Auditory perception of dissonant polyrhythms

Although the ability of subjects to judge the duration of a temporal interval has been investigated using a variety of paradigms, most of the studies have used very short intervals ranging from a few hundred milliseconds to several seconds. Therefore, the purpose of the present study was to examine the psychophysical relationship between judged and actual durations of longer intervals ranging from months to years. In Experiment 1, college students were asked to estimate the ages of 12 major news events which had occurred during the previous 5 years. Analysis of median estimates of each item showed that subjects underestimated the ages of the oldest items and overestimated the ages of the most recent items. To determine whether this regression effect was due to a response bias or to the context effect produced by other items on the questionnaire, Experiments 2 and 3 systematically varied the range of allowable response alternatives and the age of the background items that formed the context in which the experimental items were judged. Although the range of allowable response alternatives had a significant effect upon the estimates, no evidence was obtained for an item context effect. The data are interpreted in terms of a memory-based hypothesis which suggests that the subjects were attempting to recall the time of occurrence of the items and then deriving elapsed time rather than directly judging duration.     

Interactions of speech and manual movement in a syncopated task

The present study examined interactions of speech production and finger-tapping movement, using a syncopated motor task with two movements in 10 male right-handed undergraduate students (M age = 21.0 yr.; SD = 1.4). On the syncopated task, participants were required to produce one movement exactly midway between two other movements (target interresponse interval: 250 msec.). They were divided into two groups, the tap-preceding group and speech-preceding group. The author observed that the right hand showed a more variable peak force and intertap interval than the left hand in the speech-preceding group, indicating an asymmetrical interference of two movements. On the other hand, the mean differences between onsets of speech and tapping movement were shorter than 250 msec. over all conditions (the shortest mean difference was 50 msec.), suggesting a mutual entrainment of two movements. An asymmetry of entrainment was observed in the speech-preceding group, in which speech production was more strongly entrained with movements of the right hand than with those of the left hand.     

Bimanual tapping of a syncopated rhythm reveals hemispheric preferences for relative movement frequencies

In bimanual multifrequency tapping, right-handers commonly use the right hand to tap the relatively higher rate and the left hand to tap the relatively lower rate. This could be due to hemispheric specializations for the processing of relative frequencies. An extension of the double-filtering-by-frequency theory to motor control proposes a left hemispheric specialization for the control of relatively high and a right hemispheric specialization for the control of relatively low tapping rates. We investigated timing variability and rhythmic accentuation in right handers tapping mono- and multifrequent bimanual rhythms to test the predictions of the double-filtering-by-frequency theory. Yet, hemispheric specializations for the processing of relative tapping rates could be masked by a left hemispheric dominance for the control of known sequences. Tapping was thus either performed in an overlearned quadruple meter (tap of the slow rhythm on the first auditory beat) or in a syncopated quadruple meter (tap of the slow rhythm on the fourth auditory beat). Independent of syncopation, the right hand outperformed the left hand in timing accuracy for fast tapping. A left hand timing benefit for slow tapping rates as predicted by the double-filtering-by-frequency theory was only found in the syncopated tapping group. This suggests a right hemisphere preference for the control of slow tapping rates when rhythms are not overlearned. Error rates indicate that overlearned rhythms represent hierarchically structured meters that are controlled by a single timer that could potentially reside in the left hemisphere.     

Understanding how speed affects performance of polyrhythms: transferring control as speed increases

Pianists (N = 9) memorized and performed polyrhythms over a range of speeds from 1 to 16 notes/s. Using several fingers of each hand to press the keys on a piano keyboard, they performed the 5:3 polyrhythm by playing "3s" with one hand simultaneously with "5s" in the other. All the participants were able to maintain overall tempos and rhythms to within 10% of target speeds despite increasing difficulty. Increasing speed led to a transfer of control at about 6 notes/s, with a modular system operating above that speed. The participants were also able to engage in timing coupling at all speeds, even when the hands belonged to different people.     

Rapid motor adaptations to subliminal frequency shifts during syncopated rhythmic sensorimotor synchronization

The synchronization of rhythmic arm movements to a syncopated metronome cue was studied in a step-change design whereby small tempo shifts were inserted at fixed time points into the metronome frequency. The cueing sequence involved three stimulus types: (1) target contact in synchrony with the metronome beats, (2) syncopated target contact midway in time between audible beats, and (3) syncopated target contact following either a +2% or -2% change in stimulus frequency. Analysis of normalized and aggregated data revealed that (1) during the syncopation condition the response period showed a rapid adaptation to the frequency-incremented stimulus period, (2) response period was less variable during syncopated movement, (3) mean synchronization error and variability, calculated during syncopation relative to the mathematical midpoint of the stimulus cycle, were reduced during syncopated movements, and (4) synchronization error following the frequency increment showed trends to return linearly to pre-increment values which was fully achieved in the -2% change condition only. The results suggest that frequency entrainment to stimulus period was possible during syncopated movement with the response and stimulus onsets 180 degrees out of phase. Most remarkably, 70-80% of the adaptation of the response period to the new stimulus period was immediately attained during the second half cycle of the syncopated movement. Finally, a mathematical model, based on recursion, was introduced that accurately modeled actual data as a function of the previous stimulus and response intervals and a weighted response of period error and synchronization error, which showed dominance of frequency entrainment over phase entrainment during rhythmic synchronization.     

The modification of auditory hallucinations

The ABAB withdrawal design was used to document the effectiveness of a behavioral treatment package in reducing the duration of auditory hallucinations of a chronically mentally ill inpatient. Results revealed clear functional control of the treatment package over the occurrence of the subject's auditory hallucinations during a 2-hr time period.     

Continuation of auditory frequency gradients across temporal breaks: The auditory Poggendorff

An auditory analog of the visual Poggendorff figure was constructed on the assumption that selected temporal variables in audition have parallels with selected spatial variables in vision. As with the visual Poggendorff, the extent of underestimation within the auditory analog is directly related to the slope of the signal and to the magnitude of the temporal gap being bridged. Some of the conditions which limit the existence region of the auditory Poggendorff are determined.     

The cognitive neuroscience of auditory distraction

We are often aware of the content of distracting sound, although typically remain unaware of the processes by which that sound is disruptive. Disruption can occur even when the sound is ignored and unrelated to the task being performed. In a recent major development, Gisselg?rd et al. have used positron emission tomography to reveal how distracting sounds recruit the involvement of dorsolateral prefrontal cortex.     

The importance of semantics in auditory representations

The purpose of the present study was to examine the nature of auditory representations by manipulating the semantic and physical relationships between auditory objects. On each trial, listeners heard a group of four simultaneous sounds for 1 sec, followed by 350 msec of noise, and then either the same sounds or three of the same plus a new one. Listeners completed a change-detection task and an object-encoding task. For change detection, listeners made a same-different judgment for the two groups of sounds. Object encoding was measured by presenting probe sounds that either were or were not present in the two groups. In Experiments 1 and 3, changing the target to an object that was acoustically different from but semantically the same as the original target resulted in more errors on both tasks than when the target changed to an acoustically and semantically different object. In Experiment 2, comparison of semantic and acoustic effects demonstrated that acoustics provide a weaker cue than semantics for both change detection and object encoding. The results suggest that listeners rely more on semantic information than on physical detail.)     

The role of loudness in auditory imagery

Four experiments studied characteristics of auditory images initiated by named but unheard sounds. The sounds varied in their loudness ratings. As the difference between the loudness ratings of the two sound phrases increased, the times to mentally equate the loudness of the two images increased, whereas the times to identify the louder (or softer) of the images decreased. Moreover, congruity effects were found in the comparative judgment task: Times were faster to identify the louder of two loud-rated stimuli than to judge the softer of the same two stimuli, and times were faster to identify the softer of the two soft-rated than two loud-rated stimuli. The loudness ratings did not always influence performance, however, for neither an image generation nor a reading task showed response times that varied with loudness ratings. These results suggest that sensory/perceptual components are optionally represented in auditory images. These components are included when appropriate to a given task. A control experiment showed that the results cannot be considered epiphenomenal.     

The fidelity of visual and auditory memory

Psychonomic Bulletin & Review - Recent studies show that recognition memory for pictures is consistently better than recognition memory for sounds. The purpose of this experiment was to compare...     

听觉警报失聪的认知因素

无意失聪是指当人们集中精神做事时,会忽略非预期的听觉刺激。这种现象在现实生活中普遍存在,它对航空和交通安全构成巨大威胁。研究者们发现高知觉和高认知负荷条件下个体会因认知资源有限导致无意失聪,且随着负荷增加,被忽略的听觉刺激诱发的早期（N100）和晚期（P300）神经活动有所减弱。这表明非预期听觉刺激可以进入晚期加工阶段,但其能否被感知可能取决于与工作记忆相关的额顶网络的抑制控制程度。而工作记忆容量及其负荷与无意失聪关系的现有研究结果之间还存在不一致性。未来研究可以将其范式和理论拓展到其他安全生产领域,并运用认知训练等方式规避无意失聪,从而减少人因失误。     

The remembering of auditory event durations.

Three experiments examined the incidental remembering of event durations. In each study, Ss engaged in an initial learning phase in which they performed a set of perceptual ratings on events for a varying number of trials. These events consisted of tonal sequences or ecological sounds that varied in their internal structure and ending. Ss were then given a surprise memory task in which they were asked to recognize the duration of each event (Experiments 1 and 3) or extrapolate its completion (Experiment 2). Results showed that in contrast to irregularly timed events, those filled with regularly timed or continuous pitch information yielded high levels of accuracy that increased with greater learning experience. In addition, durations marked by a nonarbitrary ending were more accurately remembered than those marked by an arbitrary ending which, in fact, were misremembered as shorter than their actual duration. These findings are discussed in terms of an approach that emphasizes the role of event structure on perceiving and remembering activities.     

The role of melodic and temporal cues in perceiving musical meter

A number of different cues allow listeners to perceive musical meter. Three experiments examined effects of melodic and temporal accents on perceived meter in excerpts from folk songs scored in 6/8 or 3/4 meter. Participants matched excerpts with 1 of 2 metrical drum accompaniments. Melodic accents included contour change, melodic leaps, registral extreme, melodic repetition, and harmonic rhythm. Two experiments with isochronous melodies showed that contour change and melodic repetition predicted judgments. For longer melodies in the 2nd experiment, variables predicted judgments best at the beginning of excerpts. The final experiment, with rhythmically varied melodies, showed that temporal accents, tempo, and contour change were the strongest predictors of meter. The authors' findings suggest that listeners combine multiple melodic and temporal features to perceive musical meter.     

The effect of continuity on auditory stream segregation

Condition, transitions between tones were abrupt; in the “ramped” condition, successive tones were connected by frequency glides. In the “semiramped” condition, there were partial glides in frequency (as in speech). “Discrete” sequences were most likely to split perceptually into high and low streams, making order discriminations difficult. The “ramped” condition was least likely to split, and order perception was easiest. Results for the “semiramped” condition were intermediate. The discussion relates these findings to the acoustic properties of speech and to the process of auditory stream formation.     

The effects of divided attention on auditory priming

Traditional theorizing stresses the importance of attentional state during encoding for later memory, based primarily on research with explicit memory. Recent research has begun to investigate the role of attention in implicit memory but has focused almost exclusively on priming in the visual modality. The present experiments examined the effect of divided attention on auditory implicit memory, using auditory perceptual identification, word-stem completion and word-fragment completion. Participants heard study words under full attention conditions or while simultaneously carrying out a distractor task (the divided attention condition). In Experiment 1, a distractor task with low response frequency failed to disrupt later auditory priming (but diminished explicit memory as assessed with auditory recognition). In Experiment 2, a distractor task with greater response frequency disrupted priming on all three of the auditory priming tasks as well as the explicit test. These results imply that although auditory priming is less reliant on attention than explicit memory, it is still greatly affected by at least some divided-attention manipulations. These results are consistent with research using visual priming tasks and have relevance for hypotheses regarding attention and auditory priming.