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Data from three experiments on serial perception of temporal intervals in the supra-second domain are reported. Sequences of short acoustic signals ("pips") separated by periods of silence were presented to the observers. Two types of time series, geometric or alternating, were used, where the modulus 1+δ of the inter-pip series and the base duration Tb (range from 1.1 to 6s) were varied as independent parameters. The observers had to judge whether the series were accelerating, decelerating, or uniform (3 paradigm), or to distinguish regular from irregular sequences (2 paradigm). "Intervals of subjective uniformity" (isus) were obtained by fitting Gaussian psychometric functions to individual subjects' responses. Progression towards longer base durations (Tb=4.4 or 6s) shifts the isus towards negative δs, i.e., accelerating series. This finding is compatible with the phenomenon of "subjective shortening" of past temporal intervals, which is naturally accounted for by the lossy integration model of internal time representation. The opposite effect observed for short durations (Tb=1.1 or 1.5s) remains unexplained by the lossy integration model, and presents a challenge for further research.
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A Concealed Information Test (CIT) investigates differential physiological responses to deed-related (probe) vs. irrelevant items. The present study focused on the detection of concealed information using simultaneous recordings of autonomic and brain electrical measures. As a secondary issue, verbal and pictorial presentations were compared with respect to their influence on the recorded measures. Thirty-one participants underwent a mock-crime scenario with a combined verbal and pictorial presentation of nine items. The subsequent CIT, designed with respect to event-related potential (ERP) measurement, used a 3-3.5s interstimulus interval. The item presentation modality, i.e. pictures or written words, was varied between subjects; no response was required from the participants. In addition to electroencephalogram (EEG), electrodermal activity (EDA), electrocardiogram (ECG), respiratory activity, and finger plethysmogram were recorded. A significant probe-vs.-irrelevant effect was found for each of the measures. Compared to sole ERP measurement, the combination of ERP and EDA yielded incremental information for detecting concealed information. Although, EDA per se did not reach the predictive value known from studies primarily designed for peripheral physiological measurement. Presentation modality neither influenced the detection accuracy for autonomic measures nor EEG measures; this underpins the equivalence of verbal and pictorial item presentation in a CIT, regardless of the physiological measures recorded. Future studies should further clarify whether the incremental validity observed in the present study reflects a differential sensitivity of ERP and EDA to different sub-processes in a CIT.
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Neuropsychological studies in brain-injured patients with aphasia and children with specific language-learning deficits have shown the dependence of language comprehension on auditory processing abilities, i.e. the detection of temporal order. An impairment of temporal-order perception can be simulated by time reversing segments of the speech signal. In our study, we investigated how different lengths of time-reversed segments in speech influenced comprehension in ten native German speakers and ten participants who had acquired German as a second language. Results show that native speakers were still able to understand the distorted speech at segment lengths of 50 ms, whereas non-native speakers only could identify sentences with reversed intervals of 32 ms duration. These differences in performance can be interpreted by different levels of semantic and lexical proficiency. Our method of temporally-distorted speech offers a new approach to assess language skills that indirectly taps into lexical and semantic competence of non-native speakers.
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Some authors have suggested separate mechanisms for the processing of temporal intervals above versus below 2-3s. Given that the evidence is mixed, the present experiment was carried out as a critical test of the separate-mechanism hypothesis. Subjects reproduced five standard durations of 1-5s presented in the auditory and visual modalities. The Corsi-block test was used to assess effects of working-memory span on different interval lengths. Greater working-memory span was associated with longer reproductions of intervals of 3-5s. A factor analysis run on mean reproduced intervals revealed one modality-unspecific factor for durations of 1-2s and two modality-specific factors for longer intervals. These results are interpreted as further indications that two different processes underlie temporal reproductions of shorter and longer intervals.
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PURPOSE: The relationship between auditory temporal-order perception and phoneme discrimination has been discussed for several years, based on findings, showing that patients with cerebral damage in the left hemisphere and aphasia, as well as children with specific language impairments, show deficits in temporal-processing and phoneme discrimination. Over the last years several temporal-order measurement procedures and training batteries have been developed. However, there exists no standard diagnostic tool for adults that could be applied to patients with aphasia. Therefore, our study aimed at identifying a feasible, reliable and efficient measurement procedure to test for auditory-temporal processing in healthy young and elderly adults, which in a further step can be applied to patients with aphasia. METHODS: The tasks varied according to adaptive procedures (staircase vs. maximum-likelihood), stimuli (tones vs. clicks) and stimulation modes (binaural- vs. alternating monaural) respectively. A phoneme-discrimination task was also employed to assess the relationship between temporal and language processing. RESULTS: The results show that auditory temporal-order thresholds are stimulus dependent, age related, and influenced by gender. Furthermore, the cited relationship between temporal-order threshold and phoneme discrimination can only be confirmed for measurements with pairs of tones. CONCLUSION: Our results indicate, that different norms have to be established for different gender and age groups. Furthermore, temporal-order measurements with tones seem to be more suitable for clinical intervention studies than measurements with clicks, as they show higher re-test reliabilities, and only for measurements with tones an association with phoneme-discrimination abilities was found.
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We assessed the effect of size and localization of a brain lesion on patients' abilities to perceive the temporal order of two acoustic stimuli. In those patients who had performed with impaired order thresholds, local overlaps of lesions as analyzed with CT were found in specific left-hemispheric regions of the temporal and parietal lobe. However, a moderate association of lesion size and temporal-order threshold was found among all brain-injured patients (n = 30), a correlation that was most pronounced in patients with right-hemispheric lesions. This non-specific effect of lesion size has to be discussed critically with respect to behavioral findings of an association between temporal-processing abilities and language competence.
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- Englisch (6)
Thema
- Acoustic Stimulation/methods
- Adult (5)
- Age Distribution (1)
- Aged (3)
- Aged, 80 and over (1)
- Aging/*physiology (1)
- Analysis of Variance (2)
- Auditory Perception/*physiology (3)
- Auditory Perception/physiology (1)
- Auditory Threshold/*physiology (1)
- Brain Injuries/pathology/*physiopathology (1)
- Brain Mapping (1)
- Cerebral Cortex/pathology/*physiopathology (1)
- Comprehension/*physiology (1)
- *Deception (1)
- Discrimination, Psychological (1)
- Discrimination, Psychological/*physiology (1)
- Duration discrimination (1)
- Electrocardiography/methods (1)
- Electroencephalography/methods (1)
- Evoked Potentials/*physiology (1)
- Factor Analysis, Statistical (1)
- Female (6)
- Fingers/blood supply (1)
- Functional Laterality/physiology (1)
- Galvanic Skin Response/physiology (1)
- Heart Rate/physiology (1)
- Humans (6)
- Interval of subjective uniformity (1)
- Judgment/physiology (1)
- Judgment/*physiology (1)
- *Language (1)
- Lie Detection/*psychology (1)
- Likelihood Functions (1)
- Logistic Models (1)
- Male (6)
- Memory, Short-Term/*physiology (1)
- Mental Processes/*physiology (1)
- Middle Aged (4)
- Perspectival contraction of time (1)
- Photic Stimulation/methods (2)
- Plethysmography/methods (1)
- Psychophysics/methods (1)
- Reaction Time/physiology (1)
- Reproducibility of Results (1)
- Respiration (1)
- *Sex Characteristics (1)
- Speech Discrimination Tests (1)
- Speech Perception/*physiology (1)
- Statistics, Nonparametric (2)
- Subjective shortening (1)
- Task Performance and Analysis (1)
- Time Factors (3)
- Time perception (1)
- Time Perception/*physiology (3)
- Tomography Scanners, X-Ray Computed (1)
- Uniformity illusion (1)
- Verbal Behavior/*physiology (1)
- Visual Perception/physiology (1)
- Young Adult (2)