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At least 19 recordsLinked to original sources

PubMed1989

Neuromagnetic fields accompanying unilateral finger movements: pre-movement and movement-evoked fields.

Neuromagnetic fields accompanying voluntary flexions of the right index finger were studied in five subjects. In all subjects, slow magnetic fields were observed over the central scalp beginning about 1 second prior to movement onset. These fields displayed a similar time course to the electrically recorded "readiness potential", but with reversals of field direction over regions of the rolandic fissure over both hemispheres. Least-squares fitting of two current dipole sources for the pre-movement fields resulted in a consistent localization of one source in the region of the rolandic fissure contralateral to the side of movement in four subjects. Ipsilateral dipole sources fitted inconsistently at deeper locations or outside the head indicating the inability of a single dipole source to account for the ipsilateral fields. A large field reversal was also observed over the contralateral (left) hemisphere, 90-130 ms after onset of EMG activity in the active muscles. In some subjects, single dipole sources could be fitted to this "movement-evoked" field at locations slightly deeper and posterior to the pre-movement source locations in the contralateral hemisphere, possibly indicating unilateral activation of somatosensory cortex related to sensory feedback during the onset of this movement. Subtraction of pre-movement field activity from post-movement fields improved the ability to fit a single contralateral rolandic source for all subjects suggesting that pre-movement sources continue to be active during movement onset. These findings confirm previous reports that voluntary finger movements are preceded by slow magnetic fields.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Primate motor cortex and free arm movements to visual targets in three-dimensional space. III. Positional gradients and population coding of movement direction from various movement origins.

In one experiment, we studied the relations between the frequency of discharge of 274 single cells in the arm area of the motor cortex of the monkey and the actively maintained position of the hand in space. We found that the frequency of discharge of 63.9% of the cells studied was a multilinear function of the position of the hand in space according to the following equation (multiple linear regression): d = f + fxsx + fysy + fzsz, where d is the discharge rate of a single cell, f, fx, fy, fz are regression coefficients, and sx, sy, sz are the coordinates of the position of the hand. The equation above defines a positional gradient which implies that the frequency of cell discharge will increase at a maximum rate when the position of the hand changes along a certain direction; we call this direction of orientation of the positional gradient, and the rate of change in discharge rate along this orientation, the magnitude of the gradient. The orientations of the positional gradients were distributed throughout three-dimensional (3-D) space and their magnitudes differed among different cells. In a different experiment, we studied the changes in activity of 289 cells in the arm area of the motor cortex when the monkeys made equal-amplitude movements that started from different points in space, were in the same direction, and traveled along parallel trajectories in 3-D space. Four pairs of such movement directions (i.e., a total of 8 movement directions) were studied for every cell, and the changes in cell activity associated with movements within each pair were compared. We found that these changes in cell activity did not differ statistically for 68.4% of the movement pairs studied but did differ for the remaining 31.6%. The data from the whole population of cells studied in this experiment were analyzed using the population vector analysis described in the preceding paper (Georgopoulos et al., 1988). Thus, 8 population vectors were calculated, 1 for each of the 8 movement directions studied. We found that the direction of the population vector was close to the direction of the corresponding movement. These results indicate that the population vector provides unique information concerning the direction of the movement even when the point of origin of the movement varies in 3-D space.

Animals↗

PubMed1992

Movement features and H-reflex modulation. II. Passive rotation, movement velocity and single leg movement.

Modulation of soleus H-reflex magnitudes during pedalling, and their approximation when seated with appropriate joint positions and contractile activity was demonstrated in the previous paper. The present study investigated the modulation of H-reflexes during (A) pedalling movement in the absence of contractile activity, (B) different movement velocities and (C) movement of a single limb. Using a customized tandem cycle ergometer, seated subjects with trunk supported relaxed their leg muscles and allowed their legs to be rotated. Their feet were supported on the pedals with the ankle braced. Reflexes were collected at four phases in the movement cycle (with some at 13 phases) and with speeds of 5-60 revolutions per min (cycle times from 12 to 1 s). The results showed that (i) reflex magnitude substantially decreased with limb rotation (P less than 0.05). The degree of inhibition was dependent on the phase position. (ii) Increasing speed of passive rotation increased the inhibition at all positions, but was most pronounced near the fullest flexion of hip and knee. When subjects actively pedalled, the relationship between speed and inhibition remained. (iii) When the contralateral leg was moved and the target leg was stationary, crossed projection of reflex inhibition was clear. (iv) The reflex gain measured during active pedalling of one leg was similar to that observed during two legged pedalling. Again, a crossed effect from the contralateral leg could be observed. We conclude that the net influence of discharge from movement-elicited afference is inhibitory on this reflex path and that the reflex modulation during pedalling arises from overlaid sources.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

[Study on grinding movements in chewing. 2. Relationship between grinding movement in chewing-like empty jaw movement and occlusal form of molar].

The purpose of this study is to clarify the relationship between the occlusal form of a molar and mandibular movement. For this purpose I measured the occlusal form of the upper first molar, and the 3-dimensional movement of the lower first molar during the grinding movement in chewing-similar to empty jaw movement. In this study the following three parameters were analyzed.; (1) the distance between the upper and lower first molars in the lateral occlusal position, (2) the inclination of the cusp-slope, (3) the inclination of the lower first molar path. Results were follows: 1) On the working side, the inclination of the cusp-slope is closely connected to that of the path, 2) On the non-working side, the correlation between the inclination of the cusp-slope, and that of the path was so weak, as to be statistically insignificant. 3) The distance between the molars tended to increase as the inclination of the path steepened. This tendency was marked on the non-working side. The results mentioned above proved that, in cases with steeper anterior guidance, the upper and lower first molars disclude more on both the working and non-working sides. On the working side, however, the steeper cusp-slope prevents excessive disclusion of molars.

Dental Occlusion↗

PubMed1989

[Study on grinding movements in chewing. 1. A comparison between grinding movement in chewing-like empty jaw movement and lateral excursion].

The purpose of this study is to clarify the relationship between grinding movements during chewing, and lateral excursions starting from the intercuspal position. For this purpose, I measured two different types of three-dimensional mandibular movement; lateral excursions and empty-jaw movement like chewing in 10 subjects, and compared these paths with each other in the lateral occlusal position, when the incisal point is 2.0 mm distant from the intercuspal position. The results can be summarized as follows: 1. The two positions of the incisal point were statistically coincident. 2. The position of both working and non-working side molars during chewing tended to be inferior to that during lateral excursion. 3. The moved distance of the working side condyle during chewing was significantly less than that during lateral excursion. 4. The position of the non-working side condyle during chewing tended to be medial to that during lateral excursion. 5. The difference in the condylar position was deeply related to that in the molar position. The differences mentioned above were considered to be originated from the difference in the masticatory muscle activity and the occlusal contact.

Dental Occlusion, Centric↗

PubMed1992

Role of primate basal ganglia and frontal cortex in the internal generation of movements. II. Movement-related activity in the anterior striatum.

In order to more comprehensively assess the role of the basal ganglia in the internal generation of movements, we studied the activity of neurons in the head of the caudate and in the rostral putamen in relation to the execution of movements. Monkeys performed self-initiated and stimulus-triggered arm reaching movements in separate blocks of trials. With stimulus-triggered movements, 217 striatal neurons increased their activity after the trigger stimulus (127 in caudate, 90 in putamen). Of these, 68 neurons showed time-locked responses to the trigger stimulus, with a median latency of 60 ms, that were independent of visual or auditory stimulus modalities. Three quarters of responses were conditional on a movement being performed. These responses may participate in neuronal processes through which the reception of a stimulus is translated into the execution of a behavioral reaction. Further, 44 neurons increased their activity before the earliest muscle activity without being clearly time-locked to the stimulus (148-324 ms before movement onset), 55 neurons were activated later before the movement, and 50 neurons were activated after movement onset. With self-initiated movements, 106 striatal neurons showed movement-related activity beginning up to 460 ms before movement onset (52 in caudate, 54 in putamen). Comparisons between the two types of movement were made on 53 neurons with premovement activity beginning more than 500 ms before self-initiated movements. Only one fifth of them also showed movement-related activity with stimulus-triggered movements, including trigger responses. Comparisons among 39 neurons with movement-related activity during self-initiated arm movements showed that about half of them also showed movement-related activity with stimulus-triggered movements. These data demonstrate a considerably segregated population of striatal neurons engaged in the internal generation of movements, whereas processes underlying the execution of movements appear to involve overlapping neuronal populations.

Animals↗

PubMed1992

Influences of hand movements on eye movements in tracking tasks in man.

We investigated horizontal smooth pursuit eye movements and hand movements in tracking tasks in order to find out whether hand movements influence eye movements and if so, in what ways. Externally controlled target movements were tracked either by the eyes alone or by the eyes and right hand together. Because a possible influence might depend on the stimulus, we used two classes of target movements: sinusoidal target movements (predictable target movements) and pseudo-random target movements (unpredictable target movements). Our data show that the eye movements contained only a few small saccades when sinusoidal target movements with frequencies higher than about 1 Hz were tracked by eyes and hand together. More and larger saccades were made when the same target movements were tracked by the eyes alone. The difference in smoothness of eye movements was highly significant between the two tracking conditions. Such a difference was not found during the tracking of a pseudo-random target motion. This suggests that the influence of hand movements is related to the predictability of the stimulus. In contrast to the gain of the smooth pursuit eye movements and the maximum of the cross-correlation function, the gain of the composite eye movements did not depend on the tracking condition. The delay of the eye movements with respect to the (sinusoidal) target movements also showed no dependence on the tracking condition. Visual feedback from the tracking hand was found not to play a role in the difference in eye movements for the two tracking conditions.

Feedback↗

PubMed1989

Distribution of neurons with set- and movement-related activity before hand and foot movements in the premotor cortex of rhesus monkeys.

Neuronal activity was studied in the premotor cortex (PM) of two rhesus monkeys, each of which performed both forelimb and hindlimb movements. On each trial, the monkey received a visual instruction stimulus (IS) that indicated whether a foot or a hand movement would be rewarded on that trial. After a delay period, during which the monkey withheld an overt movement, a visual trigger stimulus (TS) was presented to indicate that the monkey should execute a movement. Of 572 task-related neurons recorded in PM, 149 neurons showed set-related activity, defined as a significant increase or decrease in discharge rate throughout most of the instructed delay period, and 299 neurons showed movement-related activity, defined as a significant change in discharge rate between the TS and movement onset. Both set- and movement-related activity were subdivided into three patterns: activity modulation 1) before a foot movement only ("foot" neurons); 2) before a hand movement only ("hand" neurons); and 3) before both foot and hand movements ("mixed" neurons). The distribution of set-related neurons mostly overlapped with that of movement-related neurons, although set-related neurons were located in more restricted regions than movement-related neurons. "Foot" neurons with set- and movement-related activity were distributed near the superior precentral sulcus. "Hand" neurons were mainly located lateral to the "foot" neurons with some overlap. The results indicate that most PM set- and movement-related neurons contribute, respectively, to the preparation for and execution of specific limb movements, as opposed to movement per se. Further, the differential distribution of neurons with activity related to hindlimb vs. forelimb movement supports previous indications that PM is topographically organized.

Animals↗

PubMed1975

[Cerebellar movement disorders in monkeys. Comparison of rapidly alternating and slower target movements during cooling of the dentate nucleus (author's transl)].

The effects of short reversible cooling of the dentate nucleus in two groups of 3 and 4 cebus monkeys, with two different types of ipsilateral elbow movements, have been studied. One group was trained to turn a moving handle back and forth rapidly between two mechanical stops, while the second group was trained to move the handle between two target zones. Brief blocking of the dentate nucleus caused a delayed termination of contraction of the agonistic muscles (hypermetria) near the mechanical stop for very rapid, ballistic, alternating arm movements and, consequently, delayed initiation of the antagonistic return movement. The resulting increase of the duration of a single movement was not caused by a reduction of the peak acceleration of the movement. For the slower target movements, dentate nucleus cooling caused shortening of agonistic muscular contraction (hypometria) with corresponding, saccadic movement corrections. The frequency of the "movement tremor" lay between 3 and 5 Hz. The average velocity maxima during dentate cooling did not change. The findings indicate that different types of movements exhibit different disturbances of the movement pattern during the period of functional elimination of the same anatomical structure. The results indicate that the dentate nucleus and cerebellar hemispheres take part in preprogramming movement duration (Kornhuber) for rapid ballistic movements. In slower target movements, the dentate nucleus may be involved in sectional preprogramming of step movements.

Animals↗

PubMed1990

Movement-related phasic muscle activation. I. Relations with temporal profile of movement.

1. The role of phasic muscle activation in determining the temporal properties of human arm movements was studied. The experiments show that subjects can modulate the triphasic electromyographic (EMG) pattern to produce movements of varied temporal structures. 2. Subjects performed horizontal forearm movements in which they varied movement accelerations and decelerations. All movements were of the same amplitude, duration, and peak velocity. A phase-plane (velocity vs. position) template of the desired movement was presented to the subject, who had to reproduce the template by appropriate movement of the forearm. 3. The ratio of the durations of acceleration to deceleration (termed the symmetry ratio, SR) was used as a measure of the temporal structure of the movements. Movements with SRs ranging from 0.4 (short acceleration-long deceleration) to 2.0 (long acceleration-short deceleration) were studied. 4. Subjects modulated the components of the triphasic EMG pattern to produce movements with different temporal profiles. As the SR was increased (increasing acceleration duration-decreasing deceleration duration), the following changes occurred: 1) the duration of the initial agonist burst (AG1) increased while its magnitude decreased; 2) the antagonist burst (ANT1) was progressively delayed relative to movement onset. ANT1 magnitude increased while its duration remained constant; and 3) the magnitude of the second agonist burst (AG2) increased and its duration decreased. 5. The triphasic EMG pattern can be modified to produce movements whose velocity profiles are not the same under simple scaling of duration or magnitude. It is concluded that previously described relations between components of the triphasic EMG pattern and movement parameters, such as amplitude, speed, and duration, are secondary to associated changes in their acceleration and deceleration characteristics.

Acceleration↗

PubMed1990

[Eye movements in schizophrenia--relationships among eye movements under three experimental conditions; closed-eye, pursuit, and exploratory].

In order to investigate the pathophysiology of schizophrenia using psychophysiological indicators of eye movements, this study was conducted to clarify relations among eye movements under three experimental conditions; closed-eye, pursuit, and exploratory eye movements. Thirty-five chronic schizophrenic patients diagnosed by DSM-III-R criteria and 32 normal controls were examined. Horizontal eye movements were recorded electrooculographically with the subjects under two experimental conditions; one with eyes closed ("Closed-eye Eye Movement," Closed-eye EM), and the other with visually tracking a moving pendulum ("Pursuit Eye Movement," Pursuit EM). The closed-eye condition was further divided into two sub-conditions; one with the subjects awake and at rest, and the other with the subjects in the presence of a repetitive sound. Exploratory eye movements were recorded with an eye-mark recording system while the subjects viewing "S"-shaped geometric figures ("Exploratory Eye Movement," Exploratory EM). Indicators of eye movements under the three experimental conditions described above were measured and the correlations among them were investigated. Clinical symptoms in schizophrenics were assessed by BPRS, SANS and SADS and studied with the Factor Analysis method. In the Closed-eye EM, rapid eye movements appeared significantly more frequently and slow ones were less frequent in schizophrenics than in normals under both sub-conditions. The results for schizophrenics did not change significantly with the addition of sound stimuli. In the Pursuit EM, both the number and amplitude ratio of saccades were significantly larger in schizophrenics than in normals, although these indicators gradually decreased in both groups when tasks requiring concentration were demanded. In the Exploratory EM, the number of eye fixations, the total eye scanning length, and the "Responsive Search Score (RSS)," which is the total number of sections on which the eyes fixed during the response to the confirmative question, were all significantly smaller in schizophrenics than in normals. In schizophrenics, there were significant negative correlations between the RSS of the Exploratory EM and the number of rapid eye movements of the Closed-eye EM, the RSS and the number, amplitude ratio of saccades of the Pursuit EM, respectively. On the contrary, in normals, significant positive correlations were found between the number of rapid eye movements and the number of saccades.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Kinematic variability of grasp movements as a function of practice and movement speed.

Grasp movements were studied in six female subjects to determine the effects of practice and movement speed on kinematics and movement variability. Subjects performed four-joint pinch movements of the index finger and thumb, with 200 repetitions at each of three durations (100, 200, and 400 ms). As observed previously, movements of high velocity were performed with bell-shaped, single-peaked velocity profiles. In contrast, slower movements (approximately 200, 400 ms) were performed as a series of two to four submovements with multiple peaks in the associated joint angular velocity profiles. With practice, only the slowest movements (400 ms duration) showed significant reductions in variability of joint end-positions. Surprisingly, variability of finger and thumb joint end-positions did not increase with increasing movement speed as has been observed for arm pointing movements. This was apparently due to reductions in positional variability during deceleration of the movement which offset increases in positional variability during acceleration. Neither practice nor movement speed affected variability of the location of fingertip contact on the thumb, which always occurred on the thumb distal pulpar surface.

Adolescent↗

PubMed1975

Prophase chromosome movements in living house cricket spermatocytes and their relationship to prometaphase, anaphase and granule movements.

Chromosome and granule movements in meiotic prophase and prometaphase have been studied by time-lapse cinemicrography in live spermatocytes of the house cricket, Acheta domesticus. Chromosome movements in prophase cells, up to one hour or more before breakdown of the nuclear envelope, are described. These movements are frequent but saltatory; are based mostly at chromosome ends but also at kinetochores; occur in very intimate association with the inside of the nuclear envelope; are directed towards and away from the extranuclear centres (centrioles); tend weakly to accumulate bivalents round the two centres and reach a velocity of 0.65 micron/sec. Saltatory movements in granules associated with extranuclear asters are remarkably similar to basic characteristics to the intranuclear chromosome movements. Surprisingly, the chromosome movements (and those granules) are reversably blocked by colcemid (but not lumi-colcemid), and yet occur in the apparent absence of an intranuclear envelope. However, kinetochore movements in very early prometaphase are similar in velocity and other respects to prophase movements; later prometaphase movements are clearly slower, and those of anaphase very much slower still. -The prophase movements suggest a two component model for motion: a non-microtubule, linear force producer together withrotubules with a skeletal, orientational role. Arguably, both these components are also necessary for chromosome movements in prometaphase and anaphase.

Animals↗

PubMed1988

Movement-related potentials and control of associated movements.

Previous studies have shown a relationship of the readiness potential (RP) preceding a motor act to motor control, as indexed by eye movement (EM). Greater EM and, therefore, less motor control was associated with increased positivity in preresponse RP components. It was hypothesized that these positive components may reflect processes involved in the inhibition of extraneous or associated movement during the performance of a motor act, especially in younger subjects with less motor development. We developed a finger lift task for detecting irrelevant associated movements (AM) from the responding hand and the nonresponding contralateral hand. During each target finger lift, small movements of the other nontarget fingers from the target hand and the contralateral hand were considered movements that should have been inhibited. Trials for each subject were divided into two bins: associated movement (AM) trials which had movement of target plus nontarget fingers, and trials with only target finger movement detected (NAM). Difference waveforms indicated a positive-going shift on trials with discrete target finger movements (NAM). Age and RP positivity at ipsilateral and posterior regions were significantly correlated. We suggest that, on trials on which associated movements are successfully inhibited, the negativity of the RP is confounded by an overlapping slow positivity. The positivity may be related to the effort needed to inhibit associated movements in order to perform a sharper and more discrete response. This relationship is a function of motor control and, indirectly, of age.

Adolescent↗

PubMed1986

[Comparison of triggered movement-related and self paced movement-related neuronal activities in the frontal agranular cortex].

To examine the functional differences in primate motor cortex (MC), premotor cortex (PM) and supplementary motor area (SMA), single cell activities in these areas were recorded from monkeys performing either visually triggered or self paced key press movement. EMG recordings made clear that activities in finger and hand flexor muscles preceding the triggered or self paced movement were identical and no limb and body muscles were active during performing the task. Neuronal activity changes preceding movement onsets were classified into two categories; a short lead type with the preceding time of less than 300 ms, a long lead type with longer preceding times. In MC, a majority of movement-related neurons (86%) was active phasically and therefore belonged to a short lead type. They exhibited similar activity changes regardless of whether triggered or self paced. In PM, 87% of movement-related neurons were of short lead type. About one third of them were triggered movement specific and another one third were triggered movement predominant. These preferential relation to triggered movement were characteristic in PM. Neurons of SMA were different from MC and PM cells in that as much as a half of them showed the long lead type of activity changes and almost all of these cells were classified into self paced movement dominant or specific. These results suggest that each of these areas have different functional characteristics. PM has more preferential relation to the triggered movement and SMA has more preferential relation to the self paced movement, whereas MC is involved equally in both.

Action Potentials↗

PubMed1978

Perceptions of movement patterns: recall of movement.

The present study attempted to characterize the perception retention, and recall of kinaesthetic information regarding movement sequences (patterns). An attempt was made to draw on and extend conclusions relevant to simple movements (movement amplitude). One group of 10 blindfolded subjects recalled criterion movement patterns that had been actively commanded and 10 subjects recalled passively induced movements. The following conclusions were made. (1) Previous reports of algebraic errors in the recall of simple movement amplitudes are consistency with the finding that criterion perimeter, area, and depth of features were underestimated when recalled. (2) Measures of the accuracy of kinaesthetic perception do not alone account for the generally low level of pattern recall, the large range of individual differences or the underestimation of amplitude. The process of percept formation and of translating a percept into recalled movement are implicated. (3) Conclusions based on the short-term retention and recall of simple movements do not account for the coding, retention, and recall of movement sequences (patterns). (4) Percepts were formed, and patterns were recalled as a sequence of features but not as a sequence of key positions. (5) No direct difference was demonstrated between the recall of actively commanded and passively induced criterion movement patterns. However, the finding of a high gross angle change in the active condition was explained in terms of an unfavourable interaction between corollary discharge and sensory information.

Female↗

PubMed1991

Speech-related body movement in aphasia: period analysis of upper arms and head movement.

The effects of aphasia on coverbal body movement have important implications for the understanding of both normal and pathological speech processes. The related findings were often inconsistent, partly due to inherent methodological difficulties which could be reduced by the use of advanced techniques of movement monitoring (Hadar, 1991). The present study employed a new computerized system, CODA-3, which locates small prismatic markers and computes by triangulation their three-dimensional position at 100 Hz. Movement of the head and the upper arms was monitored in 15 aphasic and normal subjects engaged in speech during a naturalistic interview. Movement analysis was based on automatized identification of successive movement extrema ("period analysis") and the computation of amplitude, duration, and velocity of each period. The results showed higher incidence and amplitude of all body movement in the aphasic population. Fluent aphasics showed this particularly with "symbolic," content-bearing movements, while nonfluent aphasics were higher than controls in both symbolic and "motor" (simple and small) movements. No deficit in the internal organization of movement was seen in the aphasic population. These results indicate that aphasics increase their coverbal movement in compensation for their speech impairment: fluent aphasics compensate primarily for a symbolic impairment, while nonfluent aphasics compensate more for a motor impairment.

Adult↗

PubMed1990

Movement-related potentials accompanying unilateral and bilateral finger movements with different inertial loads.

The present study was aimed at investigating the effect of inertial loading on movement-related potentials (MRPs) recorded from the scalps of normal subjects while performing finger movements. Two experiments were performed. Experiment 1. MRPs preceding and accompanying the execution of voluntary, unilateral finger movements were investigated in 8 subjects under the 3 experimental conditions of: no inertial load, small inertial load (250 g), and large inertial load (400 g). A significant effect of the inertial load on Bereitschaftspotential (BP) amplitude was observed for the 100 msec period preceding movement onset (BP -100 to 0) at precentral electrode sites and following movement onset (N0 to 100) at both precentral and parietal electrode sites. Pairwise comparisons revealed that significant effects were due to differences between the loading and non-loading conditions and not for different amounts of loading. No significant differences were observed for BP onset or early BP amplitudes, indicating that scalp negativity immediately prior to, and during, movement onset is primarily influenced by conditions of inertial loading. Experiment 2. This experiment examined the effect of inertial loading on MRPs for bilateral, simultaneous voluntary finger movements in 10 subjects under conditions of: no inertial load, inertial load applied separately to the left and right fingers, and with identical inertial loads applied to both fingers. No significant effect of inertial load on MRP amplitude was observed. These results are contrasted with those of experiment 1 which show significant effects of inertial loading for unilateral movements and are interpreted in terms of the hypothesis that bilateral movement organization involves 'higher' aspects of motor control than those reflecting adjustment to conditions of inertial loading.

Adult↗