The neural bases of the reach–grasp movement in humans: Quantitative evidence from brain lesions

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(10)

Published: March 5, 2025

Visually guided grasping is a fundamental building block of animal behavior, the specific neural mechanisms which remain poorly documented in human brain. We have mapped causal contribution different brain parts to behavior by studying kinematic parameters 33 patients with tumors, engaged actions directed toward objects sizes. Using motion capture techniques, we analyzed dynamics grip aperture and wrist transport. Voxel-based lesion-symptom mapping analysis was applied correlate lesion volumes behavioral deficits. Results showed that lesions anterior lateral bank intraparietal sulcus produced impaired finger scaling related object size. Conversely, velocity associated dorsal premotor cortex (PMd). Grip deficits following dominant hemisphere were bilateral unilateral when nondominant lesions. Impaired transport during reaching first segment superior longitudinal fasciculus. Our work highlights an architecture network humans, unique species-specific features. hypothesize model geometry for hand preshaping coded left then shared right hemisphere. Execution motor program performed PMd on corresponding side.

Language: Английский

Neural representation of action symbols in primate frontal cortex

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: March 4, 2025

Abstract At the core of intelligence is proficiency in solving new problems, including those that differ dramatically from problems seen before. Problem-solving, turn, depends on goal-directed generation novel thoughts and behaviors 1 , which has been proposed to rely internal representations discrete units, or symbols, processes can recombine them into a large set possible composite 1–11 . Although this view influential formulating cognitive-level explanations behavior, definitive evidence for neuronal substrate symbols remained elusive. Here, we identify neural population encoding action symbols—internal, recombinable units motor behavior—localized specific area frontal cortex. In macaque monkeys performing drawing-like task designed assess recombination learned sequences, found behavioral three critical features indicate actions have an underlying symbolic representation: (i) invariance over low-level parameters; (ii) categorical structure, reflecting classes action; (iii) sequences. simultaneous recordings across motor, premotor, prefrontal cortex, planning-related activity ventral premotor cortex encodes manner that, like reflects invariance, recombination, properties indicating representation. Activity no other recorded exhibited combination properties. These findings reveal representation localized PMv, therefore putative cognitive operations.

Language: Английский

What Else Is Happening to the Mirror Neurons?—A Bibliometric Analysis of Mirror Neuron Research Trends and Future Directions (1996–2024)

Brain and Behavior, Journal Year: 2025, Volume and Issue: 15(4)

Published: April 1, 2025

ABSTRACT Background Since its discovery in the late 20th century, research on mirror neurons has become a pivotal area neuroscience, linked to various cognitive and social functions. This bibliometric analysis explores trajectory, key topics, future trends field of neuron research. Methods We searched Web Science Core Collection (WoSCC) database for publications from 1996 2024 Statistical visualization analyses were performed using CiteSpace VOSviewer. Results Publication output peaked 2013 remained active. High‐impact journals such as Science, Brain, Neuron, PNAS , NeuroImage frequently feature findings system, including distribution, neural coding, roles intention understanding, affective empathy, motor learning, autism, neurological disorders. Keyword clustering reveals major directions neurostimulation, whereas burst detection underscores emerging significance brain‐computer interfaces (BCIs). Research methodologies have been evolving traditional electrophysiological recordings advanced techniques functional magnetic resonance imaging, transcranial stimulation, BCIs, highlighting dynamic, multidisciplinary progression. Conclusions study identifies areas associated with anticipates that work will integrate artificial intelligence, clinical interventions, novel neuroimaging techniques, providing new perspectives complex socio‐cognitive issues their applications both basic science practice.

Language: Английский