of false memory reports (nonstudied critical or theme words). Divided attention was interpreted as having reduced the opportunity for participants to monitor successfully their elicitations of critical associates. Comparisons of concrete and abstract lists revealed significantly more recalls of false memories for abstract than concrete word lists. Comparisons between two levels of attention, two levels of word concreteness, and two presentation modalities failed to support the "more is less" effect by which enhanced correct recall is accompanied by increased frequencies of false memories.     

Effects of bilingualism, aging, and semantic relatedness on memory under divided attention.

We examined how encoding and retrieval processes were affected by manipulations of attention, and whether the degree of semantic relatedness between words in the memory and distracting task modulated these effects. We also considered age and bilingual status as mediating factors. Monolingual and bilingual younger and older adults studied a list of words from a single semantic category presented auditorily, and later free recalled them aloud. During either study or retrieval, participants concurrently performed a distracting task requiring size decisions to words from either the same or a different semantic category as the words in the memory task. The greatest disruptions of memory from divided attention (DA) were for encoding rather than retrieval. The effect of semantic relatedness was significant only for DA at encoding. Older age and bilingualism were associated with lower recall scores in all conditions, but these factors did not influence the magnitude of memory interference. The results suggest that encoding is more sensitive to semantic similarity in a distracting task than is retrieval. The role of attention at encoding and retrieval is discussed.     

Presentation format effects in working memory: The role of attention

Four experiments are reported in which participants attempted to remember three or six concrete nouns, presented as pictures, spoken words, or printed words, while also verifying the accuracy of sentences. Hypotheses meant to explain the higher recall of pictures and spoken words over printed words were tested. Increasing the difficulty and changing the type of processing task from arithmetic to a visual/spatial reasoning task did not influence recall. An examination of long-term modality effects showed that those effects were not sufficient to explain the superior performance with spoken words and pictures. Only when we manipulated the allocation of attention to the items in the storage task by requiring the participants to articulate the items and by presenting the stimulus items under a degraded condition were we able to reduce or remove the effect of presentation format. The findings suggest that the better recall of pictures and spoken words over printed words result from the fact that under normal presentation conditions, printed words receive less processing attention than pictures and spoken words do.     

Cross-modal selective attention: on the difficulty of ignoring sounds at the locus of visual attention

In three experiments, we investigated whether the ease with which distracting sounds can be ignored depends on their distance from fixation and from attended visual events. In the first experiment, participants shadowed an auditory stream of words presented behind their heads, while simultaneously fixating visual lip-read information consistent with the relevant auditory stream, or meaningless "chewing" lip movements. An irrelevant auditory stream of words, which participants had to ignore, was presented either from the same side as the fixated visual stream or from the opposite side. Selective shadowing was less accurate in the former condition, implying that distracting sounds are harder to ignore when fixated. Furthermore, the impairment when fixating toward distractor sounds was greater when speaking lips were fixated than when chewing lips were fixated, suggesting that people find it particularly difficult to ignore sounds at locations that are actively attended for visual lipreading rather than merely passively fixated. Experiments 2 and 3 tested whether these results are specific to cross-modal links in speech perception by replacing the visual lip movements with a rapidly changing stream of meaningless visual shapes. The auditory task was again shadowing, but the active visual task was now monitoring for a specific visual shape at one location. A decrement in shadowing was again observed when participants passively fixated toward the irrelevant auditory stream. This decrement was larger when participants performed a difficult active visual task there versus fixating, but not for a less demanding visual task versus fixation. The implications for cross-modal links in spatial attention are discussed.     

高感觉寻求者对危险意义声音的自动加工优势：N1、P2和MMN的证据

Zuckerman关于感觉寻求特质的唤醒理论认为,高感觉寻求者为提高其大脑唤醒,会不惜以冒险方式来寻求高强度、变化、新异和复杂的刺激经验。既往研究已经证实了高感觉寻求者对高强度的、变化的和新奇的刺激材料的认知加工偏向,但尚缺乏来自复杂的和具有危险意义刺激材料的研究证据。我们运用反转Oddball实验范式,以听觉N1、P2和MMN（Mismatch negativity）为ERPs指标,系统比较了高、低感觉寻求者对危险意义声音的自动唤醒、注意偏向和特征探测这三个方面的认知加工差异。结果发现,高感觉寻求者的N1、P2和MMN波幅均显著大于低感觉寻求者。结果表明,高感觉寻求者对危险意义声音产生了更高的唤醒水平、注意偏向和特征探测自动加工优势,这些优势可能是其偏于冒险行为的认知神经机制。     

Self‐oriented perfectionism and its relationship to selective attention: An experimental examination using social cognitive paradigm1

The cognitive biases associated with perfectionism include a selective attention to failure and the discounting of success. The present study experimentally focused on the relation between self‐oriented perfectionism (SOP) and selective attention using the social cognitive paradigm. Forty undergraduate students who were identified as either high or low in SOP were asked to perform modified versions of the Stroop task. The results suggest that participants with high SOP did not take longer to respond to failure words than to neutral words, but their reaction time to failure words was longer than that of participants with low SOP. These findings provided the basis for cognitive behavioral biases for perfectionism.     

Depth of nontarget processing in an attention task

Two studies examined the effect of the sensory discriminability of targets from nontargets on depth of nontarget processing. Subjects shadowed target words that were binaurally presented with coincident nontarget words. Targets and nontargets were spoken in the same male voice under low sensory discriminability and in male and female voices, respectively under high sensory discriminability. Across the two studies, depth of nontarget processing was assessed in three ways: extent to which shadowing accuracy was disrupted by a semantic overlap between targets and nontargets, expenditure of capacity (reaction time to subsidiary light signals), and nontarget recall. All three possible measures of depth of nontarget processing decreased as sensory discriminability increased. The data support the assumption of multiple-loci theories of attention that nontargets can be perceptually inhibited; they contraindicate the assumption of late-selection theories that perceptual processing is automatic and irrepressible.     

Are attentional resources a mediator for sex differences in memory?

The divided attention paradigm was used to investigate sex differences in encoding and retrieval processes of memory. Participants performed a memory and reaction time (RT) task under full attention and two divided attention conditions, that is, at encoding and retrieval. Results revealed that females recalled significantly more words than males under the full attention and divided attention at encoding conditions. Results further showed that secondary task costs were larger for males than females during divided attention at retrieval. Furthermore, regardless of sex, recall was best under full attention and worst under divided attention at encoding conditions. In relation to the RT task, RTs were shorter under full attention and longer under the divided attention at retrieval condition. Overall, these results show that females recall more words than males possibly due to a more severe effect of reduced attention during encoding than retrieval for males. The current findings thus suggest that a reduction in attentional resources may mediate sex‐related decreases in word recall.     

Relations between emotion,memory, and attention: Evidence from taboo Stroop,lexical decision,and immediate memory tasks

This article reports five experiments demonstrating theoretically coherent effects of emotion on memory and attention. Experiments 1-3 demonstrated three taboo Stroop effects that occur when people name the color of taboo words. One effect is longer color-naming times for taboo than for neutral words, an effect that diminishes with word repetition. The second effect is superior recall of taboo words in surprise memory tests following color naming. The third effect is better recognition memory for colors consistently associated with taboo words rather than with neutral words. None of these effects was due to retrieval factors, attentional disengagement processes, response inhibition, or strategic attention shifts. Experiments 4 and 5 demonstrated that taboo words impair immediate recall of the preceding and succeeding words in rapidly presented lists but do not impair lexical decision times. We argue that taboo words trigger specific emotional reactions that facilitate the binding of taboo word meaning to salient contextual aspects, such as occurrence in a task and font color in taboo Stroop tasks.     

The effect of reinforcement and verbal rehearsal on selective attention in learning-disabled children

A central-incidental task of selective attention was administered to 100 learning-disabled boys — 48 younger children (81/2–101/2 years) and 52 older children (101/2–121/2 years). Subjects at both age levels were assigned to one of four conditions: (a) a standard condition; (b) a rehearsal condition, in which subjects were taught a verbal rehearsal strategy; (c) a reinforcement condition, in which correct responses were rewarded; and (d) a combined rehearsal-reinforcement condition. Older subjects recalled more central task but not more incidental task information than younger subjects. A measure of selective attention efficiency was also greater for older than for younger subjects. Central recall in the rehearsal-reinforcement condition was greater than in any other condition. Central recall was greater in the rehearsal condition than in the standard and reinforcement conditions. Selective attention efficiency was greater for both rehearsal conditions than for both nonrehearsal conditions. Incidental recall was higher for reinforcement subjects than for rehearsal subjects. Results suggest that induced verbal rehearsal improves central recall and selective attention in learning-disabled children. Reinforcement alone does not improve central recall but may when paired with rehearsal.This article is based on a Ph.D. dissertation completed by the senior author at the University of Virginia. Preparation of this article was supported in part by a contract (300-77-0495) from the Bureau of Education for the Handicapped, Office of Education, for the University of Virginia Learning Disabilities Research Institute.     

Working memory and flexibility in awareness and attention

We argue that attention and awareness form the basis of one type of working-memory storage. In contrast to models of working memory in which storage and retrieval occur effortlessly, we document that an attention-demanding goal conflict within a retrieval cue impairs recall from working memory. In a conceptual span task, semantic and color-name cues prompted recall of four consecutive words from a twelve-word list. The first-four, middle-four, and final-four words belonged to different semantic categories (e.g., body parts, animals, and tools) and were shown in different colors (e.g., red, blue, and green). In Experiment 1, the color of the cue matched that of cued items 75% of the time, and the rare mismatch impaired recall. In Experiment 2, though, the color of the cue matched that of the cued items only 25% of the time, and the now-more-frequent mismatches no longer mattered. These results are difficult to explain with passive storage alone and indicate that a processing difficulty impedes recall from working memory, presumably by distracting attention away from its storage function.     

Mood-congruent attention and memory bias in dysphoria: Exploring the coherence among information-processing biases

Recent studies indicate that depression is characterized by mood-congruent attention bias at later stages of information-processing. Moreover, depression has been associated with enhanced recall of negative information. The present study tested the coherence between attention and memory bias in dysphoria. Stable dysphoric (n = 41) and non-dysphoric (n = 41) undergraduates first performed a spatial cueing task that included negative, positive, and neutral words. Words were presented for 250 ms under conditions that allowed or prevented elaborate processing. Memory for the words presented in the cueing task was tested using incidental free recall. Dysphoric individuals exhibited an attention bias for negative words in the condition that allowed elaborate processing, with the attention bias for negative words predicting free recall of negative words. Results demonstrate the coherence of attention and memory bias in dysphoric individuals and provide suggestions on the influence of attention bias on further processing of negative material.     

Speech shadowing while driving: on the difficulty of splitting attention between eye and ear

Abstract - We investigated the role of cross-modal links in spatial attention in modulating the efficiency of dual-task performance. The difficulty of combining speech shadowing with a simulated driving task was modulated by the spatial location from which the speech was presented. In both single- and dual-task conditions, participants found it significantly easier to shadow one of two auditory streams when the relevant speech was presented from directly in front of them, rather than from the side. This frontal speech advantage was more pronounced when participants performed the demanding simulated driving task at the same time as shadowing than when they performed the shadowing task alone. These results demonstrate that people process auditory information more efficiently (with a lower overall dual-task decrement) when relevant auditory and visual stimuli are presented from the same, rather than different, spatial locations. These results are related to recent findings showing that there are extensive cross-modal links in spatial attention, and have clear implications for the design of better user interfaces.     

Individual differences in working memory capacity and divided attention in dichotic listening

The controlled attention theory of working memory suggests that individuals with greater working memory capacity (WMC) are better able to control or focus their attention than individuals with lesser WMC. This relationship has been observed in a number of selective attention paradigms including a dichotic listening task (Conway, Cowan, & Bunting, 2001) in which participants were required to shadow words presented to one ear and ignore words presented to the other ear. Conway et al. found that when the participant’s name was presented to the ignored ear, 65% of participants with low WMC reported hearing their name, compared to only 20% of participants with high WMC, suggesting greater selective attention on the part of high WMC participants. In the present study, individual differences in divided attention were examined in a dichotic listening task, in which participants shadowed one message and listened for their own name in the other message. Here we find that 66.7% of high WMC and 34.5% of low WMC participants detected their name. These results suggest that as WMC capacity increases, so does the ability to control the focus of attention, with high WMC participants being able to flexibly “zoom in” or “zoom out” depending on task demands.     

Shadowing and monitoring for selective attention

Although shadowing has been assumed to hold attention strongly (e.g. Hochberg, 1970) this has not been demonstrated, and the incidence of errors and intrusions suggest that it is not as powerful a technique as might have been supposed. An alternative, simpler, technique would be monitoring, but Kahneman (1970) maintains that selectivity fails in the absence of a continuous response. The experiments here compare the shadowing and monitoring tasks when attentional selectivity was required, and when it was not required, and indicate that similar attentional strategies operate during the monitoring and shadowing of brief messages. The shadowing paradigm is criticized in terms of an interaction between the relative resemblance of the stimuli and the shadowing voice. It is not demonstrated that an absolute interaction takes place, but more importantly that relatively greater interference is apparent when the shadower's voice and the stimuli to be shadowed are similar than when they are distinct. It is suggested that low target detections in the unattended message may be an artifact of the processing requirements of the shadowing task.     

Encoding tasks dissociate the effects of divided attention on category-cued recall and category-exemplar generation

The combined effects of encoding tasks and divided attention upon category-exemplar generation and category-cued recall were examined. Participants were presented with pairs of words each comprising a category name and potential example of that category. They were then asked to indicate either (i) their liking for both of the words or (ii) if the exemplar was a member of the category. It was found that divided attention reduced performance on the category-cued recall task under both encoding conditions. However, performance on the category-exemplar generation task remained invariant across the attention manipulation following the category judgment task. This provides further evidence that the processes underlying performance on conceptual explicit and implicit memory tasks can be dissociated, and that the intentional formation of category-exemplar associations attenuates the effects of divided attention on category-exemplar generation.     

工作记忆负荷对无意注意的影响

通过探讨工作记忆负荷对无意注意的影响,考察工作记忆的认知控制功能对选择性注意的作用机制。为了避免工作记忆和选择注意的目标或者干扰子之间的知觉注意资源的竞争,采用言语工作记忆任务和视觉空间位置辨别任务,同时视觉干扰刺激采用被试无法识别的韩语。结果发现,在高负荷条件下,干扰效应显著;而在低和中负荷条件下,没有观察到干扰效应。说明在高负荷条件下,被试没有额外的资源来抑制干扰加工,从而出现了显著的干扰效应。由此,本研究支持负荷理论的观点：工作记忆在选择性注意中执行认知控制功能。     

Selective attention for cardiac information in panic patients

With various reaction time paradigms, panic patients have been shown to have selective attention for threatening sensations. However, almost all of these paradigms use words describing sensations and not the threatening sensations themselves. To increase the ecological validity, in the current study selective attention for heartbeat information was measured with a paradigm derived from the dot probe detection task but using 'real' heartbeat information instead of words. The results indeed showed selective attention for ECG information in panic patients. However, an accelerated ECG did not attract the attention of panic patients more than a slower ECG. Against expectation, both panic patients and normal controls shifted their attention away from an accelerated ECG. Possible explanations are explored.