Stimulus variation and sequential judgements of duration

When a series of reproductions of an interval is made in the absence of a standard the judgements progressively lengthen. The similarity between stimulus conditions in this type of time estimation experiment and the conditions which produce a decrement in human vigilance is discussed. It is argued that failure to detect cues for the passage of time reduces the amount of time perceived to elapse. Reproduced judgements must consequently be increased in length to match remembered standards. The hypothesis is then made that the kind of variation in background stimulation which facilitates vigilance should increase the frequency of detection of cues for duration and reduce reproduced judgements. This hypothesis is tested with 80 subjects and a reversal of the serial reproduction effect is found on trials with changed background conditions.     

Object perception and object-directed reaching in infancy

Five-month-old infants were presented with a small object, a larger object, and a background surface arranged in depth so that all were within reaching distance. Patterns of reaching for this display were observed, while spatial and kinetic properties of the display were varied. When the infants reached for the display, they did not reach primarily for the surfaces that were nearer, smaller, or presented in motion. The infants reached, instead, for groups of surfaces that formed a unit that was spatially connected and/or that moved as a whole relative to its surroundings. Infants reached for the nearer of two objects as a distinct unit when the objects were separated in depth or when one object moved relative to the other. They reached for the two objects as a single unit when the objects were adjacent or when they moved together. The reaching patterns provided evidence that the infants organized each display into the kind of units that adults call objects: manipulable units with internal coherence and external boundaries. Infants, like adults, perceived objects by detecting both the spatial arrangements and the relative movements of surfaces in the three-dimensional layout.     

Electrophysiologic studies of alcohol dependent patients

Electrophysiological methods were used to examine 52 ward patients with a long history of alcohol abuse. Alertness fluctuations were much more common in the EEG than among the healthy control subjects. 86.5% of the ENG findings were abnormal and indicated demyelinisation in most cases. The latence times of the brain stem potentials were longer than normal in about half of the patients and were definitely pathological in 13.5%. There was no statistical correlation between drinking habits and the results of the examination. Unknown pathogenetic factors are therefore suspected. The polytopic pattern of damage necessitates the use of a broad range of signostic techniques.     

Neurophysiologic findings in chronic alcohol abuse

Neurophysiological examinations of 100 long term alcohol dependent patients who were having neuropsychiatric treatment, showed symptoms of polytopic damage of the peripheral and central nervous system. The results show that for recognition of the damage an extensive diagnostic programme must be used.     

Auditory food cue conditioning: Effects of spatial contiguity and taste quality

The effects of spatial location of an auditory stimulus and quality of a potentiating taste on the aversive conditioning of an auditory food cue were investigated. In Experiment 1 rats ate salty food activating a tone from a speaker either in (spatially contiguous with) or displaced from the food and were then made ill. It was found that spatial contiguity during conditioning resulted in avoidance of food with a contiguous or a displaced tone in testing, and spatial displacement during conditioning resulted in avoidance of food only if the tone was also displaced in testing. Experiment 2 was identical, except rats ate salty, bitter, or sweet food with a displaced tone during conditioning and testing. The salty and bitter food groups demonstrated an avoidance of noisy food relative to the sweet food group. These results indicate that spatial contiguity interacts with taste quality in the conditioning of nongustatory food cues.     

Pure optic ataxia and visual hemiagnosia – extending the dual visual hypothesis

Goodale and Milner's two visual system hypothesis is an influential model for the understanding of the primate visual system. Lesions of either the ventral (occipito‐temporal) or the dorsal (occipito‐parietal) stream produce distinct and dissociated syndromes in humans: visual agnosia is typical for ventral damage, whereas optic ataxia (OA) for dorsal damage. We studied the case of a 59‐year‐old left‐handed woman with a circumscribed lesion around the left posterior occipital sulcus, extending to the underlying white matter. Initially, she presented with a central visual field OA, which regressed to an OA to the right visual hemifield during the 3 months observation period. In addition, tachistoscopic experiments showed visual hemiagnosia to the right visual hemifield. In line with the findings of the neuropsychological experiments, the analysis of the structural MR data by means of a trackwise hodologic probabilistic approach revealed damage to the left superior longitudinal fasciculus and to the left inferior longitudinal fasciculus, indicating an impairment of both the dorsal and the ventral stream. The combination of OA and visual hemiagnosia in the same patient has never been previously described. The present case study thus provides further insights for the understanding of visual processing.     

Complex Environmental Reactions,as a New Concept to Describe Spontaneous “Paranormal” Experiences

A systemic phenomenological model that assumes the movability of the Cartesian cut is proposed and elucidated by means of a single exploratory case study. The model assumes that a continuum from purely psychosomatic disorders to RSPK cases exists. The degree of externalization (locus of control) of the affected person serves as an ordering parameter for the location of the Cartesian cut. It turns out that the dynamics of the disorder develops in four phases, like in the RSPK-model of the MPI. However, in contrast to the decline phase of the RSPK cases (because of the NT-axiom), CER cases lead to petrification of the complaints.     

Using mu rhythm desynchronization to measure mirror neuron activity in infants

The Mirror Neuron System hypothesis stating that observed actions are projected onto the observer’s own action system assigns an important role to development, because only actions mastered by the observer can be mirrored. The purpose of the present study was to investigate whether there is evidence of a functioning mirror neuron system (MNS) in 8-month-old infants. High-density EEG was used to assess the mu rhythm desynchronization in an action observation task where the infants observed a live model. To reduce noise, ICA decompositions were used. The results show a higher desynchronization of the mu rhythm when infants observed a goal-directed action than when they observed a spatially similar non-goal-directed movement. The localizations of the sources are in agreement with those proposed by the MNS hypothesis. This indicates that the MNS is functioning at this age.