Peter Q Pfordresher

Publications of Peter Q Pfordresher

• Correction to pfordresher and kulpa (2011).

  Authors: Peter Q Pfordresher, J D Kulpa

  Journal of experimental psychology. Human perception and performance. 12/2011; 37(6):1699.

  Reports an error in "The dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and timing" by Peter Q. Pfordresher and J. D. Kulpa (Journal ofReports an error in "The dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and timing" by Peter Q. Pfordresher and J. D. Kulpa (Journal of Experimental Psychology: Human Perception and Performance, 2011[Jun], Vol 37[3], 949-967). In Figure 8 the y-axes for panels A, B, C, and D should read "Mean error rate" instead of "Mean IRI." In addition, in the caption for Figure 8 the sentence "Each data point represents the mean error rate across participants beginning at that serial position, ending at the next serial position" should read "Each data point represents the mean error rate across participants at that serial position." (The following abstract of the original article appeared in record 2011-07484-001.) Three experiments were designed to test whether perception and action are coordinated in a way that distinguishes sequencing from timing (Pfordresher, 2003). Each experiment incorporated a trial design in which altered auditory feedback (AAF) was presented for varying lengths of time and then withdrawn. Experiments 1 and 2 included AAF that resulted in action-effect asynchronies (delayed auditory feedback) during simple tapping (Experiment 1) and melody production (Experiment 2). Asynchronous AAF immediately slowed production; this effect then diminished rapidly after removal of AAF. By contrast, sequential alterations of feedback pitch during melody production (Experiment 3) had an effect that varied over successive presentations of AAF (by increasing error rates) that lasted after its withdrawal. The presence of auditory feedback after withdrawal of asynchronous AAF (Experiments 1 and 2) led to overcompensation of timing, whereas the presence of auditory feedback did not influence performance after withdrawal of AAF in Experiment 3. Based on these results, we suggest that asynchronous AAF perturbs the phase of an internal timekeeper, whereas alterations to feedback pitch over time degrade the internal representation of sequence structure. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

• The experience of agency in sequence production with altered auditory feedback.

  Authors: Justin J Couchman, Robertson Beasley, Peter Q Pfordresher

  Consciousness and cognition. 11/2011; 21(1):186-203.

  When speaking or producing music, people rely in part on auditory feedback - the sounds associated with the performed action. Three experiments investigated the degree to which alterations ofWhen speaking or producing music, people rely in part on auditory feedback - the sounds associated with the performed action. Three experiments investigated the degree to which alterations of auditory feedback (AAF) during music performances influence the experience of agency (i.e., the sense that your actions led to auditory events) and the possible link between agency and the disruptive effect of AAF on production. Participants performed short novel melodies from memory on a keyboard. Auditory feedback during performances was manipulated with respect to its pitch contents and/or its synchrony with actions. Participants rated their experience of agency after each trial. In all experiments, AAF reduced judgments of agency across conditions. Performance was most disrupted (measured by error rates and slowing) when AAF led to an ambiguous experience of agency, suggesting that there may be some causal relationship between agency and disruption. However, analyses revealed that these two effects were probably independent. A control experiment verified that performers can make veridical judgments of agency.

• The dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and timing.

  Authors: Peter Q Pfordresher, J D Kulpa

  Journal of experimental psychology. Human perception and performance. 06/2011; 37(3):949-67.

  Three experiments were designed to test whether perception and action are coordinated in a way that distinguishes sequencing from timing (Pfordresher, 2003). Each experiment incorporated a trialThree experiments were designed to test whether perception and action are coordinated in a way that distinguishes sequencing from timing (Pfordresher, 2003). Each experiment incorporated a trial design in which altered auditory feedback (AAF) was presented for varying lengths of time and then withdrawn. Experiments 1 and 2 included AAF that resulted in action-effect asynchronies (delayed auditory feedback) during simple tapping (Experiment 1) and melody production (Experiment 2). Asynchronous AAF immediately slowed production; this effect then diminished rapidly after removal of AAF. By contrast, sequential alterations of feedback pitch during melody production (Experiment 3) had an effect that varied over successive presentations of AAF (by increasing error rates) that lasted after its withdrawal. The presence of auditory feedback after withdrawal of asynchronous AAF (Experiments 1 and 2) led to overcompensation of timing, whereas the presence of auditory feedback did not influence performance after withdrawal of AAF in Experiment 3. Based on these results, we suggest that asynchronous AAF perturbs the phase of an internal timekeeper, whereas alterations to feedback pitch over time degrade the internal representation of sequence structure.

• Delayed auditory feedback and movement.

  Authors: Peter Q Pfordresher, Simone Dalla Bella

  Journal of experimental psychology. Human perception and performance. 04/2011; 37(2):566-79.

  It is well known that timing of rhythm production is disrupted by delayed auditory feedback (DAF), and that disruption varies with delay length. We tested the hypothesis that disruption depends onIt is well known that timing of rhythm production is disrupted by delayed auditory feedback (DAF), and that disruption varies with delay length. We tested the hypothesis that disruption depends on the state of the movement trajectory at the onset of DAF. Participants tapped isochronous rhythms at a rate specified by a metronome while hearing DAF (for piano tones) of differing lengths. Motion capture was used to analyze movement trajectories. Mean Inter-Response Intervals (IRIs) varied as an approximately sinusoidal function of feedback condition, with DAF causing slowed production for shorter delays and speeded production for faster delays. Motion capture analyses revealed that finger velocity at the time of DAF predicted the effect of DAF on mean IRI whereas finger position predicted the variability of IRIs. A second experiment in which participants were instructed to vary the timing of peak finger height confirmed that the effect of DAF on timing variability is directly influenced by the finger trajectory.

• Activation of learned action sequences by auditory feedback.

  Authors: Peter Q Pfordresher, Peter E Keller, Iring Koch, Caroline Palmer, Ece Yildirim

  Psychonomic bulletin & review. 03/2011; 18(3):544-9.

  The present research addressed whether auditory feedback associated with a learned action sequence can activate the action representation of that sequence. Nonpianist participants learned to performThe present research addressed whether auditory feedback associated with a learned action sequence can activate the action representation of that sequence. Nonpianist participants learned to perform two melodies at a piano keyboard repeatedly during a trial. The participants heard feedback either from the melody they were performing (normal feedback) or from the other learned melody (termed alternate feedback). An additional tone functioned as an instruction cue to either switch melodies or continue the current melody. Following the instruction cues, participants typically paused just before switching, and paused similarly during trials with a continue cue. Participants paused longer after a continue cue when they experienced alternate rather than normal feedback. This effect was specific to instruction cues positioned at weak metrical accents--positions at which participants were less likely to switch overall. Feedback did not influence timing on switch trials. These findings indicate that influences of auditory feedback can activate learned action sequences, leading to longer latencies associated with cue evaluation.

• Imprecise singing is widespread.

  Authors: Peter Q Pfordresher, Steven Brown, Kimberly M Meier, Michel Belyk, Mario Liotti

  The Journal of the Acoustical Society of America. 10/2010; 128(4):2182-90.

  There has been a recent surge of research on the topic of poor-pitch singing. However, this research has not addressed an important distinction in measurement: that between accuracy and precision.There has been a recent surge of research on the topic of poor-pitch singing. However, this research has not addressed an important distinction in measurement: that between accuracy and precision. With respect to singing, accuracy refers to the average difference between sung and target pitches. Precision, by contrast, refers to the consistency of repeated attempts to produce a pitch. A group of 45 non-musician participants was asked to vocally imitate unfamiliar 5-note melodies, as well as to sing a series of familiar melodies from memory (e.g., Happy Birthday). The results showed that singers were more accurate than they were precise, and that a majority of participants could justifiably be categorized as imprecise singers. Accuracy and precision measures were correlated with one another, and conditional-probability analyses suggested that accuracy predicted precision more so than the converse. Finally, performance differences across groups of singers were greater for the imitation of unfamiliar tone sequences than for the recall of familiar melodies.

• Enhanced production and perception of musical pitch in tone language speakers.

  Authors: Peter Q Pfordresher, Steven Brown

  Attention, perception & psychophysics. 09/2009; 71(6):1385-98.

  Individuals differ markedly with respect to how well they can imitate pitch through singing and in their ability to perceive pitch differences. We explored whether the use of pitch in one's nativeIndividuals differ markedly with respect to how well they can imitate pitch through singing and in their ability to perceive pitch differences. We explored whether the use of pitch in one's native language can account for some of the differences in these abilities. Results from two studies suggest that individuals whose native language is a tone language, in which pitch contributes to word meaning, are better able to imitate (through singing) and perceptually discriminate musical pitch. These findings support the view that language acquisition fine-tunes the processing of critical auditory dimensions in the speech signal and that this fine-tuning can be carried over into nonlinguistic domains.

• The somatotopy of speech: Phonation and articulation in the human motor cortex.

  Authors: Steven Brown, Angela R Laird, Peter Q Pfordresher, Sarah M Thelen, Peter Turkeltaub, Mario Liotti

  Brain and cognition. 02/2009;

  A sizable literature on the neuroimaging of speech production has reliably shown activations in the orofacial region of the primary motor cortex. These activations have invariably been interpreted asA sizable literature on the neuroimaging of speech production has reliably shown activations in the orofacial region of the primary motor cortex. These activations have invariably been interpreted as reflecting "mouth" functioning and thus articulation. We used functional magnetic resonance imaging to compare an overt speech task with tongue movement, lip movement, and vowel phonation. The results showed that the strongest motor activation for speech was the somatotopic larynx area of the motor cortex, thus reflecting the significant contribution of phonation to speech production. In order to analyze further the phonatory component of speech, we performed a voxel-based meta-analysis of neuroimaging studies of syllable-singing (11 studies) and compared the results with a previously-published meta-analysis of oral reading (11 studies), showing again a strong overlap in the larynx motor area. Overall, these findings highlight the under-recognized presence of phonation in imaging studies of speech production, and support the role of the larynx motor cortex in mediating the "melodicity" of speech.

• Auditory feedback in music performance: the role of transition-based similarity.

  Authors: Peter Q Pfordresher

  Journal of experimental psychology. Human perception and performance. 06/2008; 34(3):708-25.

  Past research has suggested that the disruptive effect of altered auditory feedback depends on how structurally similar the sequence of feedback events is to the planned sequence of actions. ThreePast research has suggested that the disruptive effect of altered auditory feedback depends on how structurally similar the sequence of feedback events is to the planned sequence of actions. Three experiments pursued one basis for similarity in musical keyboard performance: matches between sequential transitions in spatial targets for movements and the melodic contour of auditory feedback. Trained pianists and musically untrained persons produced simple tonal melodies on a keyboard while hearing feedback sequences that either matched the planned melody or were contour-preserving variations of that melody. Sequence production was disrupted among pianists when feedback events were serially shifted by one event, similarly for shifts of planned melodies and tonal variations but less so for shifts of atonal variations. Nonpianists were less likely to be disrupted by serial shifts of variations but showed similar disruption to pianists for shifts of the planned melody. Thus, transitional properties and tonal schemata may jointly determine perception-action similarity during musical sequence production, and the tendency to generalize from a planned sequence to variations of it may develop with the acquisition of skill.

• Temporal coordination between actions and sound during sequence production.

  Authors: Peter Q Pfordresher, Brian Benitez

  Human movement science. 11/2007; 26(5):742-56.

  Delayed auditory feedback (DAF) causes asynchronies between perception and action that disrupt sequence production. Different delay lengths cause differing amounts of disruption that may reflect theDelayed auditory feedback (DAF) causes asynchronies between perception and action that disrupt sequence production. Different delay lengths cause differing amounts of disruption that may reflect the phase location of feedback onsets relative to produced inter-response intervals, or the absolute temporal separation between actions and sounds. Two experiments addressed this issue by comparing the effects of traditional DAF, which uses a constant temporal separation, with delays that adjust temporal separation to maintain the phase location of feedback onsets within inter-response intervals. Participants played simple isochronous melodies on a keyboard, or tapped an isochronous beat, at three production rates. Disruption was best predicted by the phase location of feedback onsets, and diminished when feedback onsets formed harmonic phase ratios (phase synchrony). Both delay types led to similar effects. Different movement tasks (melody production versus tapping) led to slightly different patterns of disruption across phase that may relate to differing task demands. In general, these results support the view that perception and action are coordinated in relative rather than absolute time.

• Speed, accuracy, and serial order in sequence production.

  Authors: Peter Q Pfordresher, Caroline Palmer, Melissa K Jungers

  Cognitive science. 02/2007; 31(1):63-98.

  The production of complex sequences like music or speech requires the rapid and temporally precise production of events (e.g., notes and chords), often at fast rates. Memory retrieval in theseThe production of complex sequences like music or speech requires the rapid and temporally precise production of events (e.g., notes and chords), often at fast rates. Memory retrieval in these circumstances may rely on the simultaneous activation of both the current event and the surrounding context (Lashley, 1951). We describe an extension to a model of incremental retrieval in sequence production (Palmer & Pfordresher, 2003) that incorporates this logic to predict overall error rates and speed-accuracy trade-offs, as well as types of serial ordering errors. The model-assumes that retrieval of the current event is influenced by activations of surrounding events. Activations of surrounding events increase over time, such that both the accessibility of distant events and overall accuracy increases at slower production rates. The model's predictions were tested in an experiment in which pianists performed unfamiliar music at 8 different tempi. Model fits to speed-accuracy data and to serial ordering errors support model predictions. Parameter fits to individual data further suggest that working memory contributes to the retrieval of serial order and overall accuracy is influenced in addition by motor dexterity and domain-specific skill.

• Effects of hearing the past, present, or future during music performance.

  Authors: Peter Q Pfordresher, Caroline Palmer

  Perception & psychophysics. 04/2006; 68(3):362-76.

  Three experiments were performed to explore the effects of mismatches between actions (key-presses) and the contents of auditory feedback (pitch events) during music performance. Pianists performedThree experiments were performed to explore the effects of mismatches between actions (key-presses) and the contents of auditory feedback (pitch events) during music performance. Pianists performed melodies from memory during altered auditory feedback that was synchronized with key-presses but matched the pitch of other sequence events. Feedback direction was manipulated by presenting pitches that matched events intended for the past (delays; Experiments 1 and 3) or the future (prelays; Experiments 2 and 3). Feedback distance was manipulated by varying the absolute separation between the current event and the location of the feedback pitch. All alterations disrupted the accuracy of performance (pitch errors) more so than timing. Serial-ordering errors indicated confusions among proximal and metrically similar events, consistent with the predictions of an incremental planning model (Palmer & Pfordresher, 2003). Patterns of serial-ordering errors suggested that performers compensate for the disruptive effects of altered feedback by changing event activations during planning.

• Auditory feedback in music performance: the role of melodic structure and musical skill.

  Authors: Peter Q Pfordresher

  Journal of experimental psychology. Human perception and performance. 01/2006; 31(6):1331-45.

  Five experiments explored whether fluency in musical sequence production relies on matches between the contents of auditory feedback and the planned outcomes of actions. Participants performed shortFive experiments explored whether fluency in musical sequence production relies on matches between the contents of auditory feedback and the planned outcomes of actions. Participants performed short melodies from memory on a keyboard while musical pitches that sounded in synchrony with each keypress (feedback contents) were altered. Results indicated that altering pitch contents can disrupt production, but only when altered pitches form a sequence that is structurally similar to the planned sequence. These experiments also addressed the role of musical skill: Experiments 1 and 3 included trained pianists; other experiments included participants with little or no musical training. Results were similar across both groups with respect to the disruptive effects of auditory feedback manipulations. These results support the idea that a common hierarchical representation guides sequences of actions and the perception of event sequences and that this coordination is not acquired from learned associations formed by musical skill acquisition.

• Coordination of perception and action in music performance

  Authors: Peter Q. Pfordresher

  Advances in Cognitive Psychology. 01/2006;

  This review summarizes recent research on the way in which music performance may rely on the perception of sounds that accompany actions (termed auditory feedback). Alterations of auditory feedbackThis review summarizes recent research on the way in which music performance may rely on the perception of sounds that accompany actions (termed auditory feedback). Alterations of auditory feedback can profoundly disrupt performance, though not all alterations cause disruption and different alterations generate different types of disruption. Recent results have revealed a basic distinction between the role of feedback contents (musical pitch) and the degree to which feedback onsets are synchronized with actions. These results further suggest a theoretical framework for the coordination of actions with feedback in which perception and action share a common representation of sequence structure.

• Auditory feedback in music performance: Evidence for a dissociation of sequencing and timing.

  Authors: Peter Q Pfordresher

  Journal of experimental psychology. Human perception and performance. 11/2003; 29(5):949-64.

  Four experiments examined temporal relationships between actions and auditory feedback in music performance. Experiment 1 incorporated phase shifts of feedback, which disrupted produced timing butFour experiments examined temporal relationships between actions and auditory feedback in music performance. Experiment 1 incorporated phase shifts of feedback, which disrupted produced timing but not overall accuracy. Experiment 2 incorporated period shifts of pitch contents for synchronized feedback that primarily disrupted accuracy more than timing. Experiment 3 incorporated combined phase and period shifts, which caused moderate disruption to timing and accuracy and revealed interactive effects of period and phase shifts on production. A 4th experiment included all feedback conditions in the same session to confirm differences across Experiments 1-3. These results are consistent with the view that actions and their perceptual consequences are coordinated in a way that distinguishes timing (phase shifts) from sequencing (period shifts). ((c) 2003 APA, all rights reserved)

• Incremental planning in sequence production.

  Authors: Caroline Palmer, Peter Q Pfordresher

  Psychological review. 11/2003; 110(4):683-712.

  People produce long sequences such as speech and music with incremental planning: mental preparation of a subset of sequence events. The authors model in music performance the sequence events thatPeople produce long sequences such as speech and music with incremental planning: mental preparation of a subset of sequence events. The authors model in music performance the sequence events that can be retrieved and prepared during production. Events are encoded in terms of their serial order and timing relative to other events in a planning increment, a contextually determined distribution of event activations. Planning is facilitated by events' metrical similarity and serial/temporal proximity and by developmental changes in short-term memory. The model's predictions of larger planning increments as production rate decreases and as producers' age-experience increases are confirmed in serial-ordering errors produced by adults and children. Incremental planning is considered as a general retrieval constraint in serially ordered behaviors.

• The somatotopy of speech: Phonation and articulation in the human motor cortex

  Authors: Steven Brown, Angela R. Laird, Peter Q. Pfordresher, Sarah M. Thelen, Peter Turkeltaub, Mario Liotti

  Brain and Cognition.

  A sizable literature on the neuroimaging of speech production has reliably shown activations in the orofacial region of the primary motor cortex. These activations have invariably been interpreted asA sizable literature on the neuroimaging of speech production has reliably shown activations in the orofacial region of the primary motor cortex. These activations have invariably been interpreted as reflecting “mouth” functioning and thus articulation. We used functional magnetic resonance imaging to compare an overt speech task with tongue movement, lip movement, and vowel phonation. The results showed that the strongest motor activation for speech was the somatotopic larynx area of the motor cortex, thus reflecting the significant contribution of phonation to speech production. In order to analyze further the phonatory component of speech, we performed a voxel-based meta-analysis of neuroimaging studies of syllable-singing (11 studies) and compared the results with a previously-published meta-analysis of oral reading (11 studies), showing again a strong overlap in the larynx motor area. Overall, these findings highlight the under-recognized presence of phonation in imaging studies of speech production, and support the role of the larynx motor cortex in mediating the “melodicity” of speech.