Supplementary motor area: neuronal response to motor instructions

1980 ◽  
Vol 43 (1) ◽  
pp. 60-68 ◽  
Author(s):  
J. Tanji ◽  
K. Taniguchi ◽  
T. Saga

1. Single-unit recordings were obtained from the supplementary motor area of the cerebral cortex of two monkeys during execution of learned movements 2. Monkeys were required to push or pull a cast attached to the right forelimb in response to a sudden perturbation delivered via the cast. An instruction as to the direction of the monkey's movement was delivered 2.5--5 s prior to the occurrence of the perturbation and correct performance, therefore, required the animal to develop a preparatory state prior to the perturbation. 3. Of many hundreds of neurons recorded, 201 exhibited instruction-induced changes of activity during the period intervening between the instruction and the perturbation-triggered movement. 4. In 94 neurons, effects of the instruction were differential depending on which of the two instructions was given, whereas in 107 neurons, effects were nondifferential. The latencies of the differential responses appeared to be shorter (starting as early as 140 ms after the instruction). 5. The magnitude of the instruction effects varied in parallel with development of enhanced motor skill as the monkeys gained more experience in responding to the triggering stimulus. 6. These observations substantiate the hypothesis that the supplementary motor area plays a part in modifying a sensory-triggered motor output.

2012 ◽  
Vol 117 (5) ◽  
pp. 844-850 ◽  
Author(s):  
Juan Martino ◽  
Enrique Marco de Lucas ◽  
Francisco Javier Ibáñez-Plágaro ◽  
José Manuel Valle-Folgueral ◽  
Alfonso Vázquez-Barquero

Foix-Chavany-Marie syndrome (FCMS) is a rare type of suprabulbar palsy characterized by an automaticvoluntary dissociation of the orofacial musculature. Here, the authors report an original case of FCMS that occurred intraoperatively while resecting the pars opercularis of the inferior frontal gyrus. This 25-year-old right-handed man with an incidentally diagnosed right frontotemporoinsular tumor underwent surgery using an asleep-awake-asleep technique with direct cortical and subcortical electrical stimulation and a transopercular approach to the insula. While resecting the anterior part of the pars opercularis the patient suffered sudden anarthria and bilateral facial weakness. He was unable to speak or show his teeth on command, but he was able to voluntarily move his upper and lower limbs. This syndrome lasted for 8 days. Postoperative diffusion tensor imaging tractography revealed that connections of the pars opercularis of the right inferior frontal gyrus with the frontal aslant tract (FAT) and arcuate fasciculus (AF) were damaged. This case supplies evidence for localizing the structural substrate of FCMS. It was possible, for the first time in the literature, to accurately correlate the occurrence of FCMS to the resection of connections between the FAT and AF, and the right pars opercularis of the inferior frontal gyrus. The FAT has been recently described, but it may be an important connection to mediate supplementary motor area control of orofacial movement. The present case also contributes to our knowledge of complication avoidance in operculoinsular surgery. A transopercular approach to insuloopercular gliomas can generate FCMS, especially in cases of previous contralateral lesions. The prognosis is favorable, but the patient should be informed of this particular hazard, and the surgeon should anticipate the surgical strategy in case the syndrome occurs intraoperatively in an awake patient.


2021 ◽  
Author(s):  
Timothy P. Morris ◽  
Aaron Kucyi ◽  
Sheeba Arnold Anteraper ◽  
Maiya Rachel Geddes ◽  
Alfonso Nieto-Castañon ◽  
...  

AbstractInformation about a person’s available energy resources is integrated in daily behavioral choices that weigh motor costs against expected rewards. It has been posited that humans have an innate attraction towards effort minimization and that executive control is required to overcome this prepotent disposition. With sedentary behaviors increasing at the cost of millions of dollars spent in health care and productivity losses due to physical inactivity-related deaths, understanding the predictors of sedentary behaviors will improve future intervention development and precision medicine approaches. In 64 healthy older adults participating in a 6-month aerobic exercise intervention, we use neuroimaging (resting state functional connectivity), baseline measures of executive function and accelerometer measures of time spent sedentary to predict future changes in objectively measured time spent sedentary in daily life. Using cross-validation and bootstrap resampling, our results demonstrate that functional connectivity between 1) the anterior cingulate cortex and the supplementary motor area and 2) the right anterior insula and the left temporoparietal/temporooccipital junction, predict changes in time spent sedentary, whereas baseline cognitive, behavioral and demographic measures do not. Previous research has shown activation in and between the anterior cingulate and supplementary motor area as well as in the right anterior insula during effort avoidance and tasks that integrate motor costs and reward benefits in effort-based decision making. Our results add important knowledge toward understanding mechanistic associations underlying complex sedentary behaviors.


2020 ◽  
pp. 1-5
Author(s):  
Jaime A. Quirarte ◽  
Vinodh A. Kumar ◽  
Ho-Ling Liu ◽  
Kyle R. Noll ◽  
Jeffrey S. Wefel ◽  
...  

Supplementary motor area (SMA) syndrome is well known; however, the mechanism underlying recovery from language SMA syndrome is unclear. Herein the authors report the case of a right-handed woman with speech aphasia following resection of an oligodendroglioma located in the anterior aspect of the left superior frontal gyrus. The patient exhibited language SMA syndrome, and functional MRI (fMRI) findings 12 days postoperatively demonstrated a complete shift of blood oxygen level–dependent (BOLD) activation to the contralateral right language SMA/pre-SMA as well as coequal activation and an increased volume of activation in the left Broca’s area and the right Broca’s homolog. The authors provide, to the best of their knowledge, the first description of dynamic changes in task-based hemispheric language BOLD fMRI activations across the preoperative, immediate postoperative, and more distant postoperative settings associated with the development and subsequent complete resolution of the clinical language SMA syndrome.


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