Temporal profile of the directional tuning of the discharge of dorsal premotor cortical cells

Mason, Carolyn R.; Johnson, Michael; Fu, Qing Gong; Gomez, Jose Eduardo; Ebner, Timothy J.

doi:10.1097/00001756-199804200-00007

Cited by 13 publications

(10 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As other studies have found (Mason et al, 1998;Sergio and Kalaska, 1998;Sergio et al, 2005), we observed systematic shifts in PD among multiple single units in MI recorded simultaneously (n ϭ 68 units) while monkeys performed an instructeddelay center-out task ( Fig. 1 A).…”

Section: Evidence For Trajectory Encodingsupporting

confidence: 81%

“…Shifts in preferred direction would thus occur if neurons were encoding force direction. However, this does not explain the shifts in preferred direction that occur before movement in an instructed delay task, as Mason et al (1998) have shown, and as is evident in Figure 1 A.…”

Section: Discussionmentioning

confidence: 69%

“…Last, trajectory encoding may explain the temporal shifts in preferred direction that are often observed in a standard centerout task when measured on a finer time scale (Mason et al, 1998;Sergio and Kalaska, 1998;Sergio et al, 2005). This is a phenomenon that has been underappreciated but calls into question the idea that motor cortical neurons possess a fixed preferred movement direction on a fine time scale.…”

Section: Discussionmentioning

confidence: 99%

“…However, several studies have shown that directional tuning measured on a fine time scale can vary substantially during the performance of a simple reaching task (Mason et al, 1998;Sergio and Kalaska, 1998;Sergio et al, 2005). These results suggest that motor cortical neurons encode temporally extensive representations of movement that may be quite complex.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Encoding of Movement Fragments in the Motor Cortex

Hatsopoulos¹,

Xu²,

Amit³

2007

J. Neurosci.

175

189

View full text Add to dashboard Cite

Previous studies have suggested that complex movements can be elicited by electrical stimulation of the motor cortex. Most recording studies in the motor cortex, however, have investigated the encoding of time-independent features of movement such as direction, velocity, position, or force. Here, we show that single motor cortical neurons encode temporally evolving movement trajectories and not simply instantaneous movement parameters. We explicitly characterize the preferred trajectories of individual neurons using a simple exponential encoding model and demonstrate that temporally extended trajectories not only capture the tuning of motor cortical neurons more accurately, but can be used to decode the instantaneous movement direction with less error. These findings suggest that single motor cortical neurons encode whole movement fragments, which are temporally extensive and can be quite complex.

show abstract

Section: Evidence For Trajectory Encodingsupporting

confidence: 81%

Section: Discussionmentioning

confidence: 69%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Encoding of Movement Fragments in the Motor Cortex

Hatsopoulos¹,

Xu²,

Amit³

2007

J. Neurosci.

175

189

View full text Add to dashboard Cite

show abstract

“…First, neurons change their PD throughout a trial in relation to the behavioral context. Mason et al [11] described neurons in the monkey dorsal premotor cortex, which gradually rotated their PD throughout the instructed delay. They suggested that this PD rotation may reflect aspects of the underlying transformation of a visual stimulus into a directed reaching movement.…”

Section: Discussionmentioning

confidence: 99%

Cancellation of a planned movement in monkey motor cortex

2006

View full text Add to dashboard Cite

Abruptly stopping a planned movement before it has even begun can be crucial to retarding a premature action. In the monkey motor cortex, we report herein that rapid cancellation of a prepared motor act involved the brief activation of neurons representing a movement in the opposite direction (anti-directional activity). When an expected GO signal failed to occur, this opposing anti-directional discharge appeared. It coincided in time with the cessation of the motor cortical activity preparing the requested arm reach. We suggest that functional interactions between subpopulations of neurons eliciting movements in opposite directions could rapidly alter population dynamics, and therefore be used to abruptly cancel a planned movement.

show abstract

Neuronal activity related to eye-hand coordination in the primate premotor cortex

Jouffrais¹,

Boussaoud²

1999

Experimental Brain Research

View full text Add to dashboard Cite

To test the functional implications of gaze signals that we previously reported in the dorsal premotor cortex (PMd), we trained two rhesus monkeys to point to visual targets presented on a touch screen while controlling their gaze orientation. Each monkey had to perform four different tasks. To initiate a trial, the monkey had to put his hand on a starting position at the center of the touch screen and fixate a fixation point. In one task, the animal had to make a reaching movement to a peripheral target randomly presented at one of eight possible locations on a circle while maintaining fixation at the center of this virtual circle (central fixation + reaching). In the second task, the monkey maintained fixation at the location of the upcoming peripheral target and, later, reached to that location. After a delay, the target was turned on and the monkey made a reaching arm movement (target fixation + reaching). In the third task, the monkey made a saccade to the target without any arm movement (saccade). Finally, in the fourth task, the monkey first made a saccade to the target, then reached to it after a delay (saccade + reaching). This design allowed us to examine the contribution of the oculomotor context to arm-related neuronal activity in PMd. We analyzed the effects of the task type on neuronal activity and found that many cells showed a task effect during the signal (26/60; 43%), set (16/49; 33%) and/or movement (15/54; 28%) epochs, depending on the oculomotor history. These findings, together with previously published data, suggest that PMd codes limb-movement direction in a gaze-dependent manner and may, thus, play an important role in the brain mechanisms of eye-hand coordination during visually guided reaching.

show abstract

Temporal profile of the directional tuning of the discharge of dorsal premotor cortical cells

Cited by 13 publications

References 16 publications

Encoding of Movement Fragments in the Motor Cortex

Encoding of Movement Fragments in the Motor Cortex

Cancellation of a planned movement in monkey motor cortex

Neuronal activity related to eye-hand coordination in the primate premotor cortex

Contact Info

Product

Resources

About