 |
 Previous Article | Next Article 
Journal of Neuroscience, Vol 13, 1719-1729, Copyright © 1993 by Society for Neuroscience
Microstimulation in visual area MT: effects of varying pulse amplitude and frequency
CM Murasugi, CD Salzman and WT Newsome
Department of Neurobiology, Stanford University School of Medicine, California 94305-3501.
We have previously shown that perceptual judgements of motion direction are
based in part on the activity of direction selective neurons in
extrastriate visual area MT (Salzman et al., 1990, 1992). In those
experiments, we applied low-amplitude microstimulation pulses (10 microA,
200 Hz) to clusters of MT neurons whose preferred directions were similar.
The effect of microstimulation was to bias the monkeys' choices on a
direction discrimination task toward the preferred direction of neurons at
the stimulation site. The results suggest that microstimulation generated a
directionally specific cortical signal by activating selectively neurons
near the electrode tip. To test this notion more directly, we have now
examined the behavioral effects of varying current amplitude, current
frequency, and electrode position. In the majority of experiments, the
directional bias in the monkeys' choices was reduced or eliminated as
current amplitude increased to 80 microA. In addition, 80 microA
stimulating pulses frequently impaired overall performance as measured by
the percentage of correct responses. This decrement in performance
indicated that 80 microA pulses introduced "noise" into the neural
circuitry encoding motion direction, presumably by increasing current
spread to activate a larger population of neurons representing all
directions of motion. In contrast, increasing current frequency to 500 Hz
(10 microA pulses) preserved the directional specificity of
microstimulation effects. The precise position of the stimulating electrode
also influenced the magnitude of microstimulation effects; in some cases,
differences in position on the order of 100 microns determined whether an
experiment yielded a very large effect or no effect at all. Thus,
directionally specific activation of cortical circuitry within MT can be
disrupted by increases in current spread or by small changes in electrode
position. These observations suggest that the effects of low-amplitude
microstimulation depend upon direct activation of a well-localized
population of neurons.
This article has been cited by other articles:
|
|
|
|
 
B. C. Voigt, M. Brecht, and A. R. Houweling
Behavioral Detectability of Single-Cell Stimulation in the Ventral Posterior Medial Nucleus of the Thalamus
J. Neurosci.,
November 19, 2008;
28(47):
12362 - 12367.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. E. Winkowski and E. I. Knudsen
Top-Down Control of Multimodal Sensitivity in the Barn Owl Optic Tectum
J. Neurosci.,
November 28, 2007;
27(48):
13279 - 13291.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. L. Kimmel and T. Moore
Temporal Patterning of Saccadic Eye Movement Signals
J. Neurosci.,
July 18, 2007;
27(29):
7619 - 7630.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
N. A. Fitzsimmons, W. Drake, T. L. Hanson, M. A. Lebedev, and M. A. L. Nicolelis
Primate Reaching Cued by Multichannel Spatiotemporal Cortical Microstimulation
J. Neurosci.,
May 23, 2007;
27(21):
5593 - 5602.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
B. Krekelberg, R. J. A. van Wezel, and T. D. Albright
Interactions between Speed and Contrast Tuning in the Middle Temporal Area: Implications for the Neural Code for Speed.
J. Neurosci.,
August 30, 2006;
26(35):
8988 - 8998.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
E. J. Tehovnik, A. S. Tolias, F. Sultan, W. M. Slocum, and N. K. Logothetis
Direct and Indirect Activation of Cortical Neurons by Electrical Microstimulation
J Neurophysiol,
August 1, 2006;
96(2):
512 - 521.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. C. Bradley, P. R. Troyk, J. A. Berg, M. Bak, S. Cogan, R. Erickson, C. Kufta, M. Mascaro, D. McCreery, E. M. Schmidt, et al.
Visuotopic Mapping Through a Multichannel Stimulating Implant in Primate V1
J Neurophysiol,
March 1, 2005;
93(3):
1659 - 1670.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Liu and W. T. Newsome
Correlation between Speed Perception and Neural Activity in the Middle Temporal Visual Area
J. Neurosci.,
January 19, 2005;
25(3):
711 - 722.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Butovas and C. Schwarz
Spatiotemporal Effects of Microstimulation in Rat Neocortex: A Parametric Study Using Multielectrode Recordings
J Neurophysiol,
November 1, 2003;
90(5):
3024 - 3039.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. J. Nichols and W. T. Newsome
Middle Temporal Visual Area Microstimulation Influences Veridical Judgments of Motion Direction
J. Neurosci.,
November 1, 2002;
22(21):
9530 - 9540.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. H. Britten and R. J.A. van Wezel
Area MST and Heading Perception in Macaque Monkeys
Cereb Cortex,
July 1, 2002;
12(7):
692 - 701.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
W. Bair, E. Zohary, and W. T. Newsome
Correlated Firing in Macaque Visual Area MT: Time Scales and Relationship to Behavior
J. Neurosci.,
March 1, 2001;
21(5):
1676 - 1697.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. W. Bisley, D. Zaksas, and T. Pasternak
Microstimulation of Cortical Area MT Affects Performance on a Visual Working Memory Task
J Neurophysiol,
January 1, 2001;
85(1):
187 - 196.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. M. Groh, R. T. Born, and W. T. Newsome
How Is a Sensory Map Read Out? Effects of Microstimulation in Visual Area MT on Saccades and Smooth Pursuit Eye Movements
J. Neurosci.,
June 1, 1997;
17(11):
4312 - 4330.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. Salzman and W. Newsome
Neural mechanisms for forming a perceptual decision
Science,
April 8, 1994;
264(5156):
231 - 237.
[Abstract]
[PDF]
|
|
|
|
|
|
|
E Zohary, S Celebrini, K. Britten, and W. Newsome
Neuronal plasticity that underlies improvement in perceptual performance
Science,
March 4, 1994;
263(5151):
1289 - 1292.
[Abstract]
[PDF]
|
|
|
|
