scholarly journals The destination defines the journey: an examination of the kinematics of hand-to-mouth movements

2016 ◽  
Vol 116 (5) ◽  
pp. 2105-2113 ◽  
Author(s):  
Jason W. Flindall ◽  
Claudia L. R. Gonzalez

Long-train electrical stimulation of the motor and premotor cortices of nonhuman primates can produce either hand-to-mouth or grasp-to-inspect movements, depending on the precise location of stimulation. Furthermore, single-neuron recording studies identify discrete neuronal populations in the inferior parietal and ventral premotor cortices that respond uniquely to either grasp-to-eat or grasp-to-place movements, despite their identical mechanistic requirements. These studies demonstrate that the macaque motor cortex is organized around producing functional, goal-oriented movements, rather than simply fulfilling muscular prerequisites of action. In humans, right-handed hand-to-mouth movements have a unique kinematic signature; smaller maximum grip apertures are produced when grasping to eat than when grasping to place identical targets. This is evidence that the motor cortex in humans is also organized around producing functional movements. However, in both macaques and humans, grasp-to-eat/hand-to-mouth movements have always been elicited using edible targets and have (necessarily) been paired with mouth movement. It is therefore unknown whether the kinematic distinction is a natural result of grasping food and/or is simply attributable to concurrent opening of the mouth while grasping. In experiment 1, we used goal-differentiated grasping tasks, directed toward edible and inedible targets, to show that the unique kinematic signature is present even with inedible targets. In experiment 2, we used the same goal-differentiated grasping tasks, either coupled with or divorced from an open-mouth movement, to show that the signature is not attributable merely to a planned opening of the mouth during the grasp. These results are discussed in relation to the role of hand-to-mouth movements in human development, independently of grasp-to-eat behavior.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Igor Lavrov ◽  
Timur Latypov ◽  
Elvira Mukhametova ◽  
Brian Lundstrom ◽  
Paola Sandroni ◽  
...  

AbstractElectrical stimulation of the cerebral cortex (ESCC) has been used to treat intractable neuropathic pain for nearly two decades, however, no standardized approach for this technique has been developed. In order to optimize targeting and validate the effect of ESCC before placing the permanent grid, we introduced initial assessment with trial stimulation, using a temporary grid of subdural electrodes. In this retrospective study we evaluate the role of electrode location on cerebral cortex in control of neuropathic pain and the role of trial stimulation in target-optimization for ESCC. Location of the temporary grid electrodes and location of permanent electrodes were evaluated in correlation with the long-term efficacy of ESCC. The results of this study demonstrate that the long-term effect of subdural pre-motor cortex stimulation is at least the same or higher compare to effect of subdural motor or combined pre-motor and motor cortex stimulation. These results also demonstrate that the initial trial stimulation helps to optimize permanent electrode positions in relation to the optimal functional target that is critical in cases when brain shift is expected. Proposed methodology and novel results open a new direction for development of neuromodulation techniques to control chronic neuropathic pain.


Author(s):  
Caroline Howlett ◽  
Brandon C. Wheeler

AbstractWhile the role of ecological factors in shaping primate social systems has been a central focus for decades, less attention has been given to phylogenetic relationships and the potential role of underlying proximate mechanisms. This study aimed to investigate the relationship between one such proximate mechanism, prenatal androgen effects (PAEs), and aspects of social behavior in female nonhuman primates using the 2D:4D ratio as a proxy for PAEs and phylogenetically controlled methods. In general, female 2D:4D ratios were highest in monogamous species (low inferred PAEs) and lowest in polygynandrous and polygynous species (high inferred PAEs). 2D:4D ratios also varied with the form of polygyny/polygynandry, potentially with regard to the need for competitive over cooperative behaviors and the intensity of female reproductive competition. Species characterized by female dominance had lower 2D:4D ratios than species characterized by male dominance or codominance. There were no significant relationships between 2D:4D ratio and either degree of frugivory or group size. Relationships between 2D:4D ratios and the directional consistency index and 2D:4D ratios and rates of female–female agonism were also nonsignificant although sample sizes for both of these variables were small. Female social relationships are a manifestation of complex competitive and cooperative behaviors and the results suggest that PAEs may act as a proximate mechanism underlying the expression of certain aspects of behavior in female primates in ways that are adaptive to their social system.


1992 ◽  
Vol 77 (2) ◽  
pp. 209-216 ◽  
Author(s):  
Michael M. Haglund ◽  
Mitchel S. Berger ◽  
Dennis D. Kunkel ◽  
JoAnn E. Franck ◽  
Saadi Ghatan ◽  
...  

✓ The role of specific neuronal populations in epileptic foci was studied by comparing epileptic and nonepileptic cortex removed from patients with low-grade gliomas. Epileptic and nearby (within 1 to 2 cm) nonepileptic temporal lobe neocortex was identified using electrocorticography. Cortical specimens taken from four patients identified as epileptic and nonepileptic were all void of tumor infiltration. Somatostatin- and γ-aminobutyric acid (GABAergic)-immunoreactive neurons were identified and counted. Although there was no significant difference in the overall cell count, the authors found a significant decrease in both somatostatin- and GABAergic-immunoreactive neurons (74% and 51 %, respectively) in the epileptic cortex compared to that in nonepileptic cortex from the same patient. It is suggested that these findings demonstrate changes in neuronal subpopulations that may account for the onset and propagation of epileptiform activity in patients with low-grade gliomas.


2020 ◽  
Vol 598 (4) ◽  
pp. 839-851 ◽  
Author(s):  
Giovanna Pilurzi ◽  
Francesca Ginatempo ◽  
Beniamina Mercante ◽  
Luigi Cattaneo ◽  
Giovanni Pavesi ◽  
...  

1988 ◽  
Vol 59 (3) ◽  
pp. 796-818 ◽  
Author(s):  
C. S. Huang ◽  
M. A. Sirisko ◽  
H. Hiraba ◽  
G. M. Murray ◽  
B. J. Sessle

1. The technique of intracortical microstimulation (ICMS), supplemented by single-neuron recording, was used to carry out an extensive mapping of the face primary motor cortex. The ICMS study involved a total of 969 microelectrode penetrations carried out in 10 unanesthetized monkeys (Macaca fascicularis). 2. Monitoring of ICMS-evoked movements and associated electromyographic (EMG) activity revealed a general pattern of motor cortical organization. This was characterized by a representation of the facial musculature, which partially enclosed and overlapped the rostral, medial, and caudal borders of the more laterally located cortical regions representing the jaw and tongue musculatures. Responses were evoked at ICMS thresholds as low as 1 microA, and the latency of the suprathreshold EMG responses ranged from 10 to 45 ms. 3. Although contralateral movements predominated, a representation of ipsilateral movements was found, which was much more extensive than previously reported and which was intermingled with the contralateral representations in the anterior face motor cortex. 4. In examining the fine organizational pattern of the representations, we found clear evidence for multiple representation of a particular muscle, thus supporting other investigations of the motor cortex, which indicate that multiple, yet discrete, efferent microzones represent an essential organizational principle of the motor cortex. 5. The close interrelationship of the representations of all three muscle groups, as well as the presence of a considerable ipsilateral representation, may allow for the necessary integration of unilateral or bilateral activities of the numerous face, jaw, and tongue muscles, which is a feature of many of the movement patterns in which these various muscles participate. 6. In six of these same animals, plus an additional two animals, single-neuron recordings were made in the motor and adjacent sensory cortices in the anesthetized state. These neurons were electrophysiologically identified as corticobulbar projection neurons or as nonprojection neurons responsive to superficial or deep orofacial afferent inputs. The rostral, medial, lateral, and caudal borders of the face motor cortex were delineated with greater definition by ICMS and these electrophysiological procedures than by cytoarchitectonic features alone. We noted that there was an approximate fit in area 4 between the extent of projection neurons and field potentials anti-dromically evoked from the brain stem and the extent of positive ICMS sites.(ABSTRACT TRUNCATED AT 400 WORDS)


Blood ◽  
1984 ◽  
Vol 64 (5) ◽  
pp. 1074-1078
Author(s):  
JM Pesando ◽  
TA Conrad

Serologic studies using four murine monoclonal antibodies specific for the common acute lymphoblastic leukemia antigen (CALLA) and five monoclonal antibodies specific for the gp24 surface antigen indicate that these leukemia-associated antigens are present on cells of comparable tissues in man and in four nonhuman primates. As in man, adherent cell populations obtained from skin, lung, and bone marrow of Macaca fascicularis, M mulatta, M nemestrina, and Papio cynocephalus react with these antibodies. Similarly, granulocytes from both man and these nonhuman primates bind CALLA- and gp24-specific antibodies. Radioimmune precipitation experiments confirm the identity of these antigens. Our studies suggest that nonhuman primates can be used to screen serologic reagents to leukemia-associated antigens for potential toxic effects on normal tissues prior to their use in man. Similarly, nonhuman primates could be employed to assess the possible role of antigen-positive stromal cells in the reconstitution of bone marrow following transplantation.


2021 ◽  
Vol 5 (S2) ◽  
pp. 96-107
Author(s):  
Leonid Griffen ◽  
Nadiia Ryzheva ◽  
Dmytro Nefodov ◽  
Lyudmila Hryashchevskaya

Current tendencies question the role of science in modern society, force returning to the processes of formation of the scientific paradigm. The latter was complex and nonlinear, and the formation of scientific principles of cognition was their natural result. Throughout human history, the knowledge about the objective world has been acquired and used in various, historically necessary forms – both in the methodology of cognition and in the method of systematisation, which was determined by the level of their accumulation. The accumulation of knowledge took place in different ways: in the process of direct practical activity, on the basis of supposedly “foreign” contemplation and as a result of conscious influence on an object of study (experiment) with their different “specific weight” at different historical stages. As for the systematisation, the need for which was determined by systemic nature of an object of knowledge and the social nature of knowledge, throughout the history of mankind its forms differed considerably, but, in the end, were reduced to three main ones. 


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