Meaning and Exemplification of adaptation level; theory of pooling and weighting

Helson criticizes current perceptual theories for their lack of the quantitative formulations that are necessary for the mature development of any science; and he suggests his method and theory may help to supply this need. One of the salient characteristic of organism, he maintains, is the tendency to categorize their experience in terms of some kind of order.

The way in which the organism achieves such an order is by establishing subjectively some neutral, indifferent, region in its quantitatively arrayed experiences. Using the whole gamut of stimulus magnitudes to which he is accustomed as a frame for his judgments, the individual established an average really a small region of magnitude, as kind of standard. Such a neutral region in the hefting of weights would be the small range of objective weight values within which the subject reported that the weight seemed neither heavy nor light but medium. This neural or medium position is called the adaptation level of the subject.

For every moment of stimulation, in Helson’s view, there is an adaptation level; and this level changes in time and with the varying conditions of stimulation.

Pooling; pooling is therefore a physiological as well as a psychological phenomena; it may occur even below the level where conscious judgments occur.

According to Eiser 1986, Helson defines adaptation level as a weighted logarithmic mean of all past and present stimulation on a given dimension. As each new stimulus is presented, it will be averaged into the computation on a new Adaptation level.