ABSTRACT

A new, more elaborated version of a previously suggested time quantum model of mental activity (TQM) is presented. On the basis of new data and a reconsideration of earlier evidence, a simplified derivation of fundamental claims is provided, and it is shown that assumed relations to memory, formerly included as additional postulates, follow directly from the same basic rationale.

The presented version of TQM is based on the assumption that temporal regularities of mental activity result from organizational processes among trains of elementary events which in a ground state are chaotically interrelated. These trains are assumed to become ordered into operative ranges that represent the fundamental periods of hierarchical temporal organization according to three principles:

Segmentation of ranges by rules of uniform chunking.

Range adjustment by (a) truncation of ranges to below the assumed maximum possible length of 30 elementary units and (b) expansion of ranges due to merging of elementary events into integral higher-order units.

Hierarchization of ranges leading to preferred periods by a decomposition of the set of possible ranges into “shells.”

The duration of any admissible period is claimed to be an integer multiple of the duration of an elementary event, the proposed time quantum QTo of about 4.5 ms.

Issues of a full implementation of TQM assumptions in the time domain are discussed. Argument is provided suggesting that a multicarrier model can account for different notions of critical periods such as scanning periods and shifting integration periods as well as for intensity aspects of mental activity. In the final part of the chapter the TQM rationale is tentatively applied to problems of alpha-activity.

294The approach yields specific predictions about the discrete structure of the alpha-band and possible relations to short-term storage capacity. An earlier approach of Lebedev and Lutzky is discussed in the light of these proposals.