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Auditory motion processing: Psychophysical and electrophysiological study
328
Abstracts / International Journal of Psychophysiology 77 (2010) 288–342
Conclusions: A significant increase in the MMN component after thirty-minute exposure suggests that 3G EMFs may have an impact on the automatic processing of unattended auditory stimuli. However, the possible behavioral consequences, if any, were not investigated in our current study. Therefore more experimental data are needed to draw a final conclusion about the effects of a relatively long 3G EMF exposure on automatic cortical auditory processing. This study was supported by Science, Please! Research Team on Innovation (SROP-4.2.2/08/1/2008-0011) to IH.
The investigation of lexical tone perception in Mandarin Chinese with different spectral resolution: An event-related potential (ERP) study Yu-ching Kuoa, Shih-kuen Chengb a Department of Special Education and Master Program of Speech Language Pathology, Taipei Municipal University of Education, Taipei, Taiwan b Institute of Cognitive Neuroscience, National Central University, Taipei, Taiwan
doi:10.1016/j.ijpsycho.2010.06.255
Temporal processing ability linked to ear-asymmetry in mismatch negativity (MMN) to between-channel gap sounds Juanita Todda,b, Brayden Fincha, Bill Budda,b, Ulrich Schallb,c a University of Newcastle, School of Psychology, Newcasle, Australia b University of Newcastle Priority Research Centre in Brain and Mental Health, Newcastle, Australia c University of Newcastle, School of Medicine and Population Health, Newcastle, Australia Background: A temporal processing advantage is thought to explain the left-hemisphere-dominance of language processing. This temporal processing advantage produces a right-ear-advantage on certain auditory tasks. We report the findings of two studies showing that individuals with better temporal processing ability exhibit larger functional asymmetry in brain measures of time processing. Method and results: Behavioural and brain measures of betweenchannel gap detection were used as an index of temporal processing ability. Our behavioural measure was the 79% correct threshold for detecting a gap in a between-channel sound. Our brain measure was the size of the mismatch-negativity (MMN) generated to a betweenchannel gap deviant sound in sequences of regular no-gap sounds. Equivalent sequences were presented separately monaurally to the left and right ear over headphones. The between-channel stimuli comprised broadband leading and trailing markers (either 2200– 2600 Hz or 3400–3800 Hz) with no frequency overlap between markers. In Study1, gap-detection threshold was positively correlated with ear-asymmetry in MMN measures in thirty-eight adults (18– 73 years). Larger right-ear-advantage in MMN correlated with better temporal discrimination ability (r = .51, p < .005). Although a significant decline in the right-ear advantage for MMN was observed with advancing age (r = .30, p < .05), the partial correlation between gap-threshold and right-ear advantage for MMN survived correction for age (r = .57, p < .005) supporting a strong ability-related asymmetry. In Study 2, analogous MMN sequences were presented to 19 young adults in silence and against a background of broadband noise (15 dB SNR). A significant interaction was present between noise, ear and group (p < .016). In good discriminators, the apparent right-earadvantage for MMN in silence was reversed to a left-ear-advantage for MMN in noise. Participants with higher thresholds (“poor” discriminators) showed no ear-advantage or differential sensitivity of the ears to noise. Conclusions: The results of both studies demonstrate an ability-related right-ear-advantage in MMN to betweenchannel gap deviant sounds. The right-ear-advantage is present only in “good discriminators”—those with low gap-detection thresholds in behavioural ability measures. We conclude that in good temporal discriminators, the MMN to between-channel gap sounds behaves like that to speech sounds by exhibiting a right-ear/left-hemisphere dominance in silence which is altered by the presence of noise.
doi:10.1016/j.ijpsycho.2010.06.256
Event-related potentials (ERPs) were recorded while normalhearing participants listened to cochlear implant simulations of different channel numbers, aiming to examine the relation between the number of channels in cochlear implants and the discrimination of lexical tones in Mandarin Chinese. Participants watched silent films while monosyllabic sounds of (Yi) in level and falling tones were played via loud speakers using different probabilities (level tone: 87.5%; falling tone: 12.5%). The mismatch negativity (MMN) component of auditory ERPs was used as an index of the discrimination between lexical tones under different channel numbers. The number of channels was manipulated across blocks. In one block, the speech sounds of Yi in level and falling tones recorded by a Mandarin Chinese speaker served as the stimuli. In the other blocks, the stimuli simulated the recorded sounds being transformed through 1-channel, 4-channel, and 8-channel cochlear implants, respectively. The MMN was observed in the speech sound condition: the waveforms elicited by the deviant stimuli were more negative than those elicited by the standard stimuli over frontal–central recording sites around 150–250 ms post stimulus onset. In the cochlear implant simulations, the MMN was observed in the 8channel conditions but not in 1-channel and 4-channel conditions. The MMN elicited in the 8-channel condition was of smaller magnitude than that in the speech sound condition. These findings suggest that 8 channels in cochlear implants may provide sufficient information for the auditory system to differentiate between lexical tones in Mandarin Chinese.
doi:10.1016/j.ijpsycho.2010.06.257
Auditory motion processing: Psychophysical and electrophysiological study L.B. Shestopalova, E.A. Petropavlovskaia, S.Ph. Vaitulevich, Y.A. Vasilenko Pavlov Institute of Physiology, Russian Academy of Sciences, St.-Petersburg, Russia One of the essentials of space perception is sound source localization. The analysis of sound stimulus spatial cues by the hearing system has been one of the targets of psychoacoustic and neurophysiologic research for years now. These two approaches formed the basis for the two main hypotheses concerning the moving sound source localization mechanism. Electrophysiological research brought about the hypothesis that there are specialized neural elements in the hearing system (“motion detectors”) that provide for the gradual analysis of sound source movement. On the other hand, the psychophysical data suggested the “snapshot” hypothesis, according to which the perception of horizontally moving sound does not invoke special motion mechanisms, but rather is based on the spatial discrimination of certain discrete points at its trajectory (the endpoints, for short time stimuli).
Abstracts / International Journal of Psychophysiology 77 (2010) 288–342
Purpose of study: The aim of our research was to find whether the processing of apparent auditory motion can be reduced to localization of the trajectory endpoints. Stimuli: The apparent auditory motion was simulated through manipulating interaural time differences (ITDs). The stimuli were the low pass noise bursts of 200 ms duration that either moved gradually to the left/right from the head midline or shifted abruptly by the same azimuth. The only acoustic difference between the stimuli was the ITD time pattern represented by either linear or step function. The trajectory lengths were defined by final ITD values which amounted to 200, 300, 400 … 800 μs. Behavioral study: A two-interval two-alternative forced-choice task was employed, the trajectory length being the main parameter. The subjects were asked to discriminate between gradual and abrupt displacement of the sound. EEG study: The EEG was recorded while the sound stimuli were presented in the odd-ball paradigm. The mismatch negativity (MMN) component of the auditory event-related potential was taken as an objective index of the auditory discrimination. MMN is elicited when repetitive sounds (standards) are interspersed by infrequent sounds (deviants) that differ along one or several dimensions from the previous sounds. The standard and deviant stimuli represented the gradual and abrupt sound motion, respectively. The trajectory length corresponded to ITD values of 200 and 800 μs (short and long trajectories, respectively). Results: Psychophysical discrimination of abrupt and gradual sound movement depended on the trajectory length but generally did not reach the threshold level (75%) providing the supporting evidence that gradual and abrupt auditory motion could not be distinguished by the hearing system, as it would be expected from the “snapshot” theory. The MMN study showed, however, that significant MMN was elicited by all deviant stimuli. The deviants that travelled over short and long trajectories caused MMNs which differed in magnitude. These findings imply that the MMN-generating system successfully discriminated between gradual and abrupt sound motion, which suggests the greater sensitivity of the electrophysiological measure to the spatial properties of the moving sound. Conclusion: The present study established the objective evidence that motion discrimination is based not only on trajectory endpoints, but on the midportions of sound stimuli as well, which could hardly be consistent with the “snapshot” hypothesis. Besides, the discrepancy between the psychophysical performance and the MMN data indicate that behavioral discrimination should not be brought into direct correlation with any specific electrophysiological phenomena. This study was supported by the grants NS-3866.2008.4 and RFBR 08-04-00006. doi:10.1016/j.ijpsycho.2010.06.258
Effects of learned helplessness on performance and event-related potentials in a learning task Uta Sailera, Florian Ph.S. Fischmeistera,b,c, Herbert Bauera a Faculty of Psychology, University of Vienna, Vienna, Austria b MR Centre of Excellence, Medical University of Vienna, Vienna, Austria c Centre for Biomedical Engineering and Physics, Medical University of Vienna, Vienna, Austria This study investigated how learned helplessness affects performance and feedback-related brain potentials in a task that required participants to learn a pattern of correct responses. To this aim, learning performance as well as the amplitudes of the feedbackrelated negativity (FRN) and the P3 to gain and loss feedback were compared between the early and late phases of the experiment.
329
Generally, the P3 was more sensitive to both effects of learning and of learned helplessness. The P3 was smaller in the late phase compared with the early phase, and in learners compared to non-learners. This decrease may be due to reduced task-related effort or subjective outcome probability that is associated with learning. The FRN was smaller for learners than non-learners, possibly because of an increased predictability of both gain and loss outcomes for learners. Subjects with learned helplessness showed lower behavioural efficiency despite a similar percentage of correct responses. The slight performance impairment was accompanied by a larger P3 in helpless subjects as compared to controls. This suggests that helpless subjects relied on ineffective task strategies despite being motivated and attentive. Our findings confirm previous results on learning-related changes in event-related potentials and provide novel insights into the nature of performance impairments in learned helplessness. doi:10.1016/j.ijpsycho.2010.06.259
Influence of auditory rhythmic stimulation and genomic factors on cognitive task solution G.V. Portnova, O.V. Sysoeva Institute for Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia The process of time perception can be related to different factors. Previous data show that there are different internal (physiological, genomic) and external (rhythmic stimulation) factors that are influenced during different cognitive solving tasks. Forty two subjects took part in the experiment. The experiment consisted of two different subject groups. In the first experiment the task was “difficult”: definition of the word category as concrete, abstract or pseudo-word and evaluation of time intervals (long, middle or short duration). The second experiment involved reaction time. Subjects were asked to accomplish simple tasks: simple motor reaction or a choosing reaction. A ticking clock was presented as audio rhythmic stimulation with 0.75, 1 or 1.25 Hz. Rhythmic background presentation was shared to 11 series. EEG was recorded during the experiment. ERPs, rhythm spectrum, and behavior answers were analyzed and compared with T-criteria of students. All subjects were genotyped for COMT, 5-HTT, 5HT2a, MAOA, and DAT genes. Results showed that rhythmic background influenced time evaluation and response time. Subjects solved tasks quicker and estimated series as shorter during slow clock ticks in comparison with the faster clock tick. During time evaluation and word categorization tasks P300 component of ERP in central, right frontal and temporal areas were more positive during slow clock ticks (0.75 Hz) than during fast (1.25 Hz) ticks. Power of alpha-rhythm spectrum was higher in series without background rhythm and was minimal during background rhythm (0.75 Hz). During simple motor reaction fast background rhythm makes reaction time decreased in comparison with slow background rhythm and rhythm absence. Subjects with MM polymorphisms of COMT gene didn't show differences between different frequencies of background rhythm in reaction time or any brain answers. Thus, results showed that association of time perception with different genes and mediators suggested different mechanisms, working in different time ranges, in concordance with the previous physiological studies. Alpha-rhythm power and P300 amplitude are related with attention processes and gene COMT polymorphisms appeared to be related with these brain activity components. In our work Alpha-rhythm power, P300 and gene COMT polymorphisms were also correlated with reaction time and evaluation of time intervals. doi:10.1016/j.ijpsycho.2010.06.260
Abstracts / International Journal of Psychophysiology 77 (2010) 288–342
Conclusions: A significant increase in the MMN component after thirty-minute exposure suggests that 3G EMFs may have an impact on the automatic processing of unattended auditory stimuli. However, the possible behavioral consequences, if any, were not investigated in our current study. Therefore more experimental data are needed to draw a final conclusion about the effects of a relatively long 3G EMF exposure on automatic cortical auditory processing. This study was supported by Science, Please! Research Team on Innovation (SROP-4.2.2/08/1/2008-0011) to IH.
The investigation of lexical tone perception in Mandarin Chinese with different spectral resolution: An event-related potential (ERP) study Yu-ching Kuoa, Shih-kuen Chengb a Department of Special Education and Master Program of Speech Language Pathology, Taipei Municipal University of Education, Taipei, Taiwan b Institute of Cognitive Neuroscience, National Central University, Taipei, Taiwan
doi:10.1016/j.ijpsycho.2010.06.255
Temporal processing ability linked to ear-asymmetry in mismatch negativity (MMN) to between-channel gap sounds Juanita Todda,b, Brayden Fincha, Bill Budda,b, Ulrich Schallb,c a University of Newcastle, School of Psychology, Newcasle, Australia b University of Newcastle Priority Research Centre in Brain and Mental Health, Newcastle, Australia c University of Newcastle, School of Medicine and Population Health, Newcastle, Australia Background: A temporal processing advantage is thought to explain the left-hemisphere-dominance of language processing. This temporal processing advantage produces a right-ear-advantage on certain auditory tasks. We report the findings of two studies showing that individuals with better temporal processing ability exhibit larger functional asymmetry in brain measures of time processing. Method and results: Behavioural and brain measures of betweenchannel gap detection were used as an index of temporal processing ability. Our behavioural measure was the 79% correct threshold for detecting a gap in a between-channel sound. Our brain measure was the size of the mismatch-negativity (MMN) generated to a betweenchannel gap deviant sound in sequences of regular no-gap sounds. Equivalent sequences were presented separately monaurally to the left and right ear over headphones. The between-channel stimuli comprised broadband leading and trailing markers (either 2200– 2600 Hz or 3400–3800 Hz) with no frequency overlap between markers. In Study1, gap-detection threshold was positively correlated with ear-asymmetry in MMN measures in thirty-eight adults (18– 73 years). Larger right-ear-advantage in MMN correlated with better temporal discrimination ability (r = .51, p < .005). Although a significant decline in the right-ear advantage for MMN was observed with advancing age (r = .30, p < .05), the partial correlation between gap-threshold and right-ear advantage for MMN survived correction for age (r = .57, p < .005) supporting a strong ability-related asymmetry. In Study 2, analogous MMN sequences were presented to 19 young adults in silence and against a background of broadband noise (15 dB SNR). A significant interaction was present between noise, ear and group (p < .016). In good discriminators, the apparent right-earadvantage for MMN in silence was reversed to a left-ear-advantage for MMN in noise. Participants with higher thresholds (“poor” discriminators) showed no ear-advantage or differential sensitivity of the ears to noise. Conclusions: The results of both studies demonstrate an ability-related right-ear-advantage in MMN to betweenchannel gap deviant sounds. The right-ear-advantage is present only in “good discriminators”—those with low gap-detection thresholds in behavioural ability measures. We conclude that in good temporal discriminators, the MMN to between-channel gap sounds behaves like that to speech sounds by exhibiting a right-ear/left-hemisphere dominance in silence which is altered by the presence of noise.
doi:10.1016/j.ijpsycho.2010.06.256
Event-related potentials (ERPs) were recorded while normalhearing participants listened to cochlear implant simulations of different channel numbers, aiming to examine the relation between the number of channels in cochlear implants and the discrimination of lexical tones in Mandarin Chinese. Participants watched silent films while monosyllabic sounds of (Yi) in level and falling tones were played via loud speakers using different probabilities (level tone: 87.5%; falling tone: 12.5%). The mismatch negativity (MMN) component of auditory ERPs was used as an index of the discrimination between lexical tones under different channel numbers. The number of channels was manipulated across blocks. In one block, the speech sounds of Yi in level and falling tones recorded by a Mandarin Chinese speaker served as the stimuli. In the other blocks, the stimuli simulated the recorded sounds being transformed through 1-channel, 4-channel, and 8-channel cochlear implants, respectively. The MMN was observed in the speech sound condition: the waveforms elicited by the deviant stimuli were more negative than those elicited by the standard stimuli over frontal–central recording sites around 150–250 ms post stimulus onset. In the cochlear implant simulations, the MMN was observed in the 8channel conditions but not in 1-channel and 4-channel conditions. The MMN elicited in the 8-channel condition was of smaller magnitude than that in the speech sound condition. These findings suggest that 8 channels in cochlear implants may provide sufficient information for the auditory system to differentiate between lexical tones in Mandarin Chinese.
doi:10.1016/j.ijpsycho.2010.06.257
Auditory motion processing: Psychophysical and electrophysiological study L.B. Shestopalova, E.A. Petropavlovskaia, S.Ph. Vaitulevich, Y.A. Vasilenko Pavlov Institute of Physiology, Russian Academy of Sciences, St.-Petersburg, Russia One of the essentials of space perception is sound source localization. The analysis of sound stimulus spatial cues by the hearing system has been one of the targets of psychoacoustic and neurophysiologic research for years now. These two approaches formed the basis for the two main hypotheses concerning the moving sound source localization mechanism. Electrophysiological research brought about the hypothesis that there are specialized neural elements in the hearing system (“motion detectors”) that provide for the gradual analysis of sound source movement. On the other hand, the psychophysical data suggested the “snapshot” hypothesis, according to which the perception of horizontally moving sound does not invoke special motion mechanisms, but rather is based on the spatial discrimination of certain discrete points at its trajectory (the endpoints, for short time stimuli).
Abstracts / International Journal of Psychophysiology 77 (2010) 288–342
Purpose of study: The aim of our research was to find whether the processing of apparent auditory motion can be reduced to localization of the trajectory endpoints. Stimuli: The apparent auditory motion was simulated through manipulating interaural time differences (ITDs). The stimuli were the low pass noise bursts of 200 ms duration that either moved gradually to the left/right from the head midline or shifted abruptly by the same azimuth. The only acoustic difference between the stimuli was the ITD time pattern represented by either linear or step function. The trajectory lengths were defined by final ITD values which amounted to 200, 300, 400 … 800 μs. Behavioral study: A two-interval two-alternative forced-choice task was employed, the trajectory length being the main parameter. The subjects were asked to discriminate between gradual and abrupt displacement of the sound. EEG study: The EEG was recorded while the sound stimuli were presented in the odd-ball paradigm. The mismatch negativity (MMN) component of the auditory event-related potential was taken as an objective index of the auditory discrimination. MMN is elicited when repetitive sounds (standards) are interspersed by infrequent sounds (deviants) that differ along one or several dimensions from the previous sounds. The standard and deviant stimuli represented the gradual and abrupt sound motion, respectively. The trajectory length corresponded to ITD values of 200 and 800 μs (short and long trajectories, respectively). Results: Psychophysical discrimination of abrupt and gradual sound movement depended on the trajectory length but generally did not reach the threshold level (75%) providing the supporting evidence that gradual and abrupt auditory motion could not be distinguished by the hearing system, as it would be expected from the “snapshot” theory. The MMN study showed, however, that significant MMN was elicited by all deviant stimuli. The deviants that travelled over short and long trajectories caused MMNs which differed in magnitude. These findings imply that the MMN-generating system successfully discriminated between gradual and abrupt sound motion, which suggests the greater sensitivity of the electrophysiological measure to the spatial properties of the moving sound. Conclusion: The present study established the objective evidence that motion discrimination is based not only on trajectory endpoints, but on the midportions of sound stimuli as well, which could hardly be consistent with the “snapshot” hypothesis. Besides, the discrepancy between the psychophysical performance and the MMN data indicate that behavioral discrimination should not be brought into direct correlation with any specific electrophysiological phenomena. This study was supported by the grants NS-3866.2008.4 and RFBR 08-04-00006. doi:10.1016/j.ijpsycho.2010.06.258
Effects of learned helplessness on performance and event-related potentials in a learning task Uta Sailera, Florian Ph.S. Fischmeistera,b,c, Herbert Bauera a Faculty of Psychology, University of Vienna, Vienna, Austria b MR Centre of Excellence, Medical University of Vienna, Vienna, Austria c Centre for Biomedical Engineering and Physics, Medical University of Vienna, Vienna, Austria This study investigated how learned helplessness affects performance and feedback-related brain potentials in a task that required participants to learn a pattern of correct responses. To this aim, learning performance as well as the amplitudes of the feedbackrelated negativity (FRN) and the P3 to gain and loss feedback were compared between the early and late phases of the experiment.
329
Generally, the P3 was more sensitive to both effects of learning and of learned helplessness. The P3 was smaller in the late phase compared with the early phase, and in learners compared to non-learners. This decrease may be due to reduced task-related effort or subjective outcome probability that is associated with learning. The FRN was smaller for learners than non-learners, possibly because of an increased predictability of both gain and loss outcomes for learners. Subjects with learned helplessness showed lower behavioural efficiency despite a similar percentage of correct responses. The slight performance impairment was accompanied by a larger P3 in helpless subjects as compared to controls. This suggests that helpless subjects relied on ineffective task strategies despite being motivated and attentive. Our findings confirm previous results on learning-related changes in event-related potentials and provide novel insights into the nature of performance impairments in learned helplessness. doi:10.1016/j.ijpsycho.2010.06.259
Influence of auditory rhythmic stimulation and genomic factors on cognitive task solution G.V. Portnova, O.V. Sysoeva Institute for Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia The process of time perception can be related to different factors. Previous data show that there are different internal (physiological, genomic) and external (rhythmic stimulation) factors that are influenced during different cognitive solving tasks. Forty two subjects took part in the experiment. The experiment consisted of two different subject groups. In the first experiment the task was “difficult”: definition of the word category as concrete, abstract or pseudo-word and evaluation of time intervals (long, middle or short duration). The second experiment involved reaction time. Subjects were asked to accomplish simple tasks: simple motor reaction or a choosing reaction. A ticking clock was presented as audio rhythmic stimulation with 0.75, 1 or 1.25 Hz. Rhythmic background presentation was shared to 11 series. EEG was recorded during the experiment. ERPs, rhythm spectrum, and behavior answers were analyzed and compared with T-criteria of students. All subjects were genotyped for COMT, 5-HTT, 5HT2a, MAOA, and DAT genes. Results showed that rhythmic background influenced time evaluation and response time. Subjects solved tasks quicker and estimated series as shorter during slow clock ticks in comparison with the faster clock tick. During time evaluation and word categorization tasks P300 component of ERP in central, right frontal and temporal areas were more positive during slow clock ticks (0.75 Hz) than during fast (1.25 Hz) ticks. Power of alpha-rhythm spectrum was higher in series without background rhythm and was minimal during background rhythm (0.75 Hz). During simple motor reaction fast background rhythm makes reaction time decreased in comparison with slow background rhythm and rhythm absence. Subjects with MM polymorphisms of COMT gene didn't show differences between different frequencies of background rhythm in reaction time or any brain answers. Thus, results showed that association of time perception with different genes and mediators suggested different mechanisms, working in different time ranges, in concordance with the previous physiological studies. Alpha-rhythm power and P300 amplitude are related with attention processes and gene COMT polymorphisms appeared to be related with these brain activity components. In our work Alpha-rhythm power, P300 and gene COMT polymorphisms were also correlated with reaction time and evaluation of time intervals. doi:10.1016/j.ijpsycho.2010.06.260