Estimation of time intervals in an array of intervals. I.

It has been shown that when man estimates the duration of separate brief time intervals(300-1,000ms), elements of a certain array of time intervals within the same range, the estimation is not affected by changes in the other elements of the array. The complex light and dark intervals are considerably underestimated. The separate estimation of two elements (light and dark interval) from the array has shown that the sum of the separate responses exceeds the estimation when the same two elements have to be estimated together as a total interval. The results could be explained by the existence of at least two "internal clocks".