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The present study investigated the applicability of the Law of Initial Value (LIV) for heart rate (HR) responses evoked by a nociceptive stimulus in neonatal sleep states. Ten infants were tested during Quiet and Active Sleep. In concordance with the LIV there was a significant inverse correlation for all Ss in Active Sleep between HR change and prestimulus HR values; the average correlation was -.76, the average slope -.48. In Quiet Sleep, which had a small prestimu1us HR range, this relationship was significant only for some Ss. Equating for prestimulus HR values, no significant difference existed in the magnitude of average HR response in Active Sleep vs Quiet Sleep. It was concluded that for nociceptive stimuli the initial HR value is a better predictor than the behavioral sleep state of the magnitude of HR response. It is suggested that the LIV depends largely on the modality and strength of the stimulus and the width of the prestimulus HR range. [ABSTRACT FROM AUTHOR]

The ultrastructure of the paired nerves, previously called frontal organ or X-organ, in copepod crustaceans was investigated. These nerves, running from the anterior margin of the brain to the frontal edge of the animals, are found to contain the dendrites of three types of morpho-logically different sensory neurons. The first unit consists of two dendrites (distinguished by their myelinization) leading to two small hairs on the front. Their detailed structure was not investigated. The second unit consists of a few large dendrites ending in branching cilia. The latter are surrounded by a specialized glial cell. The ciliary branches are regularly sized and arranged. The third unit consists of c. 17 dendrites ending with cilia at the cuticle. The cilia are split into irregular branches which are buried in modified epidermal cells which, in the case of Calanus, are connected with cuticular pores. By analogy with other presumed chemosensory organs in the Arthropoda, the second and the third unit are considered, on a morphological basis, to be chemoreceptors. The second unit receives internal stimuli. Because it resembles other X-organs in the Crustacea, all X-organs could have the same function. The third unit is thought of as receiving external stimuli. [ABSTRACT FROM AUTHOR]

The article evaluates the Bender-Gestalt Visual Motor Test. The Bender-Gestalt test was built on the premise that accurate visual-motor perceptual behavior is a skillful act. This skillful perceptual act is considered to involve sensory reception, central neural interpretation, and motor reproduction (hand drawing) by the perceiving subject of the test stimulus objects. The premise goes further and states that this total perceptual process can be distorted by neural injury, by variations in the intellectual level, and by maladjustments in the emotional organization of the perceiving subject.