The Journal of Neuroscience, January 4, 2006, ():
Attention Lights Up New Object Representations before the Old Ones Fade Away
J. Neurosci. Khayat et al.
26: 138
Supplemental data
Files in this Data Supplement:
- supplemental material -
Supplemental material
- supplemental material
-
Legends
Fig. 4. Recording technique. a, The signal coming from the chronically implanted electrodes is amplified and filtered between 750 and 5000 Hz (Filt1). Single unit activity (SUA) is obtained by detecting times at which Filt1 reaches a threshold with a Schmidt trigger. To obtain MUA, Filt1 is full-wave rectified (negative potentials become positive), low-pass filtered at 500 Hz (Filt2), and sampled at a rate of 1000 or 1100 Hz. b, In this case SUA can be recorded by suitable positioning of the trigger level (red dashed line). The shapes of the action potentials that are detected in this way are similar (not shown). The inset shows the signals at higher temporal resolution. The shaded region that is superimposed on Filt1 replicates MUA, to illustrate that it follows the signal’s envelope. MUA is large whenever neurons in the vicinity of the electrode fire action potentials.
- supplemental material
-
Fig. 5. Population responses during normal trials of sites stimulated with an optimal (N=44, left) and sub-optimal (N=15, right) oriented curve segment. MI, modulation index.
- supplemental material
-
Fig. 6. Stratification procedure. a, (Upper) Stimulus on a normal trial (left) and on a switch trial (right). T, target curve. D, distractor curve. (Lower) Distribution of eye positions (0.2º x 0.2º bins) while the monkey directed his gaze to the fixation point (cross). The eye positions in trials with stimulus T (n = 206) (left) are compared with the eye positions with stimulus T→D (n = 73) (center). The stratified distribution of eye positions (n = 69) was obtained by removing excess trials in every bin (right). b, Same as above but for different stimuli. c, Population responses (N=59) during switch trials (thick traces) and normal trials (dotted traces), after the stratification procedure. The magnitude of response enhancement (light grey area) is stronger than that of the response suppression (dark grey area). Lower, curves that were fitted to the response difference between stimuli D and D→T (in red), and stimuli T and T→D (in black), in order to determine the latency of enhancement and suppression, respectively.
- supplemental material
-
Fig. 7. The latency estimate is independent of the number of trials. Comparison of the latency of enhancement (or suppression) that is computed by fitting a curve to the difference in responses averaged across 100% of the trials (on x-axis) and across 50% of the trials (on y-axis). Red, latency of enhancement. Black, latency of suppression. Median Latenh100% = 134 ms; Median Latenh50% = 138 ms. Median Latsupp100% = 201 ms; Median Latsupp50% = 195 ms.
.gif?ad=17923&adview=true)
