scholarly journals Diverse operant control of different motor cortex populations during learning

2021 ◽  
Author(s):  
Nuria Vendrell-Llopis ◽  
Ching Fang ◽  
Albert J Qu ◽  
Rui M Costa ◽  
Jose M Carmena
Keyword(s):  
Motor Cortex ◽  
Calcium Imaging ◽  
Functional Organization ◽  
Pyramidal Tract ◽  
Neuron Activity ◽  
Machine Interface ◽  
Local Circuitry ◽  
To Receive ◽  
The Brain ◽  
Better Than

During motor learning, as well as during neuroprosthetic learning, animals learn to control motor cortex activity in order to generate behavior. Two different population of motor cortex neurons, intra-telencephalic (IT) and pyramidal tract (PT) neurons, convey the resulting cortical signals within and outside the telencephalon. Although a large amount of evidence demonstrates contrasting functional organization among both populations, it is unclear whether the brain can equally learn to control the activity of either class of motor cortex neurons. To answer this question, we used a Calcium imaging based brain-machine interface (CaBMI) and trained different groups of mice to modulate the activity of either IT or PT neurons in order to receive a reward. We found that animals learn to control PT neuron activity faster and better than IT neuron activity. Moreover, our findings show that the advantage of PT neurons is the result of characteristics inherent to this population as well as their local circuitry and cortical depth location. Taken together, our results suggest that motor cortex is optimized to control the activity of pyramidal track neurons, embedded deep in cortex, and relaying motor commands outside of the telencephalon.

scholarly journals Cellular precision of orientation and spatial frequency maps in macaque V1

2019 ◽  
Author(s):  
Nian-Sheng Ju ◽  
Shu-Chen Guan ◽  
Shi-Ming Tang ◽  
Cong Yu
Keyword(s):  
Spatial Frequency ◽  
Calcium Imaging ◽  
Functional Organization ◽  
Neuronal Response ◽  
Guiding Principle ◽  
Two Photon ◽  
Frequency Branch ◽  
Geometric Relationship ◽  
The Brain ◽  
Specific Orientation

AbstractFunctional organization of neuronal response properties along the surface of the neocortex is a fundamental guiding principle of neural computation in the brain. Despite this importance, the cellular precision of functional maps is still largely unknown. We address the challenge by using two-photon calcium imaging to measure cell-specific orientation and spatial frequency (SF) responses across fields of macaque V1 superficial layers. The cellular orientation maps confirm iso-orientation domains, but rarely show pinwheels. Pinwheels obtained through conventional Gaussian smoothing and vector summation of orientation responses mostly overlap with blood vessel regions, suggesting false singularities. Cellular SF maps clarify existing controversies by showing weak iso-frequency clusters, which also suggests a weak geometric relationship between orientation and SF maps. Most neurons are tuned to medium frequencies, but the tuning functions are often asymmetric with a wider low- or high-frequency branch, which may help encode low or high SF information for later decoding.

A quantitative study of neuronal discharge in areas 5, 2, and 4 of the monkey during fast arm movements

1991 ◽  
Vol 66 (2) ◽  
pp. 429-443 ◽  
Author(s):  
P. Burbaud ◽  
C. Doegle ◽  
C. Gross ◽  
B. Bioulac
Keyword(s):  
Motor Cortex ◽  
Somatosensory Cortex ◽  
Functional Organization ◽  
Receptive Fields ◽  
Arm Movements ◽  
Burst Duration ◽  
Movement Direction ◽  
Neuron Activity ◽  
Movement Onset ◽  
Area 5

1. The properties of parietal neurons were studied in four adult rhesus monkeys during fast arm movements. The animals were trained to perform flexion or extension of the forearm about the elbow in response to specific auditory cues. Single neuron activity was recorded in 272 area 5 neurons, 81 neurons of the somatosensory cortex, and 92 neurons of the motor cortex. 2. In area 5, 42% of neuronal changes occurred before movement onset (early changes) and 58% after (late changes), with 21% before the earliest electromyogram. The range of modification in activity took place between 260 ms before movement onset and 180 ms after. Complex receptive fields were found in area 5 with a greater proportion among the late neurons (72%) than among the early neurons (32%). 3. Different patterns of activity were observed in neurons recorded in both movement directions. Reciprocal neurons represented 52% of the motor cortex neurons and 41% of the neurons in the somatosensory cortex but only 14% of the area 5 neurons. Of the remainder area 5 neurons, 46% were direction-sensitive neurons and 39% coactivated neurons. This suggests a more complex encoding of movement direction in area 5 than in area 2 or 4. 4. Temporal characteristics of the neuronal bursts were quantitatively analyzed in areas 5, 2, and 4. Neuronal burst duration was longer in area 5 than in the other areas. Above all, a variability of burst parameters, which did not depend on variable movement execution, was noticed in area 5. Therefore neuronal activity in this cortical area cannot be simply explained by a convergence of sensory and motor inputs but may depend on the behavioral context in which the movement is performed. 5. A correlation between neuronal burst duration and movement duration was found in 41% of area 2 neurons. In area 5, this correlation was observed in 20% of the late neurons and in 14% of the early neurons. A correlation between neuronal discharge frequency and movement velocity was found in 34% of area 2 neurons and 24% of area 4 neurons. About 16% of both late and early neurons in area 5 showed such a correlation. These neurons received polyarticular input, and it is suggested that they may be involved in the kinematic encoding of polyarticular movements. 6. A topographic and functional organization of area 5 was noticed. In anterior area, 5, 83% of the neurons had receptive fields and most of the reciprocal neurons and those exhibiting a correlation with movement parameters were found there.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals XXIX.—Degenerations following Experimental Lesions in the Motor Cortex of the Monkey

1907 ◽  
Vol 27 ◽  
pp. 281-301 ◽  
Author(s):  
Sutherland Simpson ◽  
W. A. Jolly
Keyword(s):  
Spinal Cord ◽  
Motor Cortex ◽  
Pyramidal Tract ◽  
Brain And Spinal Cord ◽  
The Brain ◽  
Different Levels

The object of the present research was to follow, by the degeneration method, the course of the fibres proceeding from definite and limited areas of the motor cortex, and to determine to what extent there is a grouping or localisation of the fibres of the pyramidal tract at different levels in the brain and spinal cord.

scholarly journals Large-scale all-optical dissection of motor cortex connectivity reveals a segregated functional organization of mouse forelimb representations

2021 ◽  
Author(s):  
Francesco Resta ◽  
Elena Montagni ◽  
Giuseppe de Vito ◽  
Alessandro Scaglione ◽  
Anna Letizia Allegra Mascaro ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Large Scale ◽  
Functional Organization ◽  
Voluntary Movements ◽  
Motor Representation ◽  
Activation Patterns ◽  
Optogenetic Stimulation ◽  
All Optical ◽  
The Brain ◽  
Stimulation Of

In rodent motor cortex, the rostral forelimb area (RFA) and the caudal forelimb area (CFA) are major actors in orchestrating the control of forelimb complex movements. However, their intrinsic connections and reciprocal functional organization are still unclear, limiting our understanding of how the brain coordinates and executes voluntary movements. Here we causally probed cortical connectivity and activation patterns triggered by transcranial optogenetic stimulation of ethologically relevant complex movements exploiting a novel large-scale all-optical method in awake mice. Results show specific activation features for each movement class, providing evidence for a segregated functional organization of CFA and RFA. Importantly, we identified a second discrete lateral grasping representation area, namely lateral forelimb area (LFA), with unique connectivity and activation patterns. Therefore, we propose the LFA as a distinct motor representation in the forelimb somatotopic motor map.

Skill Representation in the Primary Motor Cortex After Long-Term Practice

2007 ◽  
Vol 97 (2) ◽  
pp. 1819-1832 ◽  
Author(s):  
Yoshiya Matsuzaka ◽  
Nathalie Picard ◽  
Peter L. Strick
Keyword(s):  
Motor Cortex ◽  
Motor Skills ◽  
Primary Motor Cortex ◽  
Functional Organization ◽  
Response Times ◽  
Internal Representation ◽  
Neuron Activity ◽  
Movement Sequences ◽  
A Site

The acquisition of motor skills can lead to profound changes in the functional organization of the primary motor cortex (M1). For example, performance of movement sequences after prolonged practice is associated with an expansion of the effector representation in M1. Paradoxically, there is little evidence that the activity of M1 neurons reflects acquired skills, especially sequences of movements. We examined the activity of M1 neurons during skilled movement sequences in macaques trained to successively hit targets on a monitor. The targets appeared either pseudorandomly (Random mode) or in one of two repeating sequences (Repeating mode). With practice, response times for repeating sequences substantially declined and the monkeys performed the task predictively. Highly trained animals retained the acquired skill after long gaps in practice. After >2 yr of training, 40% of M1 neurons were differentially active during the two task modes. Variations in movement kinematics did not fully explain the task-dependent modulation of neuron activity. Differentially active neurons were more strongly influenced by task mode than by kinematics. Our results suggest that practice sculpts the response properties of M1 neurons. M1 may be a site of storage for the internal representation of skilled sequential movements.

scholarly journals Local Application of Dopamine Inhibits Pyramidal Tract Neuron Activity in the Rodent Motor Cortex

2002 ◽  
Vol 88 (6) ◽  
pp. 3439-3451 ◽  
Author(s):  
Patrick W. Awenowicz ◽  
Linda L. Porter
Keyword(s):  
Motor Cortex ◽  
Dopamine Receptors ◽  
Spontaneous Activity ◽  
Cortical Neurons ◽  
Pyramidal Tract ◽  
D2 Receptor ◽  
Simultaneous Recording ◽  
Neuron Activity ◽  
Receptor Subtypes ◽  
Baseline Levels

Cortical neurons respond in a variety of ways to locally applied dopamine, perhaps because of the activation of different receptors within or among subpopulations of cells. This study was conducted to assess the effects of dopamine and the receptor subtypes that mediate the responses of a specific population of neurons, the pyramidal tract neurons (PTNs) in the rodent motor cortex. The specific subfamilies of dopamine receptors expressed by PTNs also were determined. PTNs were identified by antidromic stimulation in intact animals. Extracellular recordings of their spontaneous activity and glutamate-induced excitation were performed with multi-barrel pipettes to allow simultaneous recording and iontophoresis of several drugs. Prolonged (30 s) application of dopamine caused a progressive, nonlinear decrease in spontaneous firing rates for nearly all PTNs, with significant reductions from baseline spontaneous activity (71% of baseline levels) occurring between 20 and 30 s of iontophoresis. The D1 selective (SCH23390) and the D2 selective (eticlopride) antagonists were both effective in blocking dopamine-induced inhibition in nearly all PTNs. Mean firing levels were maintained within 3% of baseline levels during co-application of the D1 antagonist with dopamine and within 11% of baseline levels during co-application of the D2 antagonist and dopamine. SCH23390 was ineffective however, in 2 of 16 PTNs, and eticlopride was ineffective in 3 PTNs. The dopamine blockade by both antagonists in most neurons, along with the selective blockade by one, but not the other antagonist in a few neurons indicate that the overall population of PTNs exhibits a heterogeneous expression of dopamine receptors. The firing rate of PTNs was significantly enhanced by iontophoresis of glutamate (mean = 141% of baseline levels). These increases were attenuated significantly (mean= 98% of baseline) by co-application with dopamine in all PTNs, indicating dopaminergic interactions with glutamate transmission. The expression of dopamine receptors was studied with dual-labeling techniques. PTNs were identified by retrograde labeling with fast blue and the D1a, D2, or D5 receptor proteins were stained immunohistochemically. Some, but not all PTNs, showed labeling for D1a, D2, or D5 receptors. The D1a and D2 receptor immunoreactivity was observed primarily in the somata of PTNs, whereas D5 immunoreactivity extended well into the apical dendrites of PTNs. In accordance with findings of D1 and D2 receptor antagonism of dopamine's actions, the identification of three DA receptor subtypes on PTNs suggests that dopamine can directly modulate PTN activity through one or more receptor subtypes.

scholarly journals Robust single neuron tracking of calcium imaging in behaving Hydra

2020 ◽  
Author(s):  
Thibault Lagache ◽  
Alison Hanson ◽  
Adrienne Fairhall ◽  
Rafael Yuste
Keyword(s):  
Calcium Imaging ◽  
Single Neuron ◽  
Functional Organization ◽  
Ground Truth ◽  
Time Lapse ◽  
Automatic Monitoring ◽  
Local Deformation ◽  
Neuron Activity ◽  
Imaging Data ◽  
Statistical Characterization

AbstractMeasuring the activity of neuronal populations with calcium imaging can capture emergent functional properties of neuronal circuits with single cell resolution. However, the motion of freely behaving animals, together with the intermittent detectability of calcium sensors, can hinder automatic long-term monitoring of the activity of individual neurons and the subsequent statistical characterization of neuronal functional organization. We report the development and open-source implementation of a multi-step cellular tracking algorithm (Elastic Motion Correction and Concatenation or EMC2) that compensates for the intermittent disappearance of moving neurons by integrating local deformation information from detectable neurons. We demonstrate the accuracy and versatility of our algorithm using calcium imaging data from behaving Hydra, which experiences major body deformation during its contractions. We quantify the performance of our algorithm using ground truth manual tracking of neurons, along with synthetic time-lapse sequences, covering a large range of particle motions and detectability parameters. Combining automatic monitoring of single neuron activity over long time-lapse sequences in behaving animals with statistical clustering, we characterize and map neuronal ensembles in behaving Hydra. We document the existence three major non-overlapping ensembles of neurons (CB, RP1 and RP2) whose activity correlates with contractions and elongations. Our results prove that the EMC2 algorithm can be used as a robust platform for neuronal tracking in behaving animals.

The pathways for action

2017 ◽  
Author(s):  
Ray Guillery
Keyword(s):  
Motor Cortex ◽  
Pyramidal Tract ◽  
Specific Area ◽  
Body Parts ◽  
Topographic Map ◽  
Early Nineteenth Century ◽  
Motor Pathway ◽  
The Standard Model ◽  
The Brain ◽  
Anatomical Evidence

Early nineteenth-century studies demonstrated, on the basis of clinical, experimental, and anatomical evidence, that a motor pathway, the corticospinal or pyramidal tract, passes from a specific area of the cortex, the precentral motor cortex, to the brainstem and spinal cord. The motor cortex can be seen as a topographic map of the movable body parts, and damage to the cortex or pathways produces correspondingly localized paralysis. However, there are a great many other pathways that link other areas of the cortex to parts of the brain active in the control of movements. These still play a puzzling role in the standard model where the control of movements focuses on cortical contributions to voluntary movements by the corticospinal pathways.

scholarly journals Operant conditioning of motor cortex neurons reveals neuron-subtype-specific responses in a brain-machine interface task

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Martha Gabriela Garcia-Garcia ◽  
Cesar Marquez-Chin ◽  
Milos R. Popovic
Keyword(s):  
Operant Conditioning ◽  
Cortical Neurons ◽  
Degrees Of Freedom ◽  
Neuron Activity ◽  
Output Stage ◽  
Intrinsic Factors ◽  
Bursting Neurons ◽  
Machine Interface ◽  
Improved Performance ◽  
The Brain

AbstractOperant conditioning is implemented in brain-machine interfaces (BMI) to induce rapid volitional modulation of single neuron activity to control arbitrary mappings with an external actuator. However, intrinsic factors of the volitional controller (i.e. the brain) or the output stage (i.e. individual neurons) might hinder performance of BMIs with more complex mappings between hundreds of neurons and actuators with multiple degrees of freedom. Improved performance might be achieved by studying these intrinsic factors in the context of BMI control. In this study, we investigated how neuron subtypes respond and adapt to a given BMI task. We conditioned single cortical neurons in a BMI task. Recorded neurons were classified into bursting and non-bursting subtypes based on their spike-train autocorrelation. Both neuron subtypes had similar improvement in performance and change in average firing rate. However, in bursting neurons, the activity leading up to a reward increased progressively throughout conditioning, while the response of non-bursting neurons did not change during conditioning. These results highlight the need to characterize neuron-subtype-specific responses in a variety of tasks, which might ultimately inform the design and implementation of BMIs.

scholarly journals EEG Measurement as a Tool for Rehabilitation Assessment and Treatment

2020 ◽  
Author(s):  
Hideki Nakano
Keyword(s):  
Motor Cortex ◽  
Muscle Activity ◽  
Brain Activity ◽  
Measurement Techniques ◽  
Assessment And Treatment ◽  
Simple Measurement ◽  
Machine Interface ◽  
The Brain ◽  
Rehabilitation Assessment

In recent years, neuroscience-based rehabilitation, also known as neurorehabilitation, has been attracting increasing attention worldwide. Electroencephalography (EEG) has been widely used in clinical practice as a tool for the evaluation and treatment of rehabilitation because of its noninvasive and simple measurement of human brain activity. EEG-electromyography coherence is a method to analyze the synchronization between the motor cortex and muscle activity during movement and to quantitatively assess how the motor cortex controls muscle activity. In addition, recent advances in analysis and measurement techniques have made it possible to estimate the source of EEG signals, thus serving as a method to evaluate rehabilitation. The brain-machine interface, which integrates medicine and engineering, has been widely applied in the treatment of rehabilitation and for improving the quality of life. This chapter provides an overview of EEG, and its uses as a tool for rehabilitation assessment and treatment.

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