Sentences with phrase «saccade activity»

(E) Average memory - guided delayed - saccade activity for the same example cell shown in (C).

A similar response is also evident during the self - timed saccade activity (blue, left), although the cause is likely due to a central saccade bringing the RF to encompass the peripheral target instead of target onset since first saccades are not included in the rhythmic analysis (Figure 4C).

Not exact matches

By recording neuronal activity in monkeys as they performed tasks that caused saccades, Dr. Christopher Pack has shown that there are waves of activity that cross specific vision processing areas of the brain in defined patterns, and that these patterns are reorganized by saccadic eye movements.

The observation that activity is only correlated with the present interval implies that the correlations observed prior to central saccades to timing do not reflect past or future planning of peripheral saccades.

For example, if LIP activity were strongly modulated by both central and peripheral saccades, then a firing rate reconstruction based on only one of those saccades would poorly predict peri-saccadic activity for the other saccade.

Although the predominant feature of activity modulation during self - timed saccades is a near linear decline in firing rate over time, other modulations are clearly present.

Specifically, we looked at whether activity locked to a particular saccade could completely explain the peri-saccadic activity aligned to the other saccade by generating firing rate predictions of each saccadic alignment on the basis of the other (Figure 5A) and behavioral variability.

Brief increases in activity just prior to saccade onset are followed by short intervals of decreased activity at the time of saccades.

Overall correlations were significant for precentral and postperipheral saccade aligned activity and increased from 0.050 and 0.076 to 0.145 and 0.157, respectively.

In order to determine what factors are associated with firing rate changes, we generated a prediction of neural activity by convolving observed neural activity aligned with one saccade direction with the intersaccade distribution times aligned with the other saccade direction.

Around the time of saccade onset (± 100 ms), the activity displays distinct modulations.

A good fit between the predicted rates (green traces) and the observed firing rates (red and blue traces) would indicate that activity locked to a particular saccade can largely explain the firing rate changes seen in the cyclical task.

(A and B) Average combined population activity, grouped by interval length, aligned to central saccades (A) and peripheral saccades (B).

The same analysis is then repeated using activity aligned to central saccades.

The difference between this prediction and the observed firing rate for activity aligned to central saccades indicates how well activity associated with peripheral saccades can completely explain task - related modulations in activity.

If LIP activity strictly reflected a broad timing system (like those described by centralized timing models), its activity would have a consistent relationship with time irrespective of saccade direction.

Therefore, LIP activity is likely related to motor planning rather than saccade metrics.

We recorded activity of 146 saccade - related neurons that were found in the intermediate and deep layers of the SC (about 0.5 — 3 mm below the dorsal surface).

Three different activity measures were used to quantify the magnitude of the saccade - related bursts of SC neurons for movements towards the center of their movement field as a function of their rostral - to - caudal location in the SC motor map: A) number of spikes in the burst, B) mean firing rate and C) peak spike density.

Citation: Goossens HHLM, van Opstal AJ (2012) Optimal Control of Saccades by Spatial - Temporal Activity Patterns in the Monkey Superior Colliculus.