Cognitive control in media multitaskers: Two replication studies and a meta-Analysis

Ophir, Nass, and Wagner (2009, Proceedings of the National Academy of Sciences of the United States of America, 106(37), 15583–15587) found that people with high scores on the media-use questionnaire—a questionnaire that measures the proportion of media-usage time during which one uses more than one medium at the same time—show impaired performance on various tests of distractor filtering. Subsequent studies, however, did not all show this association between media multitasking and distractibility, thus casting doubt on the reliability of the initial findings. Here, we report the results of two replication studies and a meta-analysis that included the results from all published studies into the relationship between distractor filtering and media multitasking. Our replication studies included a total of 14 tests that had an average replication power of 0.81. Of these 14 tests, only five yielded a statistically significant effect in the direction of increased distractibility for people with higher scores on the media-use questionnaire, and only two of these effects held in a more conservative Bayesian analysis. Supplementing these outcomes, our meta-analysis on a total of 39 effect sizes yielded a weak but significant association between media multitasking and distractibility that turned nonsignificant after correction for small-study effects. Taken together, these findings lead us to question the existence of an association between media multitasking and distractibility in laboratory tasks of information processing.

     

Decision-making,cognitive functions,impulsivity, and media multitasking expectancies in high versus low media multitaskers

In several studies, individuals who reported to frequently multitask with different media displayed reduced cognitive performance, for example in fluid intelligence and executive functioning. These cognitive functions are relevant for making advantageous decisions under both objective risk (requiring reflection and strategical planning) and ambiguous risk (requiring learning from feedback). Thus, compared to low media multitaskers (LMMs), high media multitaskers (HMMs) may perform worse in both types of decision situations. The current study investigated HMMs and LMMs in a laboratory setting with the Game of Dice Task (GDT; objective risk), the Iowa Gambling Task (IGT; ambiguous risk), various tests quantifying cognitive functions (logical reasoning, working memory, information processing, general executive functions), and self-report measures of impulsivity, media multitasking expectancies, and problematic Internet use. From 182 participants, 25 HMMs and 19 LMMs were identified using the Media Multitasking Index. Results show that HMMs compared to LMMs performed weaker on the IGT but not on the GDT. Furthermore, HMMs had slightly decreased performance in tests of logical reasoning and working memory capacity. HMMs tended to increased information processing speed but this difference was not significant. Furthermore, HMMs have more positive expectancies regarding media multitasking and reported higher tendencies toward problematic Internet use. HMMs and LMMs did not differ significantly with respect to impulsivity and executive functions. The results give a first hint that HMMs may have difficulties in decision-making under ambiguous but not under objective risk. HMMs may be more prone to errors in tasks that require feedback processing. However, HMMs appear not to be impaired in aspects of long-term strategic decision-making.

     

Working memory, fluid intelligence, and impulsiveness in heavy media multitaskers

Ophir, Nass, and Wagner (Proceedings of the National Association of Sciences 106:15583–15587, 2009) reported that individuals who routinely engage in multiple forms of media use are actually worse at multitasking, possibly due to difficulties in ignoring irrelevant stimuli, from both external sources and internal representations in memory. Using the media multitasking index (MMI) developed by Ophir et al., we identified heavy media multitaskers (HMMs) and light media multitaskers (LMMs) and tested them on measures of attention, working memory, task switching, and fluid intelligence, as well as self-reported impulsivity and self-control. We found that people who reported engaging in heavy amounts of media multitasking reported being more impulsive and performed more poorly on measures of fluid intelligence than did those who did not frequently engage in media multitasking. However, we could find no evidence to support the contention that HMMs are worse in a multitasking situation such as task switching or that they show any deficits in dealing with irrelevant or distracting information, as compared with LMMs.     

Correction to: Cognitive control in media multitaskers: Two replication studies and a meta-Analysis

Attention, Perception, & Psychophysics - In the original article, the number of HMMs and LMMs who took part in the first study was reported to have been 13and 10, respectively (p. 2624).     

Distractor selection ratios

A latent variable representation for multiple-choice item and option characteristic curves is presented. Under standard assumptions of conditional independence of item responses and monotonicity of item characteristic curves, a criterion for distractors is proposed based on distractor selection ratios. A connection is made between the proposed criterion and the theory of individual choice behavior, providing new insight. The main results allow for the testing of the criterion from observable data without first specifying a parametric form for the characteristic curves. A series of examples apply the method.     

预搜索过滤分心物的机制

如果先呈现若干分心物,然后添加靶子与其他分心物,那么就会改善搜索——预搜索效应。对于过滤分心物的潜在机制,研究者相继提出了主动抑制说、突然呈现说与时间分离说等理论。这些理论都有其合理的一面,能解释一些特定的实验现象,但任何单一机制都无法解释所有的实验现象。文章提出,未来的研究应该整合已有的实验现象与理论,系统考察旧客体与新客体的作用,重点整合抑制说与突现说,它们可能是一个连续体的两端     

Distractor strength and selective attention in picture-naming performance

Whereas it has long been assumed that competition plays a role in lexical selection in word production (e.g., Levelt, Roelofs, & Meyer, 1999), recently Finkbeiner and Caramazza (2006) argued against the competition assumption on the basis of their observation that visible distractors yield semantic interference in picture naming, whereas masked distractors yield semantic facilitation. We examined an alternative account of these findings that preserves the competition assumption. According to this account, the interference and facilitation effects of distractor words reflect whether or not distractors are strong enough to exceed a threshold for entering the competition process. We report two experiments in which distractor strength was manipulated by means of coactivation and visibility. Naming performance was assessed in terms of mean response time (RT) and RT distributions. In Experiment 1, with low coactivation, semantic facilitation was obtained from clearly visible distractors, whereas poorly visible distractors yielded no semantic effect. In Experiment 2, with high coactivation, semantic interference was obtained from both clearly and poorly visible distractors. These findings support the competition threshold account of the polarity of semantic effects in naming.     

Distractor devaluation requires visual working memory

Visual stimuli seen previously as distractors in a visual search task are subsequently evaluated more negatively than those seen as targets. An attentional inhibition account for this distractor-devaluation effect posits that associative links between attentional inhibition and to-be-ignored stimuli are established during search, stored, and then later reinstantiated, implying that distractor devaluation may require visual working memory (WM) resources. To assess this, we measured distractor devaluation with and without a concurrent visual WM load. Participants viewed a memory array, performed a simple search task, evaluated one of the search items (or a novel item), and then viewed a memory test array. Although distractor devaluation was observed with low (and no) WM load, it was absent when WM load was increased. This result supports the notions that active association of current attentional states with stimuli requires WM and that memory for these associations plays a role in affective response.     

视觉搜索中的情绪干扰项预习效应

干扰项预习效应是视觉搜索的试次间效应, 反映了过去不成功的搜索经验对注意的抑制。本研究中, 被试对情绪材料进行视觉搜索时, 同一个画面中的刺激的情绪效价可能一致, 也可能存在一个效价与众不同的靶子。实验任务是要求被试找到该靶子, 并对它的非情绪特征进行辨别反应。本研究包括3个实验, 分别采用情绪面孔的照片、情绪性动物图片、情绪性动物示意图, 均发现了情绪干扰项预习效应。也就是说, 当先呈现无靶子的试次再呈现有靶子的试次, 且有靶子的试次中干扰项的效价与之前无靶子试次中的刺激的效价一致时, 被试的反应要比靶子的效价与之前无靶子试次中刺激效价一致时更快。这些结果表明, 选择性注意系统可以利用以往的情绪信息引导注意的分配, 使当前注意偏离那些曾经搜索过但没有找到靶子的情绪特征, 而且这些情绪信息可能是由人脸表达的, 也可能是由于人以外的因素表达的。这些结果体现了情绪与认知的交互作用, 尤其是个体对情绪的已有经验对视觉选择注意的引导作用。     

Distractor repetitions retrieve previous responses to targets

Response retrieval theories assume that stimuli and responses become integrated into “event files” (Hommel, 1998 Hommel, B. 1998. Event files: Evidence for automatic integration of stimulus–response episodes. Visual Cognition, 5: 183–216. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) in memory so that a second encounter with a specific stimulus automatically retrieves the response that was previously associated with this stimulus. In this article, we tested a specific prediction of a recent variant of stimulus retrieval theories as introduced by Rothermund, Wentura, and De Houwer (2005) Rothermund, K., Wentura, D. and De Houwer, J. 2005. Retrieval of incidental stimulus–response associations as a source of negative priming: Evidence from task switching studies. Journal of Experimental Psychology: Learning, Memory, and Cognition, 31: 482–495. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]: In selection tasks where target stimuli are accompanied by distractors, responses to target stimuli are automatically bound to distractor stimuli as well; repeating the distractor should retrieve the response to the target that formerly accompanied the distractor. In three experiments we confirmed this prediction: Distractor repetition facilitated responding in the probe in the case of response repetition whereas repeating the distractor delayed responding in the case of response change.     

Distractor repetitions retrieve previous responses to targets

Response retrieval theories assume that stimuli and responses become integrated into “event files” (Hommel, 1998) in memory so that a second encounter with a specific stimulus automatically retrieves the response that was previously associated with this stimulus. In this article, we tested a specific prediction of a recent variant of stimulus retrieval theories as introduced by Rothermund, Wentura, and De Houwer (2005): In selection tasks where target stimuli are accompanied by distractors, responses to target stimuli are automatically bound to distractor stimuli as well; repeating the distractor should retrieve the response to the target that formerly accompanied the distractor. In three experiments we confirmed this prediction: Distractor repetition facilitated responding in the probe in the case of response repetition whereas repeating the distractor delayed responding in the case of response change.     

Distractor interference during smooth pursuit eye movements

When 2 targets for pursuit eye movements move in different directions, the eye velocity follows the vector average (S. G. Lisberger & V. P. Ferrera, 1997). The present study investigates the mechanisms of target selection when observers are instructed to follow a predefined horizontal target and to ignore a moving distractor stimulus. Results show that at 140 ms after distractor onset, horizontal eye velocity is decreased by about 25%. Vertical eye velocity increases or decreases by 1 degrees /s in the direction opposite from the distractor. This deviation varies in size with distractor direction, velocity, and contrast. The effect was present during the initiation and steady-state tracking phase of pursuit but only when the observer had prior information about target motion. Neither vector averaging nor winner-take-all models could predict the response to a moving to-be-ignored distractor during steady-state tracking of a predefined target. The contributions of perceptual mislocalization and spatial attention to the vertical deviation in pursuit are discussed.     

Distractor ratio and grouping processes in visual conjunction search.

According to feature integration theory, conjunction search is conducted via a serial self-terminating search. However, effects attributed to search processes operating on the entire display may actually reflect search restricted to elements defined by a single feature. In experiment 1 this question is addressed in a reaction-time (RT) paradigm by varying distractor ratios within an array of fixed size. For trials in which the target was present in the array, RT functions were roughly symmetric, the shortest RTs being for extreme distractor ratios, and the longest RTs being for arrays in which there were an equal number of each distractor type. This result is superficially consistent with Zohary and Hochstein's interpretation that subjects search for only one distractor type and are able to switch search strategy from trial to trial. However, negative-trial data from experiment 1 case doubt on this interpretation. In experiment 2 the possible role of 'pop out' and of distractor grouping in visual conjunction search is investigated. Results of experiment 2 suggest that grouping may play a more important role than does distractor ratio, and point to the importance of the spatial layout of the target and of the distractor elements in visual conjunction search. Results of experiment 2 also provide clear evidence that groups of spatially adjacent homogeneous elements may be processed as a unit.     

Distractor interference stays constant despite variation in working memory load

Previous studies have shown that working memory (WM) plays an important role in selective attention, so that high WM load leads to inefficient distractor inhibition, in comparison with low WM load. In the present study, we examined the effect of WM on distractor processing while the extent of attentional focus was held constant. Our results show that WM load affected distractor processing only when it was positively correlated with the extent of attentional focus. When the latter was held constant, the effect of WM became negligible. Furthermore, when low WM load was paired with a wide attentional focus and high WM load was matched with a narrow attentional focus, greater distractor processing was found when the WM load was low than when it was high. These results suggest that efficient distractor inhibition may require only minimal WM resources and that the effect of WM on distractor processing is more complex than has previously been assumed.     

Distractor eccentricity and its effect on selective attention

Previous research has shown conflicting results regarding the effect of distractor eccentricity on selective attention. The present study examines the relationship between a distractor's retinal location and participants' response latencies to a target while holding constant the distribution of attention. In three experiments, the participants searched for a target among several distractors. The retinal location of the critical distractor was manipulated so that it was at either a central or a peripheral location. The results show that all else being equal, an incompatible distractor causes more interference at a peripheral location than at a central location. This distractor eccentricity effect suggests that the visual system can overcome the default bias in the distribution of attention that favors a central stimulus.     

Distractor effects during processing of words under load

The perceptual load model of attention (Lavie, 1995) suggests that processing of irrelevant distractors depends on the extent to which a relevant task engages full perceptual capacity. Word recognition models suggest that letter perception is facilitated in words relative to nonwords. These models led us to hypothesize that increasing the number of letters would increase perceptual load more for nonwords than for words, and thus would be more likely to exhaust capacity and eliminate distractor processing for nonwords than for words. In support of this hypothesis, we found that increasing the number of search letters increases RTs more for nonwords than for words and only reduces distractor interference for nonwords. Thus, although readers process words more efficiently than nonwords, they also become more prone to distraction when processing words.     

Distractor interference in selective reaching: dissociating distance and grouping effects

In the present experiment, the authors sought to differentiate between a distance and a grouping explanation for the symmetric versus asymmetric patterns of distractor interference in selective reaching. Participants (N = 16) pointed to a green target that appeared either with or without a red distractor. Target-distractor separation was manipulated within an array of 5 closely grouped stimulus boxes, and distractor interference (difference in performance between trials with and trials without a distractor) was measured in reaction time, movement time, percentage errors, and movement endpoints. Small distances (5 mm) between target and distractor yielded a symmetric pattern of interference, whereas large distances (20 mm) yielded an asymmetric pattern, with more interference from near than from far distractors. Those findings support the distance account of distractor interference and refute the grouping account.     

Distractor Interference in Selective Reaching: Dissociating Distance and Grouping Effects

In the present experiment, the authors sought to differentiate between a distance and a grouping explanation for the symmetric versus asymmetric patterns of distractor interference in selective reaching. Participants (N = 16) pointed to a green target that appeared either with or without a red distractor. Target-distractor separation was manipulated within an array of 5 closely grouped stimulus boxes, and distractor interference (difference in performance between trials with and trials without a distractor) was measured in reaction time, movement time, percentage errors, and movement endpoints. Small distances (5 mm) between target and distractor yielded a symmetric pattern of interference, whereas large distances (20 mm) yielded an asymmetric pattern, with more interference from near than from far distractors. Those findings support the distance account of distractor interference and refute the grouping account.     

Distractor effect on the latent inhibition of conditioned flavor aversion in rats

Using a conditioned flavor aversion procedure with rats as subjects, the effect of the addition of a distractor stimulus on the magnitude of the latent inhibition effect was examined. Experiment 1 showed that latent inhibition to vinegar was attenuated by the addition of sucrose during preexposure. On the other hand, sucrose added during conditioning to vinegar did not attenuate latent inhibition. It was also found that the degree of latent inhibition to the vinegar-sucrose compound solution was less when vinegar alone was preexposed (i.e., when sucrose was added only during conditioning) than when the compound solution was preexposed (i.e., when sucrose was added both during preexposure and during conditioning). Experiment 2 gave similar results but with sucrose assigned as the target flavor and vinegar as the distractor. These findings are in full agreement with the generalization decrement account of latent inhibition.