Event-related potential and behavioral measures of attention in 5-, 7-, and 9-year-olds

In 2 experiments, the development of auditory selective attention in children was assessed. The participants, aged 5, 7, and 9 years, responded to target stimuli in the left ear for 1 series (ignoring the standard stimuli) and in the right ear for the other series. In Experiment 1, event-related potentials (ERPs) evoked by the auditory stimuli were recorded from frontal, central, and parietal sites. The 9-year-olds showed a greater processing negativity (Nd) to the attended channel compared with the 5-year-olds. Both 7- and 9-year-olds showed significantly larger amplitudes for the P3 component of ERPs in the attended vs. ignored condition. Behaviorally, the 5-year-olds made fewer hits and more false alarms than did older children, and the 9-year-olds made significantly more false alarms than did the 7-year-olds. The results of Experiment 2 showed that the detriment in the performance of the 9-year-olds was a result of task parameters. The inability of 5-year-olds to attend selectively appears to involve problems with the inhibition of the processing of irrelevant information and with selection of the correct response.     

跨感觉通路ERP注意成分的研究

采用提高了非注意纯度的“跨通路延迟反应”实验模式,研究跨通路注意的事件相关电位（ＥＲＰ）成分,以注意ＥＲＰ减去非注意ＥＲＰ的早期差异负波（Ｎｄ１）为主要分析对象。被试者为１２名青年正常人。结果发现：①听觉偏差刺激、视觉标准与偏差刺激皆在其特异性感觉区域的头皮部位,观察到注意引起Ｎ１波幅增大的现象。Ｎｄ１的起始时间与注意Ｎ１相同,而早于非注意Ｎ１,支持注意的早期选择学说;②听觉与视觉偏差刺激产生的Ｎｄ１最大峰分布在它们各自的初级感觉投射区,而标准刺激诱发的Ｎｄ１最大峰却分布于额部,表明跨通路选择性注意对偏差刺激的加工部位主要是通路特异性的,而对标准刺激的加工部位则主要是通路上的。作者据此针对选择性注意中长期争论问题进一步提出,注意的选择性发生时程的早晚可因刺激条件而异,信息过滤器的位置具有可塑性。     

Electrophysiological indices of brain activity to "the" in discourse

In a first experiment, we recorded event-related-potentials (ERPs) to "the" followed by meaningful words (Story) versus "the" followed by nonsense syllables (Nonse). Left and right lateral anterior positivities (LAPs) were seen from the onset of "the" up to 200 ms in both conditions. Later than 200 ms following the onset of "the", the left and right LAPs continued for "the" in the Story, but were replaced by a negativity in the Nonse Condition. In a second experiment, ERPs were recorded to "the" in the Story and Nonse contexts mixed together under two different task instructions (attend to the auditory stimuli versus ignore the auditory stimuli). The same pattern of findings as Experiment 1 were observed for the Story and Nonse contexts when the participants attended to the auditory stimuli. Ignoring the auditory stimuli led to an attenuation of the right LAP, supporting the hypothesis that it is an index of discourse processing.     

Auditory processing and cluttering in young children

This study examined the differences among scores on four tests of auditory processing of 6 children who clutter and 6 control subjects matched for age, sex, and grade. Scores on a consonant-vowel dichotic listening task indicated that directing the attention of the attended ear improved the percentage of correct responses for both groups of children. Those who clutter, however, showed a greater percentage of change during the directed right and left ear conditions. Cluttering children performed poorer on right and left competing conditions of the Staggered Spondaic Word Test. No differences were found between groups for the auditory attention task and the time-compressed speech task. Implications for processing of dichotic stimuli and diagnosis of children who clutter are discussed.     

Effects of Presentation Format and List Length on Children's False Memories

The effect of list length on children's false memories was investigated using list and story versions of the Deese/Roediger-McDermott procedure. Short (7 items) and long (14 items) sequences of semantic associates were presented to children aged 6, 8, and 10 years old either in lists or embedded within a story that emphasized the list theme. Subsequent tests of recognition memory revealed different effects of length for lists and stories across development. Longer lists produced more false alarms to critical lures for 8- and 10-year-olds only, and longer stories produced more false alarms to critical lures for 6-year-olds only. These results demonstrate that increasing the number of items presented at study increases false recognition for younger as well as older children when the theme of the items is made salient.     

Retrieval of Episodic Information From Memory: Comparisons Among 3- and 4-Year-Olds, 7- and 8-Year-Olds,and Adults

Young children's and adults' recall of episodic information was explored in 4 experiments. The task required participants to recall a target noun presented as the last item of a 4-noun string of related (either categorically or thematically) or unrelated words. Providing all 3 preceding nouns or a subset of them cued recall. Experiment 1 found that 7- and 8-year-old children's recall was better with pictures as opposed to text, and children showed performance equal to adults with thematically related pictorial stimuli. Using pictorial stimuli, Experiment 2 showed that the number of cues present at retrieval affected 7- and 8-year-olds' recall. Experiments 3 and 4 tested recall of episodic information in 3- and 4-year-olds using pictorial stimuli. The results suggested that young children also have access to episodic information in memory and the number of cues present at retrieval influenced recall. The findings are discussed in the context of children's memory for events.     

Auditory and visual differences in time perception? An investigation from a developmental perspective with neuropsychological tests

Adults and children (5- and 8-year-olds) performed a temporal bisection task with either auditory or visual signals and either a short (0.5-1.0s) or long (4.0-8.0s) duration range. Their working memory and attentional capacities were assessed by a series of neuropsychological tests administered in both the auditory and visual modalities. Results showed an age-related improvement in the ability to discriminate time regardless of the sensory modality and duration. However, this improvement was seen to occur more quickly for auditory signals than for visual signals and for short durations rather than for long durations. The younger children exhibited the poorest ability to discriminate time for long durations presented in the visual modality. Statistical analyses of the neuropsychological scores revealed that an increase in working memory and attentional capacities in the visuospatial modality was the best predictor of age-related changes in temporal bisection performance for both visual and auditory stimuli. In addition, the poorer time sensitivity for visual stimuli than for auditory stimuli, especially in the younger children, was explained by the fact that the temporal processing of visual stimuli requires more executive attention than that of auditory stimuli.     

Investigating the mechanisms of visually-evoked tactile sensations

When attempting to detect a near-threshold signal, participants often incorrectly report the presence of a signal, particularly when a stimulus in a different modality is presented. Here we investigated the effect of prior experience of bimodal visuotactile stimuli on the rate of falsely reported touches in the presence of a light. In Experiment 1, participants made more false alarms in light-present than light-absent trials, despite having no experience of the experimental visuotactile pairing. This suggests that light-evoked false alarms are a consequence of an existing association, rather than one learned during the experiment. In Experiment 2, we sought to manipulate the strength of the association through prior training, using supra-threshold tactile stimuli that were given a high or low association with the light. Both groups still exhibited an increased number of false alarms during light-present trials, however, the low association group made significantly fewer false alarms across conditions, and there was no corresponding group difference in the number of tactile stimuli correctly identified. Thus, while training did not affect the boosting of the tactile signal by the visual stimulus, the low association training affected perceptual decision-making more generally, leading to a lower number of illusory touch reports, independent of the light.     

Auditory orienting of attention: Effects of cues and verbal workload with children and adults

The use of tone cues has an improving effect on the auditory orienting of attention for children as for adults. Verbal cues, on the contrary, do not seem to orient attention as efficiently before the age of 9 years. However, several studies have reported inconsistent effects of orienting attention on ear asymmetries. Multiple factors are questioned, such as the role of verbal workload. Indeed, the semantic nature of the dichotic pairs and their load of processing may explain orienting of attention performance. Thus, by controlling for the role of verbal workload, the present experiment aimed to evaluate the development of capacities for the auditory orienting of attention. Right-handed, 6- to 12-year-olds and adults were recruited to complete either a tone cue or a verbal cue dichotic listening task in the identification of familiar words or nonsense words. A factorial design analysis of variance showed a significant right-ear advantage for all the participants and for all the types of stimuli. A major developmental effect was observed in which verbal cues played an important role: they allowed the 6- to 8-year-olds to improve their performance of identification in the left ear. These effects were taken as evidence of the implication of top-down processes in cognitive flexibility across development.     

Individual Differences in Arousal and Accessibility to Information in Memory

The authors conducted 9 experiments to test the hypothesis (S. Schwartz, 1975) that arousal influences the accessibility of information stored in memory. They investigated the relationship between arousal levels (as indexed by personality types) and the type of stimuli or cues presented during study or test. They predicted that low-arousal individuals (stable extroverted individuals in Experiments 1-3 and 5-9 and high-impulsive individuals in Experiment 4) would be influenced by semantic stimuli, whereas high-arousal individuals (neurotic introverted individuals in Experiments 1-3 and 5-9 and low-impulsive individuals in Experiment 4) would be influenced by physical (i.e., graphic, phonetic, or both) stimuli. They tested the arousal-accessibility hypothesis by using a variety of tasks including verbal discrimination, false recognition, cued recall, and paired associates. With the exception of the finding that stable extroverted participants performed better than neurotic introverted participants on an incidental associative-matching task (Experiment 3), the results from the verbal discrimination studies (1-5) did not support the hypothesis. In Experiment 6, the authors tested the hypothesis by using a false-recognition task. False alarms varied as a function of phonetic and semantic stimuli, but personality types were not differentially sensitive to the manipulation. The same was true for the cued-recall studies (Experiments 7 and 8); personality types were not differentially sensitive to the semantic and phonetic stimuli. Experiment 9 (paired-associate learning) was a replication of Schwartz's study. The authors found some support for the Schwartz hypothesis: Extraverted participants were adversely affected by semantic similarity. Overall, the findings did not provide much support for the arousal-accessability hypothesis.     

Effects of visual attentional load on low-level auditory scene analysis

The sharing of processing resources between the senses was investigated by examining the effects of visual task load on auditory event-related brain potentials (ERPs). In Experiment 1, participants completed both a zero-back and a one-back visual task while a tone pattern or a harmonic series was presented. N1 and P2 waves were modulated by visual task difficulty, but neither mismatch negativity (MMN) elicited by deviant stimuli from the tone pattern nor object-related negativity (ORN) elicited by mistuning from the harmonic series was affected. In Experiment 2, participants responded to identity (what) or location (where) in vision, while ignoring sounds alternating in either pitch (what) or location (where). Auditory ERP modulations were consistent with task difficulty, rather than with task specificity. In Experiment 3, we investigated auditory ERP generation under conditions of no visual task. The results are discussed with respect to a distinction between process-general (N1 and P2) and processspecific (MMN and ORN) auditory ERPs.     

Feature processing during high-rate auditory selective attention

Auditory event-related brain potentials (ERPs) and reaction times were, analyzed in a selective attention task in which subjects attended to tone pips presented at high rates-Xinterstimulua intervals [ISIs] of 40-200 msec). Subjects responded to infrequent target tones of a specified frequency (250 or 4000 Hz) and location (left or right ear) that were louder than otherwise identical tones presented randomly to the left and right ears. Negative difference (Nd) waves were isolated by subtracting ERPs to tones with no target features from ERPs to the same tones when they shared target location, frequency, or both frequency and location cues. Nd waves began 60-70 msec after tone onset and lasted until 252–350 msec after tone onset, even for tones with single attended cues. The duration of Nd waves exceeded the ISIs between successive tones, implying that several stimuli underwent concurrent analysis. Nd waves associated with frequency processing had scalp distributions different from those associated with location processing, implying that the features were analyzed in distinct cortical areas. Nd waves specific to auditory feature conjunction were isolated. These began at latencies of 110–120 msec, some 30-40 msec after the Nds to single features. The relative timing of the different Nd waves suggests that auditory feaure conjunction begins after a brief parallel analysis of individual features but before feature analysis is complete.     

Enhanced recognition and recall of new words in 7- and 12-year-olds following a period of offline consolidation

Recent studies of adults have found evidence for consolidation effects in the acquisition of novel words, but little is known about whether such effects are found developmentally. In two experiments, we familiarized children with novel nonwords (e.g., biscal) and tested their recognition and recall of these items. In Experiment 1, 7-year-olds were then retested on either the same day or the following day to examine changes in performance after a short delay compared with a longer delay that included sleep. Experiment 2 used two age groups (7- and 12-year-olds), with all participants being retested 24h later. The 12-year-olds accurately recognized the novel nonwords immediately after exposure, as did the 7-year-olds in Experiment 2 (but not in Experiment 1), suggesting generally good initial rates of learning. Experiment 1 revealed improved recognition of the novel nonwords after both short (3- to 4-h) and longer (24-h) delays. In contrast, recall was initially poor but showed improvements only when children were retested 24h later, not after a 3- to 4-h delay. Similar improvements were observed in both age groups despite better overall performance in 12-year-olds. We argue that children, like adults, exhibit offline consolidation effects on the formation of novel phonological representations.     

Story contexts increase susceptibility to the DRM illusion in 5-year-olds

False recognition in children aged 5, 8, and 11 years was investigated using the standard version of the Deese-Roediger-McDermott (DRM) procedure and an alternative version in which the DRM stimuli were embedded in stories designed to emphasize their overall theme. Relative to the 8- and 11-year-olds, the 5-year-olds falsely recognized fewer critical lures when the DRM stimuli were presented in lists, but falsely recognized more critical lures when the stimuli were presented in stories. Levels of false recognition in the 8- and 11-year-olds were not affected by study format. We argue that the story context enhanced the ability of the 5-year-olds to make inferences based on the theme of the DRM stimuli. The 5-year-olds then showed higher levels of false recognition than the older children owing to their inability to reject lure words consistent with the stories.     

Effects of temporal trial-by-trial cuing on early and late stages of auditory processing: Evidence from event-related potentials

Temporal-cuing studies show faster responding to stimuli at an attended versus unattended time point. Whether the mechanisms involved in this temporal orienting of attention are located early or late in the processing stream has not been answered unequivocally. To address this question, we measured event-related potentials in two versions of an auditory temporal cuing task: Stimuli at the uncued time point either required a response (Experiment 1) or did not (Experiment 2). In both tasks, attention was oriented to the cued time point, but attention could be selectively focused on the cued time point only in Experiment 2. In both experiments, temporal orienting was associated with a late positivity in the timerange of the P3. An early enhancement in the timerange of the auditory N1 was observed only in Experiment 2. Thus, temporal attention improves auditory processing at early sensory levels only when it can be focused selectively.     

加工水平对普通话与粤语记忆语言依赖效应的影响

通过两个实验,考察了加工水平对普通话和粤语记忆语言依赖效应的影响。实验1考察了在有意学习中的记忆语言依赖效应。结果表明,测验的语言环境对再认有重要影响。被试在粤语测验环境下对学习过的韩国语词再认反应时短,误报率却低,辨别力强,“记得”反应占优势。实验2考察了无意学习中的记忆语言依赖效应。结果表明,被试在粤语测验环境下,对评定过的韩国语词再认反应时短,误报率却高,辨别力差,但“记得”反应占优势;但在普通话测验环境下,对评定过的韩国语词再认反应时长,误报率却低,辨别力强,“知道”和“猜测”反应增加。整个研究表明,记忆的语言依赖效应在有意学习和无意学习中都存在,但有不同的趋势,表明加工水平是影响普通话和粤语记忆语言依赖效应的重要变量     

False memories in children and adults: age,distinctiveness, and subjective experience

This study investigated developmental trends associated with the Deese/Roediger-McDermott false-memory effect, the role of distinctive information in false-memory formation, and participants' subjective experience of true and false memories. Children (5- and 7-year-olds) and adults studied lists of semantically associated words. Half of the participants studied words alone, and half studied words accompanied by pictures. There were significant age differences in recall (5-year-olds evinced more false memories than did adults) but not in recognition of critical lures. Distinctive information reduced false memory for all age groups. Younger children provided with distinctive information, and older children and adults regardless of whether they viewed distinctive information, expressed higher levels of confidence in true than in false memories. Source attributions did not significantly differ between true and false memories. Implications for theories of false memory and memory development are discussed.     

Algorithms for processing spatial information

Pairs of stimuli taken from a psychometric measure of spatial aptitude were shown to 9-year-olds, 13-year-olds, and adults. The stimuli in pairs were (a) either identical or mirror images, and (b) presented in orientations that differed by 0-150 degrees. Individuals judged, as rapidly as possible, if the stimuli in a pair would be identical or mirror images if presented at the same orientation. In Experiment 1, in which the stimuli were letter-like characters, at all ages most persons solved the problems using an algorithm in which an individual encodes the stimuli in working memory, mentally rotates one stimulus to the orientation of the other, compares them to determine if they are identical, and responds. In Experiment 2, the stimuli were multielement flags; here, the modal algorithm for both 9- and 13-year-olds differed from the previously described algorithm in that if the comparison process revealed that the stimuli were dissimilar, individuals did not respond immediately, but continued processing until a self-imposed deadline was reached. Among adults, the modal algorithm was the same one used in Experiment 1. Results are discussed in terms of the roles of encoding in contributing to the use of a particular algorithm.