Motor Neuroscience Laboratory


Publications





Ohashi H, Ostry DJ (2021) Neural development of speech sensorimotor learning. J Neurosci 41:4023-4035.

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Kumar N, van Vugt FT, Ostry DJ (2021) Recognition memory for human motor learning. Curr Biol 31:1678-1686.
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van Vugt FT, Near J, Hennessy T, Doyon J, Ostry DJ (2020) Early stages of sensorimotor map acquisition: neurochemical signature in primary motor cortex and its relation to functional connectivity. J Neurophysiol 122: 1708–1720.

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Ito T, Bai J, Ostry DJ (2020) Contribution of sensory memory to speech motor learning. J Neurophysiol 124:1103-1109.
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Patri JF, Ostry DJ, Diard J, Schwartz JL, Trudeau-Fisette P, Savariaux C, Perrier P (2020) Speakers are able to categorize vowels based on tongue somatosensation. Proc Natl Acad Sci U S A. 117:6255-6263.
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Darainy M, Vahdat S, Ostry DJ (2019) Neural basis of sensorimotor learning in speech motor adaptation. Cereb Cortex 29:2876-2889.
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Ohashi H, Valle-Mena R, Gribble P, Ostry DJ (2019) Movements following force-field adaptation are aligned with altered sense of limb position. Exp Brain Res 237:1303-1313.
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van Vugt FT, Ostry DJ (2019) Early stages of sensorimotor map acquisition: learning with free exploration, without active movement or global structure. J Neurophysiol 122:1708-1720.
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Kumar N, Manning TF, Ostry DJ (2019) Somatosensory cortex participates in the consolidation of human motor memory. PLoS Biol 17:e3000469.
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Ohashi H, Gribble PL, Ostry DJ (2019) Somatosensory cortical excitability changes precede those in motor cortex during human motor learning. J Neurophysiol 122:1397-1405.
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Darainy M, Vahdat S, Ostry DJ (2019) Neural basis of sensorimotor learning in speech motor adaptation. Cereb Cortex
29:2876-2889.
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Vahdat S, Darainy M, Thiel A, Ostry DJ (2018) A single session of robot-controlled proprioceptive training modulates functional connectivity of sensory motor networks and improves reaching accuracy in chronic stroke.  Neurorehabil Neural Repair 33:70-81.
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Sidarta A, van Vugt FT, Ostry DJ (2018) Somatosensory working memory in human reinforcement-based motor learning. J Neurophysiol 120:3275-3286.
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Bernardi NF, Van Vugt FT, Valle-Mena R, Vahdat S, Ostry DJ (2018) Error-related persistence of motor activity in resting-state networks. J Cogn Neurosci 20:1-19.
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Milner TE, Firouzimehr Z, Babadi S, Ostry DJ (2018) Different adaptation rates to abrupt and gradual changes in environmental dynamics. Exp Brain Res 236:2923-2933.
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Adaptation to an abrupt change in the dynamics of the interaction between the arm and the physical environment has been reported as occurring more rapidly but with less retention than adaptation to a gradual change in interaction dynamics. Faster adaptation to an abrupt change in interaction dynamics appears inconsistent with kinematic error sensitivity which has been shown to be greater for small errors than large errors. However, the comparison of adaptation rates was based on incomplete adaptation. Furthermore, the metric which was used as a proxy of the changing internal state, namely the linear regression between the force disturbance and the compensatory force (the adaptation index), does not distinguish between internal state inaccuracy resulting from amplitude or temporal errors. To resolve the apparent inconsistency, we compared the evolution of the internal state during complete adaptation to an abrupt and gradual change in interaction dynamics. We found no difference in the rate at which the adaptation index increased during adaptation to a gradual compared to an abrupt change in interaction dynamics. In addition, we separately examined amplitude and temporal errors using different metrics, and found that amplitude error was reduced more rapidly under the gradual than the abrupt condition, whereas temporal error (quantified by smoothness) was reduced more rapidly under the abrupt condition. We did not find any significant change in phase lag during adaptation under either condition. Our results also demonstrate that even after adaptation is complete, online feedback correction still plays a significant role in the control of reaching.

Van Vugt FT and Ostry DJ (2018) The structure and acquisition of sensorimotor maps. J Cogn Neurosci 30: 290-306.
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Sidarta A, Vahdat S, Bernardi NF, Ostry DJ (2016) Somatic and reinforcement-based plasticity in the initial stages of human motor learning. J Neurosci 36:11682-11692.
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As one learns to dance or play tennis, the desired somatosensory state is typically unknown. Trial and error is important as motor behavior is shaped by successful and unsuccessful movements. As an experimental model, we designed a task in which human participants make reaching movements to a hidden target and receive positive reinforcement when successful. We identified somatic and reinforcement-based sources of plasticity on the basis of changes in functional connectivity using resting-state fMRI before and after learning. The neuroimaging data revealed reinforcement-related changes in both motor and somatosensory brain areas in which a strengthening of connectivity was related to the amount of positive reinforcement during learning. Areas of prefrontal cortex were similarly altered in relation to reinforcement, with connectivity between sensorimotor areas of putamen and the reward-related ventromedial prefrontal cortex strengthened in relation to the amount of successful feedback received. In other analyses, we assessed connectivity related to changes in movement direction between trials, a type of variability that presumably reflects exploratory strategies during learning. We found that connectivity in a network linking motor and somatosensory cortices increased with trial-to-trial changes in direction. Connectivity varied as well with the change in movement direction following incorrect movements. Here the changes were observed in a somatic memory and decision making network involving ventrolateral prefrontal cortex and second somatosensory cortex. Our results point to the idea that the initial stages of motor learning are not wholly motor but rather involve plasticity in somatic and prefrontal networks related both to reward and exploration.

Ito T, Coppola JH, Ostry DJ (2016) Speech motor learning changes the neural response to both auditory and somatosensory signals. Sci Rep 6:25926
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In the present paper, we present evidence for the idea that speech motor learning is accompanied by changes to the neural coding of both auditory and somatosensory stimuli. Participants in our experiments undergo adaptation to altered auditory feedback, an experimental model of speech motor learning which like visuo-motor adaptation in limb movement, requires that participants change their speech movements and associated somatosensory inputs to correct for systematic real-time changes to auditory feedback. We measure the sensory effects of adaptation by examining changes to auditory and somatosensory event-related responses. We find that adaptation results in progressive changes to speech acoustical outputs that serve to correct for the perturbation. We also observe changes in both auditory and somatosensory event-related responses that are correlated with the magnitude of adaptation. These results indicate that sensory change occurs in conjunction with the processes involved in speech motor adaptation.

Ostry DJ, Gribble PL (2016) Sensory plasticity in human motor learning. Trends Neurosci 39:114-123
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There is accumulating evidence from behavioral, neurophysiological, and neuroimaging studies that the acquisition of motor skills involves both perceptual and motor learning. Perceptual learning alters movements, motor learning, and motor networks of the brain. Motor learning changes perceptual function and the sensory circuits of the brain. Here, we review studies of both human limb movement and speech that indicate that plasticity in sensory and motor systems is reciprocally linked. Taken together, this points to an approach to motor learning in which perceptual learning and sensory plasticity have a fundamental role. Trends Sensorimotor adaptation results in changes to sensory systems and sensory networks in the brain. Perceptual learning modifies sensory systems and directly alters the motor networks of the brain. Perceptual changes associated with sensorimotor adaptation are durable and occur in parallel with motor learning.

Ito T, Ostry DJ, Gracco VL (2015) Somatosensory event-related potentials from orofacial skin stretch stimulation. J Vis Exp e53621-e53621
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Cortical processing associated with orofacial somatosensory function in speech has received limited experimental attention due to the difficulty of providing precise and controlled stimulation. This article introduces a technique for recording somatosensory event-related potentials (ERP) that uses a novel mechanical stimulation method involving skin deformation using a robotic device. Controlled deformation of the facial skin is used to modulate kinesthetic inputs through excitation of cutaneous mechanoreceptors. By combining somatosensory stimulation with electroencephalographic recording, somatosensory evoked responses can be successfully measured at the level of the cortex. Somatosensory stimulation can be combined with the stimulation of other sensory modalities to assess multisensory interactions. For speech, orofacial stimulation is combined with speech sound stimulation to assess the contribution of multi-sensory processing including the effects of timing differences. The ability to precisely control orofacial somatosensory stimulation during speech perception and speech production with ERP recording is an important tool that provides new insight into the neural organization and neural representations for speech.

Bernardi NF, Darainy M, Ostry DJ (2015) Somatosensory contribution to the early stages of motor skill learning. J Neurosci 35: 14316 -14326
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The early stages of motor skill acquisition are often marked by uncertainty about the sensory and motor goals of the task, as is the case in learning to speak or learning the feel of a good tennis serve. Here we present an experimental model of this early learning process, in which targets are acquired by exploration and reinforcement rather than sensory error. We use this model to investigate the relative contribution of motor and sensory factors to human motor learning. Participants make active reaching movements or matched passive movements to an unseen target using a robot arm. We find that learning through passive movements paired ith reinforcement is comparable with learning associated with active movement, both in terms of magnitude and durability, with improvements due to training still observable at a 1 week retest. Motor learning is also accompanied by changes in somatosensory perceptual acuity. No stable changes in motor performance are observed for participants that train, actively or passively, in the absence of reinforcement, or for participants who are given explicit information about target position in the absence of somatosensory experience. These findings indicate that the somatosensory system dominates learning in the early stages of motor skill acquisition.

Lametti DR, Rochet-Capellan A, Neufeld E, Shiller DM, Ostry DJ (2014) Plasticity in the human speech motor system drives changes in speech perception. J Neurosci 34:10339-10346.
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Lametti DR, Krol SA, Shiller DM, Ostry DJ (2014) Brief periods of auditory perceptual training can determine the sensory targets of speech motor learning. Psychol Sci. 25:1325-1336.
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Ito T, Johns AR, Ostry DJ (2014) Left lateralized enhancement of orofacial somatosensory processing due to speech sounds. J Speech Lang Hear Res. 56:1875-81.
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Vahdat S, Darainy M, Ostry DJ (2014) Structure of plasticity in human sensory and motor networks due to perceptual learning. J Neurosci 34:2451-63.
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Darainy M, Vahdat S, Ostry DJ (2013) Perceptual learning in sensorimotor adaptation. J Neurophysiol 110: 2152-2162.
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Bernardi NF, Darainy M, Bricolo E, Ostry DJ (2013) Observing motor learning produces somatosensory change. J Neurophysiol 110: 1804-1810.
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Ito S, Darainy M, Sasaki M, Ostry DJ (2013) Computational model of motor learning and perceptual change. Biol Cybern 107:653-667.
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Nasir SM, Darainy M, Ostry DJ (2013) Sensorimotor adaptation changes the neural coding of somatosensory stimuli. J. Neurophysiol. 109:2077-85.
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Mattar AAG, Darainy M, Ostry DJ (2013) Motor learning and its sensory effects: The time course of perceptual change, and its presence with gradual introduction of load. J. Neurophysiol. 109:782-91.
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Lametti DR, Nasir S, Ostry DJ (2012) Sensory preference in speech production revealed by simultaneous alteration of auditory and somatosensory feedback. J Neurosci 32:9351-9359.
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Rochet-Capellan A, Richer L, Ostry DJ (2012) Non-homogeneous transfer reveals specificity in speech motor learning, J Neurophysiol 107(6):1711-1717.
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Mattar AAG, Nasir SM, Darainy M, Ostry DJ (2011) Sensory change following motor learning. in Green AM, Chapman CE, Kalaska JF and Lepore F (Eds), Progress in Brain Research, Volume 191 (pp 29-42).
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Vahdat S, Darainy M, Milner TE, Ostry DJ (2011) Functionally specific changes in resting-state sensorimotor networks after motor learning. J Neurosci. 31:16907–16915.
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Rochet-Capellan A, Ostry DJ (2011) Simultaneous acquisition of multiple auditory-motor transformations in speech. J Neurosci. 31:2648-2655.
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Ito T, Ostry DJ (2010) Somatosensory contribution to motor learning due to facial skin deformation. J Neurophysiol 104:1230-1230.
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Lametti DR, Ostry DJ (2010) Postural constraint on movement variability. J Neurophysiol 104:1061-1067.
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Mattar AAG, Ostry DJ (2010) Generalization of dynamics learning across changes in movement amplitude. J Neurophysiol 104:426-438.
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Ostry DJ, Darainy M, Mattar AAG, Wong J, Gribble PL (2010) Somatosensory plasticity and motor learning. J Neurosci 30:5384-5393.
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Nasir SM, Ostry DJ (2009) Auditory plasticity and speech motor learning. Proc Natl Acad Sci U S A 106:20470–20475.
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Laboissière R, Lametti DR, Ostry DJ (2009) Impedance control and its relation to precision in orofacial movement. J Neurophysiol 102:523-531.
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Darainy M, Mattar AAG, Ostry DJ (2009) Effects of human arm impedance on dynamics learning and generalization. J Neurophysiol 101:3158–3168.
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Ito T, Tiede M, Ostry DJ (2009) Somatosensory function in speech perception. Proc Natl Acad Sci U S A 106:1245–1248.
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Nasir SM, Ostry DJ (2008) Speech motor learning in profoundly deaf adults. Nat Neurosci 11:1217–1222.
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Darainy M, Ostry DJ (2008) Muscle cocontraction following dynamics learning. Exp Brain Res 190:153-163.
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Andres M, Ostry DJ, Nicol F, Paus T (2008) Time course of number magnitude interference during grasping. Cortex 44:414-419.
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Tremblay S, Houle G, Ostry DJ (2008) Specificity of speech motor learning. J Neurosci 28:2426–2434.
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The idea that the brain controls movement using a neural representation of limb dynamics has been a dominant hypothesis in motor control research for well over a decade. Speech movements offer an unusual opportunity to test this proposal by means of an examination of transfer of learning between utterances that are to varying degrees matched on kinematics. If speech learning results in a generalizable dynamics representation, then, at the least, learning should transfer when similar movements are embedded in phonetically distinct utterances. We tested this idea using three different pairs of training and transfer utterances that substantially overlap kinematically. We find that, with these stimuli, speech learning is highly contextually sensitive and fails to transfer even to utterances that involve very similar movements. Speech learning appears to be extremely local, and the specificity of learning is incompatible with the idea that speech control involves a generalized dynamics representation.

Darainy M, Towhidkhah F, Ostry DJ (2007) Control of hand impedance under static conditions and during reaching movement. J Neurophysiol 97:2676–2685.
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Lametti DR, Houle G, Ostry DJ (2007) Control of movement variability and the regulation of limb impedance. J Neurophysiol 98:3516-3524.
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Mattar AAG, Ostry DJ (2007) Neural averaging in motor learning. J Neurophysiol 97:220-228.
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Mattar AAG, Ostry DJ (2007) Modifiability of generalization in dynamics learning. J Neurophysiol 98:3321-3329.
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Nasir SM, Ostry DJ (2006) Somatosensory precision in speech production. Curr Biol 16:1918–1923.
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Darainy M, Malfait N, Towhidkhah F, Ostry DJ (2006) Transfer and durability of acquired patterns of human arm stiffness. Exp Brain Res 170:227-237.
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Shiller DM, Houle G, Ostry DJ (2005) Voluntary control of human jaw stiffness. J Neurophysiol 94:2207-2217.
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Malfait N, Gribble PL, Ostry DJ (2005) Generalization of motor learning based on multiple field exposures and local adaptation. J Neurophysiol 93:3327-3338.
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Della-Maggiore V, Malfait N, Ostry DJ, Paus T (2004) Stimulation of the posterior parietal cortex interferes with arm trajectory adjustments during the learning of new dynamics. J Neurosci 24:9971-9976.
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Darainy M, Malfait N, Gribble PL, Towhidkhah F, Ostry DJ (2004) Learning to control arm stiffness under static conditions. J Neurophysiol 92:3344-3350.
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Malfait N, Ostry DJ (2004) Is interlimb transfer of force-field adaptation a "cognitive" response to the sudden introduction of load? J Neurosci 24:8084-8089.
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Petitto LA, Holowka S, Sergio LE, Levy B, Ostry DJ (2004) Baby hands that move to the rhythm of language: hearing babies acquiring sign languages babble silently on the hands. Cognition 93:43-73.
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Ostry DJ, Feldman AG (2003) A critical evaluation of the force control hypothesis in motor control. Exp Brain Res 221:275-288.
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Tremblay S, Shiller DM,Ostry DJ (2003) Somatosensory basis of speech production. Nature 423:866-869.
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Malfait N, Shiller DM, Ostry DJ (2002) Transfer of motor learning across arm configurations. J Neurosci 22:9656-9660.
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Shiller DM, Laboissière R, Ostry DJ (2002) The relationship between jaw stiffness and kinematic variability in speech. J Neurophysiol 88:2329-2340.
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Shiller DM, Ostry DJ, Gribble PL, Laboissière R (2001) Compensation for the effects of head acceleration on jaw movement in speech. J Neurosci 21:6447-6456.
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Petitto LA, Holowka S, Sergio LE, Ostry DJ (2001) Language rhythms in baby hand movements. Nature 413:35-36.
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Suzuki M, Shiller DM, Gribble PL, Ostry DJ (2001) Relationship between cocontraction, movement kinematics and phasic muscle activity in single-joint arm movement. Exp Brain Res 140:171-181.
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Ostry DJ, Romo R (2001) Tactile shape processing. Neuron 31:173-174.
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Gribble PL, Ostry DJ (2000) Compensation for loads during arm movements using equilibrium-point control. Exp Brain Res 135:474-482.
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Gribble PL, Ostry DJ (1999) Compensation for interaction torques during single- and multijoint limb movements. J Neurophysiol 82:2310-2326.
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Shiller DM, Ostry DJ, Gribble PL (1999) Effects of gravitational load on jaw movements in speech. J Neurosci 19:9073-9080.
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Gribble PL, Ostry DJ (1998) Independent coactivation of shoulder and elbow muscles. Exp Brain Res 123:355-360.
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Feldman AG, Ostry DJ, Levin MF, Gribble PL, Mitnitski A (1998) Recent tests of the equilibrium point hypothesis. Motor Control 2:189-205.
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Gribble PL, Ostry DJ, Sanguineti V, Laboissière R (1998) Are complex control signals required for human arm movement? J Neurophysiol 79:1409-1424.
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Sanguineti V, Laboissière R, Ostry DJ (1998) A dynamic biomechanical model for neural control of speech production. J Acoust Soc Am 103:1615-1627.
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Guiard-Marigny T, Ostry DJ (1997) A system for three-dimensional visualization of human jaw motion in speech. J Speech Lang Hear Res 40:1118-1121.
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Ostry DJ, Vatikiotis-Bateson E, Gribble PL (1997) An examination of the degrees of freedom of human jaw motion in speech and mastication. J Speech Lang Hear Res 40:1341-1351.
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Ostry DJ, Gribble PL, Levin MF, Feldman AG (1997) Phasic and tonic stretch reflexes in muscles with few muscles spindles: human jaw-opener muscles. Exp Brain Res 116:299-308.
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Gribble PL, Ostry DJ (1996) Origins of the power law relation between movement velocity and curvature: modeling the effects of muscle mechanics and limb dynamics. J Neurophysiol 76:2853-2860.
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Ramsay JO, Munhall KG, Gracco VL, Ostry DJ (1996) Functional data analyses of lip motion. J Acoust Soc Am 99:3718-3727.
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Laboissière R, Ostry DJ, Feldman AG (1996) The control of multi-muscle systems: human jaw and hyoid movements. Biol Cybern 74:373-384.
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Ostry DJ, Gribble PL, Gracco VL (1996) Coarticulation of jaw movements in speech production: is context sensitivity in speech kinematics centrally planned? J Neurosci 16:1570-1579.
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Bonda E, Petrides M, Ostry DJ, Evans A (1996) Specific involvement of human parietal systems and the amygdala in the perception of biological motion. J Neurosci 16:3737-3744.
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Perrier P, Ostry DJ, Laboissière R (1996) The equilibrium point hypothesis and its application to speech motor control. J Speech Hear Res 39:365-377.
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Sergio LE, Ostry DJ (1995) Coordination of multiple muscles in two degree of freedom elbow movements. Exp Brain Res 105:123-137.
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Bateson EV, Ostry DJ (1995) An analysis of the dimensionality of jaw movement in speech. J Phon 23:101-117.
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Ostry DJ, Munhall KG (1994) Control of jaw orientation and position in mastication and speech. J Neurophysiol 71:1528-1545.
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Sergio LE, Ostry DJ (1994) Coordination of mono- and bi- articular muscles in multi-degree of freedom elbow movements. Exp Brain Res 97:551-555.
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Parush A, Ostry DJ (1993) Lower pharyngeal wall coarticulation in VCV syllables. J Acoust Soc Am 94:715-22.
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Sergio LE, Ostry DJ (1993) Three-dimensional kinematic analysis of frog hindlimb movement in reflex wiping. Exp Brain Res 94:53-64.
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Ostry DJ, Feldman AG, Flanagan JR (1991) Kinematics and control of frog hindlimb movements. J Neurophysiol 65:547-562.
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Ostry DJ, Flanagan JR (1989) Human jaw movement in mastication and speech. Arch Oral Biol 34:685-693.
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Ostry DJ, Cooke JD, Munhall KG (1987) Velocity curves of human arm and speech movements. Exp Brain Res 68:37-46.
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Parush A, Ostry DJ (1986) Superior lateral pharyngeal wall movements in speech. J Acoust Soc Am 80:749-756.
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Munhall KG, Ostry DJ, Parush A (1985) Characteristics of velocity profiles of speech movements. J Exp Psychol Hum Percept Perform 11:457-474.
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Ostry DJ, Munhall KG (1985) Control of rate and duration of speech movements. J Acoust Soc Am 77:640-648.
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Parush A, Ostry DJ, Munhall KG (1983) A kinematic study of lingual coarticulation in VCV sequences. J Acoust Soc Am 74:1115-1125.
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Ostry DJ, Keller E, Parush A (1983) Similarities in the control of the speech articulators and the limbs: kinematics of tongue dorsum movement in speech. J Exp Psychol Hum Percept Perform 9:622-636.
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Keller E, Ostry DJ (1983) Computerized measurement of tongue dorsum movements with pulsed-echo ultrasound. J Acoust Soc Am 73:1309-1315.
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Ostry DJ (1983) Determinants of interkey times in typing. In W. E. Cooper (ed.), Cognitive Aspects of Skilled Typewriting, Springer-Verlag New York Inc.
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Typewriting, musical instrument playing, spoken language, and dance involve sophisticated motor skills and associated symbol schemes. Researchers in cognition have been interested in these abilities because they enable the study of relations between the structure of motor behavior and the organization of the associated formal system. Typewriting, in particular, is of interest because of the remarkable rate and complexity of finger and hand movements involved and because its performance is readily quantifiable. However, if typewriting is to be used to study either cognitive or motor organization, the factors contributing to its temporal structure must be identified. In this chapter I present the findings of several studies that examine variables that influence the pattern of interkey times in typing. In addition to providing evidence on the constituents of control in typing, the studies provide a basis for the examination of proposals by Ostry (1980) and Sternberg, Monsell, Knoll, and Wright (1978) that certain aspects of typing control are inherently tied to the execution of the sequence. The suggestions arise from observations that patterns of initial latency and interkey time are not changed by the introduction of a delay between stimulus presentation and a response signal. The inability to take advantage of a preparation interval seems to indicate that the programming of typing movements is intimately linked to their execution.