Using Dichotic Listening to Study Bottom-up and Top-down Processing in Children and Adults

The study examined top-down attention modulation of bottom-up processing in children and adults under conditions of varying bottom-up stimulus demands. Voiced and unvoiced consonant-vowel syllables were used in a dichotic-listening situation to manipulate the strength of the bottom-up stimulus-driven right ear advantage when subjects were instructed to focus attention on, and report, either the left or right ear stimulus. We predicted that children would differ from adults in their ability to use attention to modulate a lateralized ear advantage, and particularly when there was a conflict between the direction of the bottom-up ear advantage and the direction of the top-down attention instruction. Thirty children and 30 adults were presented with dichotic presentations of consonant-vowel syllables. The results showed that the voicing manipulation affected the strength of the ear advantage, and that the children performed significantly below the adults when the voicing parameter caused a strong conflict between bottom-up and top-down processing. Thus, children seem to lack the cognitive flexibility necessary to modulate a stimulus-driven bottom-up ear advantage, particularly in situations where right ear advantage (REA) is enhanced by the acoustic properties of the stimuli and attentional demands require a left ear shift. It is suggested that varying the stimulus demands in a dichotic-listening situation may be a novel way to study cognitive development.     

Active Listening Delays Attentional Disengagement and Saccadic Eye Movements

Successful goal-directed visual behavior depends on efficient disengagement of attention. Attention must be withdrawn from its current focus before being redeployed to a new object or internal process. Previous research has demonstrated that occupying cognitive processes with a secondary cellular phone conversation impairs attentional functioning and driving behavior. For example, attentional processing is significantly impacted by concurrent cell phone use, resulting in decreased explicit memory for on-road information. Here, we examined the impact of a critical component of cell-phone use—active listening—on the effectiveness of attentional disengagement. In the gap task—a saccadic manipulation of attentional disengagement—we measured saccade latencies while participants performed a secondary active listening task. Saccadic latencies significantly increased under an active listening load only when attention needed to be disengaged, indicating that active listening delays a disengagement operation. Simple dual-task interference did not account for the observed results. Rather, active cognitive engagement is required for measurable disengagement slowing to be observed. These results have implications for investigations of attention, gaze behavior, and distracted driving. Secondary tasks such as active listening or cell-phone conversations can have wide-ranging impacts on cognitive functioning, potentially impairing relatively elementary operations of attentional function, including disengagement.     

Focused and Nonfocused Attention in Verbal and Emotional Dichotic Listening: An FMRI Study

Functional magnetic resonance imaging (fMRI) was used to identify cortical regions which are involved in two dichotic listening tasks. During one task the subjects were required to allocate attention to both ears and to detect a specific target word (phonetic task), while during a second task the subjects were required to detect a specific emotional tone (emotional task). During three attentional conditions of each task, the subjects were required to focus attention to the right (FR) or left ear (FL), while during a third condition subjects were required to allocate attention to both ears simultaneously. In 11 right-handed male subjects, these dichotic listening tasks evoked strong activations in a temporofrontal network involving auditory cortices located in the temporal lobe and prefrontal brain regions. Hemodynamic responses were measured in the following regions of interest: Heschl's gyrus (HG), the planum polare (PP), the planum temporale (PT), the anterior superior temporal sulcus (aSTS), the posterior superior temporal sulcus (pSTS), and the inferior frontal gyrus region (IFG) of both hemispheres. The following findings were obtained: (1) the degree of activation in HG and PP depends on the direction of attention. In particular it was found that selectively attending to right-ear input led to increased activity specifically in the left HG and PP and attention to left ear input increased right-sided activity in these structures; (2) hemodynamic responses in the PT, aSTS, pSTS, and IFG were not modulated by the different focused-attention conditions; (3) hemodynamic responses in HG and PP in the nonforced conditions were the sum activation of the forced conditions; (4) there was no general difference between the phonetic and emotion tasks in terms of hemodynamic responses; (5) hemodynamic responses in the PT and pSTS were strongly left-lateralized, reflecting the specialization of these brain regions for language processing. These findings are discussed in the context of current theories of hemispheric specialization.     

Functional Lateralization of the Perception of Norwegian Word Tones - Evidence from a Dichotic Listening Experiment

The present paper addresses the question of the functional lateralization of the ability to perceive the tonal distinctions in tone languages. Dichotic listening experiments and investigations of the brain-damaged population have indicated that the left hemisphere is more active than the right in the perception of tone in East Asian tone languages like Mandarin Chinese and Thai. Two dichotic listening experiments involving speakers of Norwegian, a language with an opposition of two tones, have demonstrated a right-ear superiority in the perception of the tonal distinction, indicating left-hemisphere lateralization of the ability to perceive tonal distinctions in Norwegian as well as in the East Asian tone languages that have been previously investigated.     

The Role of Dichotic Listening Performance and Tasks of Executive Functions in Reading Impairment: A Discriminant Function Analysis

This study focused on the role of dichotic listening performance for the identification of reading impaired subtypes. Dichotic listening (DL), using verbal stimuli, has shown to be a valid measure of language lateralization. Usually, lateralization is estimated from the proportion of right ear over left ear accuracy during a free recall test procedure. However, it has been suggested that a more accurate estimate of laterality can be obtained by using a directed attention procedure. A sample of 43 reading disabled children of whom 18 showed signs of impaired language comprehension skills and 25 without language comprehension impairments, were compared to 20 age, and gender, matched controls on dichotic listening performance in both an unbiased free recall task and in a directed attention task using consonant-vowel syllables as dichotic stimuli. A laterality index was calculated for left and right ear stimuli reported during both the free recall condition and the attended ear-scores for the two directed attention conditions. Although both DL procedures yielded significant group differences, with a lower laterality score for the reading disabled compared to the controls, there was no main effect of DL-procedure or group × procedure interaction. Taken alone, DL performance could correctly classify 42% of the reading impaired samples, but together with other measures of executive functions, discriminant function analyses yielded 90.74% accuracy in classifying reading impaired children. The result indicates that DL together with tests of executive functions are valuable tools for assessment of reading impaired subjects.     

Psychometric and Behavioral Measures of Central Auditory Function: The Relationship Between Dichotic Listening and Digit Span Tasks

We hypothesized that the Digit Span (DS) subtest and component tasks (Wechsler, 1991) would show strong relationships with a dichotic listening test (Musiek, 1983). In two sets of archival clinical data (N = 74 and N = 51) we demonstrated that: (a) individuals with central auditory deficits had lower DS scores, F(1, 72) = 7.34, p = .008; η² = .09; and (b) left-ear dichotic deficits impacted forward span, F(2, 48) = 8.45, p = .001. Right-ear dichotic listening performance also accounted for significant variance in digit forward span (R ² = 0.17, p = .003). While limited in scope, the studies conclude that forward but not reverse span performance is strongly related to dichotic listening, and can serve as a marker for possible central auditory deficits.     

Effects of Attentional Focus on Skilled Performance in Golf

Wulf and colleagues (e.g., Wulf, Lauterbach, & Toole, 1999 Wulf, G., Lauterbach, B. and Toole, T. 1999. The learning advantages of an external focus of attention in golf. Research Quarterly for Exercise and Sport, 70: 1219–126.  [Google Scholar]) have demonstrated that the adoption of an external focus of attention is preferable for the learning of complex motor tasks. The present investigation extends the attention focus literature in two ways: (a) it compared the effectiveness of three different foci (internal, proximal external, and distal external) in a sample of skilled performers in a naturalistic environment, and (b) it examined the use of attentional foci under conditions of anxiety. Thirty-three skilled male golfers were assigned to one of three attentional focus groups and completed five blocks of ten pitch shots, three in neutral conditions and two in anxiety conditions. Results from two separate mixed model analyses of variance (ANOVAs) indicated that regardless of anxiety condition, those assigned to a distal external focus of attention performed most accurately (p < 0.05), whereas assignment to an internal focus of attention was associated with the least accurate performance (p < 0.05). Findings offer support for the constrained action hypothesis and point to the importance of skilled performers adopting a distal external focus, especially in competition.     

Dichotic listening pattern in conduction aphasia

This paper reports a finding of hemispheric brain asymmetry for speech in short-gestation infants (mean gestational age = 36 weeks). Using a new measure—degree of reduction in limb tremors following exposure to speech stimuli compared to two control groups, one hearing orchestral music, the other no patterned stimuli—we found that speech disproportionately affected right limb movements. It is not clear whether the effect is due to asymmetries in cortical or subcortical processing. This provides evidence against the notion that brain specialization for language functions necessarily appears over time; rather, specialization for some functions (e.g., speech reception) must be present at birth.     

焦虑和抑郁对正负性注意偏向的影响：注意控制的中介作用

采用状态-特质焦虑量表、流调抑郁量表、注意控制量表和正负性信息注意量表,对481名在校大学生进行调查研究,考察了焦虑、抑郁对注意偏向的影响,并探讨了注意控制在其中的中介作用。研究发现：（1）正性注意偏向与注意控制呈正相关,与状态焦虑、特质焦虑和流调抑郁呈负相关;负性注意偏向与注意控制呈负相关,与状态焦虑、特质焦虑和流调抑郁呈正相关。（2）特质焦虑、注意集中、注意转移可显著预测正性注意偏向,状态焦虑、流调抑郁和注意集中则显著预测负性注意偏向。（3）注意转移和注意集中中介了状态焦虑、特质焦虑、流调抑郁和正、负性注意偏向间的关系。研究提示注意控制是一个重要的保护性因素,可缓解或消除焦虑和抑郁对注意偏向的负面影响。     

Dichotic perception and laterality in neonates

Groups of 4-day-old neonates were tested for dichotic discrimination and ear differences with the High-Amplitude-Sucking procedure. In the first experiment, dichotic speech discrimination was attested by comparison with a control group. Furthermore, among those subjects who showed a substantial recovery of sucking response at least after one of the two syllable changes, it was observed that significantly more subjects manifested a stronger reaction to a right-ear change than to a left-ear change. In the second experiment, 4-day-old neonates were tested on syllable and music timbre discrimination. The significant Stimulus Type x Ear interaction observed suggests perceptual asymmetries indicative of very precocious brain specialization.     

注意负荷对内隐序列学习的影响研究

运用次级任务研究范式,采用符号计数的次级任务和歧义序列中的次级条件序列,将内隐序列学习分为单任务组和双任务组,统一在单任务条件下测试。结果发现:(1)两组被试内隐学习成绩差异不显著;(2)双任务组被试在学习组块和测试组块的内隐学习差异也不显著。结果进一步支持了在次级任务占用注意资源的条件下内隐学习仍然可以正常地获得、内隐序列学习不受注意负荷影响的观点。     

Dichotic and bisensory grouping effects

The relationship between the Gray and Wedderburn effect, the channel alternation effect and the class alternation effect was studied in dichotic and bisensory experiments using physically and semantically distinguishable word classes. With dichotic presentation all three effects were found to occur, but with bisensory presentation neither the Gray and Wedderburn effect nor the class alternation effect was detected. There were no significant differences between physically and semantically based grouping. The present investigation provides support for Broadbent's claim that the Gray and Wedderburn effect depends on the occurrence of the class alternation effect. The various dichotic and bisensory grouping effects are explicable in terms of selection by modality-specific processing systems.     

Dichotic testing of cerebral dominance in stutterers

Matched groups of right-handed male stutterers and controls received dichotic presentations of CVs and melodies on two occasions. Right ear advantages were obtained for CVs and left ear advantages for melodies, without significant differences between groups. However, a significantly greater number of stutterers than controls consistently failed to show the expected ear laterality for either type of material.     

自尊对情绪面孔注意偏向的影响

研究表明低自尊个体对负性信息表现出高度的警觉和关注,而高自尊个体相对来说注意积极地方面,但并未表现明显偏向。为了精确记录注意选择神经加工时间进程,进一步从电生理学角度对低自尊个体的负性注意偏向进行探讨,本研究运用事件相关电位（ERP）技术对不同自尊个体在点-探测任务过程中的注意偏向进行研究。实验一以129名在校大学生作为被试,以大学生面孔情绪图片（高兴、悲伤和中性）作为实验材料,结果发现,高低自尊个体之间没有出现注意偏向的差异。实验二以实验一筛选出的30名高低自尊个体作为被试,选择了更具负性情绪唤醒的愤怒图片作为实验材料（高兴、愤怒和中性）,行为数据结果发现,两组被试都没有出现注意偏向,相反,无论是在高兴面孔条件下还是在愤怒面孔条件下,低自尊个体的反应时都快于高自尊个体;电生理学数据结果发现,在低自尊个体中,在两种情绪面孔条件下,有效线索的P1峰值显著高于无效线索,而无效线索的N2pc峰值显著高于有效线索。电生理学数据表明,无论是负性的还是正性的情绪性的信息都能引起低自尊个体的更多注意,表明低自尊个体更容易受到情绪性信息的影响。     

Dichotic listening and left-right confusion

The present study examined the relationship between individual differences in dichotic listening (DL) and the susceptibility to left-right confusion (LRC). Thirty-six men and 59 women completed a consonant-vowel DL test, a behavioral LRC task, and an LRC self-rating questionnaire. Significant negative correlations between overall DL accuracy and LRC rates in men (behavioral task) and self-ratings in women, indicated that the more participants struggled with left-right discrimination, the fewer DL syllables they reported correctly. However, there was no relationship between LRC and the typical right ear advantage. Thus, there is a sex- and task-dependent relationship between LRC and overall DL accuracy, but not between LRC and ear asymmetry. It is concluded that (a) atypical ear asymmetries, as in certain clinical populations, cannot be explained by associated deficits in left-right discrimination, and (b) LRC can negatively affect task performance, even when participants do not have to make explicit "left" versus "right" decisions.     

Effects of Training Reflective Listening in a Corporate Setting

A communication skills training of insurance company employees was devised and evaluated. Study 1 compared trained and untrained employees on their Reflective listening (RL; Rogers, 1951) skills before and after a 16-hr training, as they conversed with a confederate who rated them, and their responses were categorized. In a follow-up Study 2, some of the employees audiotaped conversations with customers, and their responses were categorized as well. In a validation Study 3, students rated conversations by employees who used more or less RL. Results showed that training increased RL, and that the skills were subsequently transferred to an authentic setting. Results did not show that trained employees were evaluated differently than untrained. Implications of the results are discussed.     

注意偏向训练：起源、效果与机制

近年来注意偏向被证明是一些心理疾病产生、维持和复发的原因。因此, 注意偏向训练成为一种前景性的治疗方法, 对低自尊、焦虑障碍、物质成瘾有良好的干预效果。它可能作用于注意的晚期加工阶段, 通过调节 “自上而下”的注意系统来改变相关症状。干预效果的条件、机制与神经机制的探索应成为今后的研究方向。     

Dichotic backward masking of complex sounds

In the first experiment subjects identified a consonant-vowel syllable presented dichotically with a known contralateral masking sound at a stimulus onset asynchrony of ± 60 msec. When the mask followed the target syllable, perception of place of articulation of the consonant was impaired more when the mask was a different consonant-vowel syllable than when it was either a steady-state vowel or a non-speech timbre. Perception was disturbed less when the mask preceded the target, and the amount of disruption was independent of which mask was used. Greater backward than forward masking was also found in the second experiment for the identification of complex sounds which differed in an initial change in pitch. These experiments suggest that the extraction of complex auditory features from a target can be disrupted by the subsequent contralateral presentation of a sound sharing certain features with the target.     

Attentional resolution

Attention can enhance selectively the visual information processing of particular locations or objects. Recent studies have shown that this enhancement has limited spatial resolution, the smallest regions that can be isolated by attention are much coarser than the smallest details that can be resolved by vision. Multiple similar objects spaced more finely than the limit of attentional resolution cannot be individuated for further processing and can only be perceived as a grouped texture. As a result, at any given time, only part of the spatial and temporal information registered by the early sensory systems is available to conscious perception. It is likely that attentional resolution is limited at a stage beyond V1 and that it has a finer grain in the lower visual field than in the upper field. The spatial aperture of attention is elongated along the radial axis relative to fixation. The briefest temporal window of attention is also much broader than visual temporal resolution. Many perceptual phenomena related to rapid serial visual presentation may reflect the limited temporal resolution of attention.