Motor representations and the perception of space:

AbstractMotor theories of perception posit that motor information is necessary for successful recognition of actions. Perhaps the most well known of this class of proposals is the motor theory of speech perception, which argues that speech recognition is fundamentally a process of identifying the articulatory gestures (i.e. motor representations) that were used to produce the speech signal. Here we review neuropsychological evidence from patients with damage to the motor system, in the context of motor theories of perception applied to both manual actions and speech. Motor theories of perception predict that patients with motor impairments will have impairments for action recognition. Contrary to that prediction, the available neuropsychological evidence indicates that recognition can be spared despite profound impairments to production. These data falsify strong forms of the motor theory of perception, and frame new questions about the dynamical interactions that govern how information is exchanged between input and output systems.

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Wrist and finger motor representations embedded in the cerebral and cerebellar resting-state activation

Brain Structure and Function ◽

10.1007/s00429-021-02330-8 ◽

2021 ◽

Author(s):

Toshiki Kusano ◽

Hiroki Kurashige ◽

Isao Nambu ◽

Yoshiya Moriguchi ◽

Takashi Hanakawa ◽

...

Keyword(s):

Resting State ◽

Brain Activity ◽

Body Part ◽

Resting State Fmri ◽

Body Parts ◽

Finger Movements ◽

Multiple Components ◽

Brain Activity Pattern ◽

Motor Representations ◽

The Brain

AbstractSeveral functional magnetic resonance imaging (fMRI) studies have demonstrated that resting-state brain activity consists of multiple components, each corresponding to the spatial pattern of brain activity induced by performing a task. Especially in a movement task, such components have been shown to correspond to the brain activity pattern of the relevant anatomical region, meaning that the voxels of pattern that are cooperatively activated while using a body part (e.g., foot, hand, and tongue) also behave cooperatively in the resting state. However, it is unclear whether the components involved in resting-state brain activity correspond to those induced by the movement of discrete body parts. To address this issue, in the present study, we focused on wrist and finger movements in the hand, and a cross-decoding technique trained to discriminate between the multi-voxel patterns induced by wrist and finger movement was applied to the resting-state fMRI. We found that the multi-voxel pattern in resting-state brain activity corresponds to either wrist or finger movements in the motor-related areas of each hemisphere of the cerebrum and cerebellum. These results suggest that resting-state brain activity in the motor-related areas consists of the components corresponding to the elementary movements of individual body parts. Therefore, the resting-state brain activity possibly has a finer structure than considered previously.

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Implicit Motor Imagery and the Lateral Occipitotemporal Cortex: Hints for Tailoring Non-Invasive Brain Stimulation

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17165851 ◽

2020 ◽

Vol 17 (16) ◽

pp. 5851 ◽

Cited By ~ 1

Author(s):

Massimiliano Conson ◽

Roberta Cecere ◽

Chiara Baiano ◽

Francesco De Bellis ◽

Gabriela Forgione ◽

...

Keyword(s):

Motor Imagery ◽

Brain Stimulation ◽

Repetitive Transcranial Magnetic Stimulation ◽

Dominant Hand ◽

Non Invasive ◽

Implicit Motor ◽

Left And Right ◽

Occipitotemporal Cortex ◽

Biomechanical Effect ◽

Motor Representations

Background: Recent evidence has converged in showing that the lateral occipitotemporal cortex is over-recruited during implicit motor imagery in elderly and in patients with neurodegenerative disorders, such as Parkinson’s disease. These data suggest that when automatically imaging movements, individuals exploit neural resources in the visual areas to compensate for the decline in activating motor representations. Thus, the occipitotemporal cortex could represent a cortical target of non-invasive brain stimulation combined with cognitive training to enhance motor imagery performance. Here, we aimed at shedding light on the role of the left and right lateral occipitotemporal cortex in implicit motor imagery. Methods: We applied online, high-frequency, repetitive transcranial magnetic stimulation (rTMS) over the left and right lateral occipitotemporal cortex while healthy right-handers judged the laterality of hand images. Results: With respect to the sham condition, left hemisphere stimulation specifically reduced accuracy in judging the laterality of right-hand images. Instead, the hallmark of motor simulation, i.e., the biomechanical effect, was never influenced by rTMS. Conclusions: The lateral occipitotemporal cortex seems to be involved in mental representation of the dominant hand, at least in right-handers, but not in reactivating sensorimotor information during simulation. These findings provide useful hints for developing combined brain stimulation and behavioural trainings to improve motor imagery.

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Effects of model types in observational learning on implicit sequential learning

Quarterly Journal of Experimental Psychology ◽

10.1080/17470218.2017.1342672 ◽

2018 ◽

Vol 71 (7) ◽

pp. 1596-1606

Author(s):

Kanji Tanaka ◽

Katsumi Watanabe

Keyword(s):

Reaction Time ◽

Action Observation ◽

Reaction Time Task ◽

Test Session ◽

Sequential Learning ◽

Test Sequence ◽

Learning Effects ◽

Behavior Type ◽

Movie Clip ◽

Motor Representations

This study investigated whether implicit learning of sequence by observation occurred in a serial reaction time task and whether the learning effects were modulated by model behavioral type. In Experiment 1, we let 20 participants perform a sequence for 12 blocks and chose the best and worst performance models based on reaction time and errors. In Experiment 2, new observers viewed a movie clip chosen from the following three: the best model performing the sequential task in the first (the first six blocks) or second session (the last six blocks), or the worst model performing the task in the first session. Then, the observers performed the observed sequence, a test sequence and awareness test. We found that (1) implicit sequential learning occurred by observation regardless of model behavior type, (2) the learning effects were not susceptible to model behavior type and (3) speed index reflecting reaction time became larger even in the test session when the observers viewed the best model performing the second session. Overall, observers developed general motor representations through action–observation. In addition, their responses were also contagious; if the model performed the sequence faster, the observer might be able to perform the sequence faster.

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Cholinergic systems are essential for late-stage maturation and refinement of motor cortical circuits

Journal of Neurophysiology ◽

10.1152/jn.00408.2014 ◽

2015 ◽

Vol 113 (5) ◽

pp. 1585-1597 ◽

Cited By ~ 7

Author(s):

Dhakshin S. Ramanathan ◽

James M. Conner ◽

Arjun A. Anilkumar ◽

Mark H. Tuszynski

Keyword(s):

Late Onset ◽

Adult Size ◽

Cortical Circuits ◽

Motor Tasks ◽

Cholinergic Lesions ◽

Cortical Motor ◽

Cholinergic Systems ◽

Temporal Course ◽

Motor Cortical ◽

Motor Representations

Previous studies reported that early postnatal cholinergic lesions severely perturb early cortical development, impairing neuronal cortical migration and the formation of cortical dendrites and synapses. These severe effects of early postnatal cholinergic lesions preclude our ability to understand the contribution of cholinergic systems to the later-stage maturation of topographic cortical representations. To study cholinergic mechanisms contributing to the later maturation of motor cortical circuits, we first characterized the temporal course of cortical motor map development and maturation in rats. In this study, we focused our attention on the maturation of cortical motor representations after postnatal day 25 (PND 25), a time after neuronal migration has been accomplished and cortical volume has reached adult size. We found significant maturation of cortical motor representations after this time, including both an expansion of forelimb representations in motor cortex and a shift from proximal to distal forelimb representations to an extent unexplainable by simple volume enlargement of the neocortex. Specific cholinergic lesions placed at PND 24 impaired enlargement of distal forelimb representations in particular and markedly reduced the ability to learn skilled motor tasks as adults. These results identify a novel and essential role for cholinergic systems in the late refinement and maturation of cortical circuits. Dysfunctions in this system may constitute a mechanism of late-onset neurodevelopmental disorders such as Rett syndrome and schizophrenia.

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Why is the Duration of Imagined Walking Underproduced? A dual-representation view on the mental imagery of locomotion

10.31234/osf.io/rm298 ◽

2018 ◽

Author(s):

Naohide Yamamoto ◽

Dagmara E. Mach ◽

John W. Philbeck ◽

Jennifer Van Pelt

Keyword(s):

Mental Imagery ◽

Temporal Structure ◽

Explicit Representation ◽

Production Task ◽

Dual Representation ◽

Implicit Representation ◽

Time Production ◽

Spatial Tasks ◽

Motor Representations ◽

Implicit Representations

Generally, imagining an action and physically executing it are thought to be controlled by common motor representations. However, imagined walking to a previewed target tends to be terminated more quickly than real walking to the same target, raising a question as to what representations underlie the two modes of walking. To address this question, the present study put forward a hypothesis that both explicit and implicit representations of gait are involved in imagined walking, and further proposed that the underproduction of imagined walking duration largely stems from the explicit representation due to its susceptibility to a general undershooting tendency in time production (i.e., the error of anticipation). Properties of the explicit and implicit representations were examined by manipulating their relative dominance during imagined walking through concurrent bodily motions, and also by using non-spatial tasks that extracted the temporal structure of imagined walking. Results showed that the duration of imagined walking subserved by the implicit representation was equal to that of real walking, and a time production task exhibited an equivalent underproduction bias as in imagined walking tasks that were based on the explicit representation. These findings are interpreted as evidence for the dual-representation view of imagined walking.

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Learning to control an articulatory synthesizer by imitating real speech

ZAS Papers in Linguistics ◽

10.21248/zaspil.40.2005.258 ◽

2005 ◽

Vol 40 ◽

pp. 63-78

Author(s):

Ian S. Howard ◽

Mark A. Huckvale

Keyword(s):

Vocal Tract ◽

Control Level ◽

Speech Development ◽

Inverse Model ◽

Control Parameters ◽

Speech Acquisition ◽

Phonological Structure ◽

Random Manner ◽

Motor Representations ◽

Initial Results

The goal of our current project is to build a system that can learn to imitate a version of a spoken utterance using an articulatory speech synthesiser. The approach is informed and inspired by knowledge of early infant speech development. Thus we expect our system to reproduce and exploit the utility of infant behaviours such as listening, vocal play, babbling and word imitation. We expect our system to develop a relationship between the sound-making capabilities of its vocal tract and the phonetic/phonological structure of imitated utterances. At the heart of our approach is the learning of an inverse model that relates acoustic and motor representations of speech. The acoustic to auditory mappings uses an auditory filter bank and a self-organizing phase of learning. The inverse model from auditory to vocal tract control parameters is estimated using a babbling phase, in which the vocal tract is essentially driven in a random manner, much like the babbling phase of speech acquisition in infants. The complete system can be used to imitate simple utterances through a direct mapping from sound to control parameters. Our initial results show that this procedure works well for sounds generated by its own voice. Further work is needed to build a phonological control level and achieve better performance with real speech.

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