Psychometric functions generated by single electrocutaneous stimuli yielded a median coefficient of variation ( (jI J.l ) of 0.23. These data are consistent with other psychometric data recently reported by us which yielded (jIll ratios of this size. The data are discussed and related to conflicting data reported in the recent literature indicating coefficients of variation for this mode of stimulation which are only 1/3 as large. Evidence is presented for partial temporal summation (time-intensity reciprocity) for electrocutaneous stimuli ranging from 175 to 610 microseconds. The data are best fitted by the equation I x t a =k, where a is approximately 0.57. This equation and exponent also fit summation data reported by the same authors who report finding steep psychometric functions. Clearly, then. the mechanism responsible for the very limited temporal summation found for electrocutaneous stimulation and the mechanism responsible for very steep psychometric functions are not identical. The discussion also includes speculation regarding possible mechanisms and suggestions for research.

Breger, L.: Function of dreams. J. abnorm, soc. Psychol. Monogr. 72: 1-28 (1967 This paper is based on the assumption that EEG a-rhythm is concomitant with divergent thinking. This assumption is suggested here as an alternative to the usual assumptions that a-rhythm represents a lack of visual perception and of visual imagination, or a lack of arousal state. The theoretical considerations for this new assumption will be discussed elsewhere, where it will be shown that it accounts for most of the known empirical facts about the relationship between the appearance and disappearance of

A comparison was made between two measures of somatosensory sensitivity, response probability, and reaction time to electrocutaneous constant current pulses of 350-microsec duration. The psychometric functions are steeper than those obtained for other sensory modalities. Similarly, the reaction-time/intensity functions are also steeper than those obtained in other modalities, i.e., larger decreases in reaction time as a function of small increases in stimulus intensity. Ss exposed to a broad stimulus range, including high intensities, yield psychometric and reaction time functions displaced into a higher intensity region than when they are exposed to a narrow low-intensity range of stimuli. The data are discussed in terms of a decision-theory model of reaction time.*The authors would like to acknowledge the aid of Jacob Gutgold in building and servicing the equipment, and thank the research committee of Bar-Ban University for the research funds that made this study possible. We also wish to thank Drs. Bruder