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John Polich - One of the best experts on this subject based on the ideXlab platform.
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p3a from white noise
International Journal of Psychophysiology, 2012Co-Authors: David W Frank, John PolichAbstract:P3a and P3b event-related brain potentials (ERPs) were elicited with an auditory three-stimulus (target, distracter, and standard) discrimination task in which subjects responded only to the target. Distracter stimuli consisted of white noise or novel sounds with stimulus characteristics perceptually matched. Target/standard discrimination difficulty was manipulated by varying target/standard pitch differences to produce relatively easy, medium, and hard tasks. Error rate and response time increased with increases in task difficulty. P3a was larger for the white noise compared to novel sounds, maximum over the central/parietal recording sites, and did not differ in size across difficulty levels. P3b was unaffected by distracter type, decreased as task difficulty increased, and maximum over the parietal recording sites. The findings indicate that P3a from white noise is robust and should be useful for applied studies as it removes stimulus novelty variability. Theoretical perspectives are discussed.
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age physical fitness and attention p3a and P3b
Psychophysiology, 2009Co-Authors: Matthew B Pontifex, Charles H Hillman, John PolichAbstract:The influence of age and fitness on the neuroelectric correlates of attentional orienting and processing during stimulus discrimination were investigated. Younger and older adult participants completed a maximal aerobic exercise test and were separated into higher- and lower-fit groups according to their cardiorespiratory fitness. Task performance and event-related potential measures were obtained during two- and three-stimulus oddball tasks. Results indicated that fitness may ameliorate or protect against cognitive aging for simple stimulus discriminations. Increases in task difficulty indicated that fitness may not be sufficient to overcome age-related deficits in stimulus discrimination. Further, fitness did not influence attentional orienting. The findings suggest that fitness-related changes in cognitive function may originate from other attentional mechanisms. Theoretical implications are discussed.
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updating p300 an integrative theory of p3a and P3b
Clinical Neurophysiology, 2007Co-Authors: John PolichAbstract:The empirical and theoretical development of the P300 event-related brain potential (ERP) is reviewed by considering factors that contribute to its amplitude, latency, and general characteristics. The neuropsychological origins of the P3a and P3b subcomponents are detailed, and how target/standard discrimination difficulty modulates scalp topography is discussed. The neural loci of P3a and P3b generation are outlined, and a cognitive model is proffered: P3a originates from stimulus-driven frontal attention mechanisms during task processing, whereas P3b originates from temporal-parietal activity associated with attention and appears related to subsequent memory processing. Neurotransmitter actions associating P3a to frontal/dopaminergic and P3b to parietal/norepinephrine pathways are highlighted. Neuroinhibition is suggested as an overarching theoretical mechanism for P300, which is elicited when stimulus detection engages memory operations.
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normative variation of p3a and P3b from a large sample
Journal of Psychophysiology, 2007Co-Authors: Matthew A Conroy, John PolichAbstract:Abstract. The P3a and P3b components were elicited in 120 (60 females, 60 males) young adults using a visual three-stimulus event-related brain potential (ERP) oddball paradigm in which subjects responded to an infrequent target. The major purpose of the paper was to provide a statistically strong characterization of these related P300 subcomponents. P3a components were obtained from the infrequently presented distracter stimulus, which was a large blue square. P3b components were obtained from the target stimulus, which was a blue circle that differed slightly in diameter from the standard stimulus blue circle. Amplitude measures demonstrated that P3a was maximum at Cz, and P3b was maximum at Pz; latency measures increased for both potentials from frontal to parietal recording sites. P3a and P3b from females were larger and later than those from male subjects, with topographic and appreciable individual difference variability observed. P3a was generally unrelated to response time. P3b amplitude was negat...
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neuropsychology and neuropharmacology of p3a and P3b
International Journal of Psychophysiology, 2006Co-Authors: John Polich, Josep Rialp CriadoAbstract:Perspectives on the P300 event-related brain potential (ERP) are reviewed by outlining the distinction between the P3a and P3b subcomponents. The critical factor for eliciting P3a is how target/standard discrimination difficulty rather than novelty modulates task processing. The neural loci of P3a and P3b generation are sketched and a theoretical model is developed. P3a originates from stimulus-driven disruption of frontal attention engagement during task processing. P3b originates when temporal-parietal mechanisms process the stimulus information for memory storage. The neuropharmacological implications of this view are then outlined by evaluating how acute and chronic use of ethanol, marijuana, and nicotine affect P3a and P3b. The findings suggest that the circuit underlying ERP generation is influenced in a different ways for acute intake and varies between chronic use levels across drugs. Theoretical implications are assessed.
Kristine B Walhovd - One of the best experts on this subject based on the ideXlab platform.
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Cognitive function, P3a/P3b brain potentials, and cortical thickness in aging
Human Brain Mapping, 2020Co-Authors: Anders M Fjell, Kristine B Walhovd, Bruce Fischl, Ivar ReinvangAbstract:The purpose of the study was to assess the relationship between the P3a/P3b brain poten- tials, cortical thickness, and cognitive function in aging. Thirty-five younger and 37 older healthy par- ticipants completed a visual three-stimuli oddball ERP (event-related potential)-paradigm, a battery of neuropsychological tests, and MRI scans. Groups with short vs. long latency, and low vs. high ampli- tude, were compared on a point by point basis across the entire cortical mantle. In the young, thickness was only weakly related to P3. In the elderly, P3a amplitude effects were found in parietal areas, the temporoparietal junction, and parts of the posterior cingulate cortex. P3b latency was especially related to cortical thickness in large frontal regions. Path models with the whole sample pooled together were constructed, demonstrating that cortical thickness in the temporoparietal cortex predicted P3a ampli- tude, which in turn predicted executive function, and that thickness in orbitofrontal cortex predicted P3b latency, which in turn predicted fluid function. When age was included in the model, the relation- ship between P3 and cognitive function vanished, while the relationship between regional cortical thickness and P3 remained. It is concluded that thickness in specific cortical areas correlates with scalp recorded P3a/P3b in elderly, and that these relationships differentially mediate higher cognitive func- tion. Hum Brain Mapp 28:1098-1116, 2007. V V C 2007 Wiley-Liss, Inc.
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instability in the latency of p3a P3b brain potentials and cognitive function in aging
Neurobiology of Aging, 2009Co-Authors: Anders M Fjell, Hannah Rosquist, Kristine B WalhovdAbstract:Instability in performance is a prominent feature of aging. In this study, 133 participants evenly distributed across the adult lifespan underwent a three-stimulus event-related potentials (ERPs) paradigm, and instability in P3a/P3b latency and reaction time (RT) were measured. P3a is related to alertness or reorientation of attention and it was elicited by distractor stimuli. P3b is related to controlled attentional processes and it was triggered by target stimuli. Maximum-likelihood estimation (MLE) was used to quantify the level of variability in latency across the single sweep ERPs. The results revealed increased variability in RT but not in P3a/P3b latency with age. Variability in P3a/P3b latency was related to executive functions, and variability in RT to speed. Generally, the relationships tended to increase with age. It can be concluded that increased variability in RT with age is caused by instability in processes related to response execution and possibly response selection, but not stimulus classification. Further, the results indicate that intraindividual variability is not a uniform concept, but has unique explanatory value at the neurophysiological and behavioral level.
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Instability in the latency of P3a/P3b brain potentials and cognitive function in aging
Neurobiology of Aging, 2008Co-Authors: Anders M Fjell, Hannah Rosquist, Kristine B WalhovdAbstract:Instability in performance is a prominent feature of aging. In this study, 133 participants evenly distributed across the adult lifespan underwent a three-stimulus event-related potentials (ERPs) paradigm, and instability in P3a/P3b latency and reaction time (RT) were measured. P3a is related to alertness or reorientation of attention and it was elicited by distractor stimuli. P3b is related to controlled attentional processes and it was triggered by target stimuli. Maximum-likelihood estimation (MLE) was used to quantify the level of variability in latency across the single sweep ERPs. The results revealed increased variability in RT but not in P3a/P3b latency with age. Variability in P3a/P3b latency was related to executive functions, and variability in RT to speed. Generally, the relationships tended to increase with age. It can be concluded that increased variability in RT with age is caused by instability in processes related to response execution and possibly response selection, but not stimulus classification. Further, the results indicate that intraindividual variability is not a uniform concept, but has unique explanatory value at the neurophysiological and behavioral level.
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the development of visual p3a and P3b
Developmental Neuropsychology, 2007Co-Authors: Signe Hjelen Stige, Anders M Fjell, Magnus Lindgren, Lars Smith, Kristine B WalhovdAbstract:The relationship of visual P3a and P3b to age and neuropsychological performance was investigated in 26 healthy children (6.8-15.8 years) and 129 adult volunteers (20.0-88.8 years). Within the sample of children, an effect of age on midline topography was observed, with higher frontal amplitudes in the youngest compared to the oldest children. Increasing age was associated with lower P3a and P3b amplitude and shorter P3b latency at Fz. Performance on neuropsychological tests (matrix reasoning from WASI, digit span from WAIS, word order and hand movement from Kaufman) was only weakly associated with measures of P3a and P3b. The analyses were then repeated with the full life-span sample (n = 155). It was found that for P3a, amplitude decreased and latency increased with age. For P3b, the pattern was more complex, with a nonlinear amplitude reduction and no latency change with age. It appears that the development of P3a in children represents the start of processes that later continue in the adult life-span, but that the automatic processes indexed by P3a seems to mature earlier than the controlled processes reflected by P3b. Finally, it was demonstrated that the relationships between neuropsychological test scores (matrix reasoning, digit span) and P3 parameters were complex, following a mix of linear and nonlinear patterns. It is suggested that the neuropsychological significance of the different P3a and P3b parameters may change from childhood to the adult life-span.
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cognitive function p3a P3b brain potentials and cortical thickness in aging
Human Brain Mapping, 2007Co-Authors: Anders M Fjell, Kristine B Walhovd, Bruce Fischl, Ivar ReinvangAbstract:The purpose of the study was to assess the relationship between the P3a/P3b brain poten- tials, cortical thickness, and cognitive function in aging. Thirty-five younger and 37 older healthy par- ticipants completed a visual three-stimuli oddball ERP (event-related potential)-paradigm, a battery of neuropsychological tests, and MRI scans. Groups with short vs. long latency, and low vs. high ampli- tude, were compared on a point by point basis across the entire cortical mantle. In the young, thickness was only weakly related to P3. In the elderly, P3a amplitude effects were found in parietal areas, the temporoparietal junction, and parts of the posterior cingulate cortex. P3b latency was especially related to cortical thickness in large frontal regions. Path models with the whole sample pooled together were constructed, demonstrating that cortical thickness in the temporoparietal cortex predicted P3a ampli- tude, which in turn predicted executive function, and that thickness in orbitofrontal cortex predicted P3b latency, which in turn predicted fluid function. When age was included in the model, the relation- ship between P3 and cognitive function vanished, while the relationship between regional cortical thickness and P3 remained. It is concluded that thickness in specific cortical areas correlates with scalp recorded P3a/P3b in elderly, and that these relationships differentially mediate higher cognitive func- tion. Hum Brain Mapp 28:1098-1116, 2007. V V C 2007 Wiley-Liss, Inc.
Anders M Fjell - One of the best experts on this subject based on the ideXlab platform.
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Cognitive function, P3a/P3b brain potentials, and cortical thickness in aging
Human Brain Mapping, 2020Co-Authors: Anders M Fjell, Kristine B Walhovd, Bruce Fischl, Ivar ReinvangAbstract:The purpose of the study was to assess the relationship between the P3a/P3b brain poten- tials, cortical thickness, and cognitive function in aging. Thirty-five younger and 37 older healthy par- ticipants completed a visual three-stimuli oddball ERP (event-related potential)-paradigm, a battery of neuropsychological tests, and MRI scans. Groups with short vs. long latency, and low vs. high ampli- tude, were compared on a point by point basis across the entire cortical mantle. In the young, thickness was only weakly related to P3. In the elderly, P3a amplitude effects were found in parietal areas, the temporoparietal junction, and parts of the posterior cingulate cortex. P3b latency was especially related to cortical thickness in large frontal regions. Path models with the whole sample pooled together were constructed, demonstrating that cortical thickness in the temporoparietal cortex predicted P3a ampli- tude, which in turn predicted executive function, and that thickness in orbitofrontal cortex predicted P3b latency, which in turn predicted fluid function. When age was included in the model, the relation- ship between P3 and cognitive function vanished, while the relationship between regional cortical thickness and P3 remained. It is concluded that thickness in specific cortical areas correlates with scalp recorded P3a/P3b in elderly, and that these relationships differentially mediate higher cognitive func- tion. Hum Brain Mapp 28:1098-1116, 2007. V V C 2007 Wiley-Liss, Inc.
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instability in the latency of p3a P3b brain potentials and cognitive function in aging
Neurobiology of Aging, 2009Co-Authors: Anders M Fjell, Hannah Rosquist, Kristine B WalhovdAbstract:Instability in performance is a prominent feature of aging. In this study, 133 participants evenly distributed across the adult lifespan underwent a three-stimulus event-related potentials (ERPs) paradigm, and instability in P3a/P3b latency and reaction time (RT) were measured. P3a is related to alertness or reorientation of attention and it was elicited by distractor stimuli. P3b is related to controlled attentional processes and it was triggered by target stimuli. Maximum-likelihood estimation (MLE) was used to quantify the level of variability in latency across the single sweep ERPs. The results revealed increased variability in RT but not in P3a/P3b latency with age. Variability in P3a/P3b latency was related to executive functions, and variability in RT to speed. Generally, the relationships tended to increase with age. It can be concluded that increased variability in RT with age is caused by instability in processes related to response execution and possibly response selection, but not stimulus classification. Further, the results indicate that intraindividual variability is not a uniform concept, but has unique explanatory value at the neurophysiological and behavioral level.
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Instability in the latency of P3a/P3b brain potentials and cognitive function in aging
Neurobiology of Aging, 2008Co-Authors: Anders M Fjell, Hannah Rosquist, Kristine B WalhovdAbstract:Instability in performance is a prominent feature of aging. In this study, 133 participants evenly distributed across the adult lifespan underwent a three-stimulus event-related potentials (ERPs) paradigm, and instability in P3a/P3b latency and reaction time (RT) were measured. P3a is related to alertness or reorientation of attention and it was elicited by distractor stimuli. P3b is related to controlled attentional processes and it was triggered by target stimuli. Maximum-likelihood estimation (MLE) was used to quantify the level of variability in latency across the single sweep ERPs. The results revealed increased variability in RT but not in P3a/P3b latency with age. Variability in P3a/P3b latency was related to executive functions, and variability in RT to speed. Generally, the relationships tended to increase with age. It can be concluded that increased variability in RT with age is caused by instability in processes related to response execution and possibly response selection, but not stimulus classification. Further, the results indicate that intraindividual variability is not a uniform concept, but has unique explanatory value at the neurophysiological and behavioral level.
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the development of visual p3a and P3b
Developmental Neuropsychology, 2007Co-Authors: Signe Hjelen Stige, Anders M Fjell, Magnus Lindgren, Lars Smith, Kristine B WalhovdAbstract:The relationship of visual P3a and P3b to age and neuropsychological performance was investigated in 26 healthy children (6.8-15.8 years) and 129 adult volunteers (20.0-88.8 years). Within the sample of children, an effect of age on midline topography was observed, with higher frontal amplitudes in the youngest compared to the oldest children. Increasing age was associated with lower P3a and P3b amplitude and shorter P3b latency at Fz. Performance on neuropsychological tests (matrix reasoning from WASI, digit span from WAIS, word order and hand movement from Kaufman) was only weakly associated with measures of P3a and P3b. The analyses were then repeated with the full life-span sample (n = 155). It was found that for P3a, amplitude decreased and latency increased with age. For P3b, the pattern was more complex, with a nonlinear amplitude reduction and no latency change with age. It appears that the development of P3a in children represents the start of processes that later continue in the adult life-span, but that the automatic processes indexed by P3a seems to mature earlier than the controlled processes reflected by P3b. Finally, it was demonstrated that the relationships between neuropsychological test scores (matrix reasoning, digit span) and P3 parameters were complex, following a mix of linear and nonlinear patterns. It is suggested that the neuropsychological significance of the different P3a and P3b parameters may change from childhood to the adult life-span.
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cognitive function p3a P3b brain potentials and cortical thickness in aging
Human Brain Mapping, 2007Co-Authors: Anders M Fjell, Kristine B Walhovd, Bruce Fischl, Ivar ReinvangAbstract:The purpose of the study was to assess the relationship between the P3a/P3b brain poten- tials, cortical thickness, and cognitive function in aging. Thirty-five younger and 37 older healthy par- ticipants completed a visual three-stimuli oddball ERP (event-related potential)-paradigm, a battery of neuropsychological tests, and MRI scans. Groups with short vs. long latency, and low vs. high ampli- tude, were compared on a point by point basis across the entire cortical mantle. In the young, thickness was only weakly related to P3. In the elderly, P3a amplitude effects were found in parietal areas, the temporoparietal junction, and parts of the posterior cingulate cortex. P3b latency was especially related to cortical thickness in large frontal regions. Path models with the whole sample pooled together were constructed, demonstrating that cortical thickness in the temporoparietal cortex predicted P3a ampli- tude, which in turn predicted executive function, and that thickness in orbitofrontal cortex predicted P3b latency, which in turn predicted fluid function. When age was included in the model, the relation- ship between P3 and cognitive function vanished, while the relationship between regional cortical thickness and P3 remained. It is concluded that thickness in specific cortical areas correlates with scalp recorded P3a/P3b in elderly, and that these relationships differentially mediate higher cognitive func- tion. Hum Brain Mapp 28:1098-1116, 2007. V V C 2007 Wiley-Liss, Inc.
Marco Comerchero - One of the best experts on this subject based on the ideXlab platform.
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P3a from Visual Stimuli: Typicality, Task, and Topography
Brain Topography, 2003Co-Authors: John Polich, Marco ComercheroAbstract:A visual three-stimulus (target, nontarget, standard) paradigm was employed in which subjects responded only to the target. Nontarget stimulus properties were varied systematically to evaluate how stimulus typicality (non-novel vs. novel) across task discrimination (easy vs. difficult) conditions affects P3a scalp topography. Nontarget stimuli consisted of letters, small squares, large squares, and novel patterns; discrimination difficulty between the target and standard was varied across conditions. When the discrimination was easy, P300 amplitude was larger for the target than the nontarget with parietal maximums for both. In contrast, when the discrimination was difficult, nontarget amplitude (P3a) was larger and earlier than the target P300 over the frontal/central electrode sites, whereas target amplitude (P3b) was larger parietally and occurred later. P3a was largest when elicited by either the large square or novel pattern stimuli. The findings suggest that stimulus context as defined by the target/standard discrimination difficulty rather than stimulus novelty determines P3a generation.
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Wavelet Analysis of P3a and P3b
Brain Topography, 2001Co-Authors: Tamer Demiralp, Ahmet Ademoglu, Marco Comerchero, John PolichAbstract:Target/standard discrimination difficulty and the degree of stimulus "novelty" were manipulated systematically in a three-stimulus oddball task to assess how these variables affect target and non-target P300 scalp distributions for visual stimuli. Wavelet transformation (WT) analyses were performed on the non-target (P3a) and target (P3b) ERPs to assay how the underlying electroencephalographic (EEG) activity was affected by both the difficulty and novelty factors. When target/standard discrimination was easy, P300 amplitude was higher for the target than the non-target across all electrode sites, and both demonstrated parietal maximums. In contrast, when target/standard discrimination was difficult, non-target amplitude (P3a) was higher and earlier over the frontal/central electrode sites for both levels of novelty, whereas target amplitude (P3b) was greater parietally and occurred later than the non-target components and was generally unaffected by non-target novelty level. The WT analyses indicated that appreciable theta activity was related to the more novel non-target stimuli; primarily target component delta coefficients were affected by the discrimination difficulty variable. The findings suggest that target/standard discrimination difficulty, rather than stimulus novelty, determines P3a generation for visual stimuli but that the underlying theta oscillations are differentially affected by stimulus novelty. WT analysis methods are discussed along with the theoretical and neurophysiological implications of the findings.
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p3a and P3b from typical auditory and visual stimuli
Clinical Neurophysiology, 1999Co-Authors: Marco Comerchero, John PolichAbstract:Objective: Target/standard discrimination difficulty was manipulated systematically to assess how this variable affects target and nontarget P300 scalp distributions for both auditory and visual stimuli. Design and methods: A 3-stimulus paradigm (target, standard, nontarget) was employed in which subjects (n = 16) responded only to an infrequently occurring target stimulus. The perceptual discrimination difficulty between the target and more frequently occurring standard stimuli was varied as Easy or Difficult in different conditions, while holding the nontarget stimulus properties constant. Results: When target/standard discrimination was Easy, P300 amplitude was larger for the target than the nontarget across all electrode sites, and both demonstrated parietal maximums. In contrast, when target/standard discrimination was Difficult, target amplitude (P3b) was larger parietally and occurred later than nontarget components, whereas nontarget amplitude (P3a) was larger and earlier than the target P300 over the frontal electrode sites. Similar outcomes across task conditions were obtained for both auditory and visual stimuli. Conclusions: The findings suggest that target/standard discrimination difficulty, rather than stimulus novelty, determines P3a generation for both auditory and visual stimulus modalities. © 1999 Elsevier Science Ireland Ltd. All rights reserved
Mari Tervaniemi - One of the best experts on this subject based on the ideXlab platform.
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music training enhances the rapid plasticity of p3a P3b event related brain potentials for unattended and attended target sounds
Attention Perception & Psychophysics, 2012Co-Authors: Miia Seppanen, Mari Tervaniemi, Anu-katriina PesonenAbstract:Neurocognitive studies have shown that extensive musical training enhances P3a and P3b event-related potentials for infrequent target sounds, which reflects stronger attention switching and stimulus evaluation in musicians than in nonmusicians. However, it is unknown whether the short-term plasticity of P3a and P3b responses is also enhanced in musicians. We compared the short-term plasticity of P3a and P3b responses to infrequent target sounds in musicians and nonmusicians during auditory perceptual learning tasks. Target sounds, deviating in location, pitch, and duration with three difficulty levels, were interspersed among frequently presented standard sounds in an oddball paradigm. We found that during passive exposure to sounds, musicians had habituation of the P3a, while nonmusicians showed enhancement of the P3a between blocks. Between active tasks, P3b amplitudes for duration deviants were reduced (habituated) in musicians only, and showed a more posterior scalp topography for habituation when compared to P3bs of nonmusicians. In both groups, the P3a and P3b latencies were shortened for deviating sounds. Also, musicians were better than nonmusicians at discriminating target deviants. Regardless of musical training, better discrimination was associated with higher working memory capacity. We concluded that music training enhances short-term P3a/P3b plasticity, indicating training-induced changes in attentional skills.
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Music training enhances the rapid plasticity of P3a/P3b event-related brain potentials for unattended and attended target sounds
Attention Perception & Psychophysics, 2012Co-Authors: Miia Seppanen, Anu-katriina Pesonen, Mari TervaniemiAbstract:Neurocognitive studies have shown that extensive musical training enhances P3a and P3b event-related potentials for infrequent target sounds, which reflects stronger attention switching and stimulus evaluation in musicians than in nonmusicians. However, it is unknown whether the short-term plasticity of P3a and P3b responses is also enhanced in musicians. We compared the short-term plasticity of P3a and P3b responses to infrequent target sounds in musicians and nonmusicians during auditory perceptual learning tasks. Target sounds, deviating in location, pitch, and duration with three difficulty levels, were interspersed among frequently presented standard sounds in an oddball paradigm. We found that during passive exposure to sounds, musicians had habituation of the P3a, while nonmusicians showed enhancement of the P3a between blocks. Between active tasks, P3b amplitudes for duration deviants were reduced (habituated) in musicians only, and showed a more posterior scalp topography for habituation when compared to P3bs of nonmusicians. In both groups, the P3a and P3b latencies were shortened for deviating sounds. Also, musicians were better than nonmusicians at discriminating target deviants. Regardless of musical training, better discrimination was associated with higher working memory capacity. We concluded that music training enhances short-term P3a/P3b plasticity, indicating training-induced changes in attentional skills.
