A5030945577- Motor Control and Adaptation
- Action Observation and Synchronization
- Muscle activation and electromyography studies
- Visual perception and processing mechanisms
- Neural dynamics and brain function
- Neural and Behavioral Psychology Studies
- Robot Manipulation and Learning
- Tactile and Sensory Interactions
- Neurological disorders and treatments
- Functional Brain Connectivity Studies
- Sport Psychology and Performance
- Parkinson's Disease Mechanisms and Treatments
- EEG and Brain-Computer Interfaces
- Neurobiology and Insect Physiology Research
- Multisensory perception and integration
- Photoreceptor and optogenetics research
- Balance, Gait, and Falls Prevention
- Stroke Rehabilitation and Recovery
- Vestibular and auditory disorders
- Conducting polymers and applications
- History of Medical Practice
- Speech and dialogue systems
- Psychosomatic Disorders and Their Treatments
- Neurology and Historical Studies
- Zebrafish Biomedical Research Applications
Columbia University
2018-2024
Brain (Germany)
2019-2021
University of Cambridge
2011-2020
MRC Cognition and Brain Sciences Unit
2018
Sobell House
2004-2008
University College London
2002-2004
Neurology, Inc
2002
Transnational Press London
2002
University of Florence
2002
National Hospital for Neurology and Neurosurgery
2002
Real-world tasks often require movements that depend on a previous action or changes in the state of world. Here we investigate whether motor memories encode current manner depends sensorimotor states. Human subjects performed trials which they made randomly selected clockwise counterclockwise velocity-dependent curl force field. Movements during this adaptation phase were preceded by contextual determined two fields would be experienced any given trial. As expected from research, when...
Abstract The control of voluntary movement changes markedly with age. A critical component motor is the integration sensory information predictions consequences action, arising from internal models movement. This leads to sensorimotor attenuation—a reduction in perceived intensity sensations self-generated compared external actions. Here we show that attenuation occurs 98% adults a population-based cohort ( n =325; 18–88 years; Cambridge Centre for Ageing and Neuroscience). Importantly,...
After committing to an action, a decision-maker can change their mind revise the action. Such changes of even occur when stream information that led action is curtailed at movement onset. This explained by time delays in sensory processing and motor planning which lead component end only be processed after initiation. post-initiation explain pattern asserting accumulation additional evidence criterion level, termed change-of-mind bound. Here we test hypothesis physical effort associated with...
When a part of the body moves, sensation evoked by probe stimulus to that is attenuated. Two mechanisms have been proposed explain this robust and general effect. First, feedforward motor signals may modulate activity incoming sensory signals. Second, reafferent from movements mask stimulus. Here we delivered stimuli right index finger just before cue which instructed subjects make left or movements. cues were equiprobable, found attenuation for was cued (and subsequently moved). However,...
Humans use their arms to engage in a wide variety of motor tasks during everyday life. However, little is known about the statistics these natural arm movements. Studies sensory system have shown that inputs are key determining processing. We hypothesized movements may, similar way, influence performance as measured laboratory-based tasks. developed portable motion-tracking could be worn by subjects they went daily routine outside laboratory setting. found well-documented symmetry bias...
The adaption of movement to changes in the environment varies across life span. Recent evidence has linked motor adaptation and its reduction with age differences "explicit" learning processes. We examine brain structure cognition underlying a population-based cohort (n = 322, aged 18–89 years) using visuomotor task structural magnetic resonance imaging. Reduced was associated reduced volume striatum, prefrontal, sensorimotor cortical regions, but not cerebellum. Medial temporal lobe volume,...
Cognitive decision-making is known to be sensitive the values of potential options, which are probability and size rewards associated with different choices. Here, we examine whether rapid motor responses perturbations visual feedback about movement, mediate low-level involuntary control loops, reflect computations high-level value-based decision-making. In three experiments involving human participants, varied value targets for reaching movements by controlling distributions across...
Motor control strongly relies on neural processes that predict the sensory consequences of self-generated actions. Previous research has demonstrated deficits in such sensory-predictive schizophrenic patients and these low-level are thought to contribute emergence delusions control. Here, we examined extent which individual differences prediction associated with a tendency towards delusional ideation healthy participants. We used force-matching task quantify processes, administered...
Skillful tool use requires knowledge of the dynamic properties tools in order to specify mapping between applied force and motion [1][2][3].Importantly, this depends on orientation hand.Here we investigate representation dynamics during skillful manipulation a that can be grasped at different orientations.We ask whether motor system uses single general for all grasp contexts or it multiple grasp-specific representations.Using novel robotic interface [4], subjects rotated virtual whose...
Human subjects easily adapt to single dynamic or visuomotor perturbations. In contrast, when two opposing perturbations are presented sequentially, interference is often observed. We examined the effect of bimanual movement context on between using pairs contexts, in which relative direction arms was different across pair. When each perturbation associated with a context, such as same versus opposite direction, dramatically reduced. This occurred over short period training and seen for both...
Rhythmic and discrete arm movements occur ubiquitously in everyday life, there is a debate as to whether these two classes of arise from the same or different underlying neural mechanisms. Here we examine interference motor-learning paradigm test rhythmic employ at least partially separate representations. Subjects were required make circular their right hand while they exposed velocity-dependent force field that perturbed circularity movement path. The direction force-field perturbation...
Abnormal initiation and control of voluntary movements are among the principal manifestations Parkinson's disease (PD). However, processes underlying these abnormalities their potential remediation by dopamine treatment remain poorly understood. Normally, depend on integration sensory information with predicted consequences action. This leads to a suppression in intensity sensations, reflected 'sensory attenuation'. We examined this process its relation PD, measuring attenuation. Patients...
Motor imagery, that is the mental rehearsal of a motor skill, can lead to improvements when performing same skill. Here we show powerful and complementary role, in which imagery different movements after actually skill allows learning not possible without imagery. We leverage well-studied task subjects reach presence dynamic (force-field) perturbation. When two opposing perturbations are presented alternately for physical movement, there substantial interference, preventing any learning....
The brain can generate actions, such as reaching to a target, using different movement strategies. We investigate how strategies are learned in task where perched head-fixed mice learn reach an invisible target area from set start position joystick. This be achieved by learning move specific direction or endpoint location. As the they refine their variable joystick trajectories into controlled reaches, which depend on sensorimotor cortex. show that individual biased either direction-...
Making choices is a fundamental aspect of human life. For over century experimental economists have characterized the decisions people make based on concept utility function. This function increases with increasing desirability outcome, and are assumed to so as maximize utility. When depends several variables, indifference curves arise that represent outcomes identical therefore equally desirable. Whereas in economics studied terms goods services, sensorimotor system may also functions...
Current models of motor learning posit that skill acquisition involves both the formation and decay multiple memories can be engaged in different contexts [1Thoroughman K.A. Shadmehr R. Learning action through adaptive combination primitives.Nature. 2000; 407: 742-747Crossref PubMed Scopus (688) Google Scholar, 2Donchin O. Francis J.T. Quantifying generalization from trial-by-trial behavior systems learn with basis functions: theory experiments human control.J. Neurosci. 2003; 23:...
Motor learning has been extensively studied using dynamic (force-field) perturbations. These induce movement errors that result in adaptive changes to the motor commands. Several state-space models have developed explain how trial-by-trial drive progressive adaptation observed such studies. applied involving novel dynamics, which typically occurs over tens hundreds of trials, and appears be mediated by a dual-rate process. In contrast, when manipulating objects with familiar subjects adapt...
Our ability to skillfully manipulate an object often involves the motor system learning compensate for dynamics of object. When two arms learn a single they can act cooperatively, whereas when separate objects control each independently. We examined how transfers between these bimanual contexts by applying force fields arms. In coupled context, dynamic is shared arms, and in uncoupled context are experienced independently arm. composition experiment, we found that subjects had learned were...