Competitive Inhibition Models of Lexical–Semantic Processing: Experimental Evidence

A modified Neisser word-search (search II) was administered to patients with Parkinson's disease (PD), and significant deficits were found. Given the assumption that the processes are lexical, we interpret the results as support for the claim that there is competition between semantically related words in speech production (Wheeldon, 1989). A related verbal task-switching experiment (continuous series II) is also presented. Although PDs are impaired on task switching, there are double dissociations between verbal task switching (continuous series II) and lexical retrieval (search II). The relationship between performance on these tasks and on verbal fluency is also addressed.     

Effects of diagnostic classification systems on clinical hypothesis-generation

In this study it was determined whether (a) classification as opposed to absence of classification has an effect on the quality of clinical hypotheses (b) the DSM-III-R and the CBCL have a different effect on the quality of clinical hypotheses, and (c) the potential difference between the DSM-III-R and the CBCL is moderated by the different number of syndromes identified by these systems. To investigate these questions, an experiment was conducted in which 86 clinicians generated hypotheses for six cases. The clinicians were divided into a DSM-III-R, a CBCL, and a control group. Of the six cases, two were classified by both classification systems as one syndrome, two were classified as one syndrome by the DSM-III-R but as two syndromes by the CBCL, and two were classified as two syndromes by the DSM-III-R but as one syndrome by the CBCL. The quality of the hypotheses was determined by means of four dependent variables selected from an overview of qualitative criteria: explanatory value, redundancy, possibility of operationalization, and specificity. No differences between the CBCL and the control groups were found. The DSM group performed better than the control group regarding explanatory value and redundancy. The DSM-III-R group also scored better than the CBCL group regarding explanatory value, particularly when the number of identified syndromes was two for the CBCL and one for the DSM-III-R.     

An injection olfactometer for humans and a new method for the measurement of the shape of the olfactory pulse

An injection olfactometer for human psychophysical experiments is described. The olfactometer is capable of presenting, either mono- or birhinally, single odorants and binary mixtures. The pulse form of the olfactory stimulus at the exit of the olfactometer approaches a rectangular form, which makes the olfactometer well suited for olfactory reaction time measurements. Since stimulation periods are independent of the subject’s inhalation, time-intensity measurements over prolonged periods of time are possible as well. In the second part of this paper, a new technique is described for the measurement of the stimulus pulse form at the exit of the olfactometer.     

Field dependence and the effect of REM deprivation on thirst.

Recently a number of studies have concerned the possible function of rapid eye movement (REM) sleep and the mastery of stress. The present study was designed to explore the possibility that REM sleep might play a function in reducing the potency of a stressful physiological stimulus, thirst, as well as the possibility that such a function might be specific to individuals falling at different points along the field-dependence dimension. While there was no difference between REM deprivation and non-REM awakening nights in subsequent morning thirst, there was a significant interaction between field dependence and night on morning thirst measures for 10 college students. These results are discussed in light of previous work on stylistic differences in dreaming and their possible role in adaptation to stress.     

The integration of motivational information: A conjoint measurement analysis

Within Anderson's (1974a, b, c, 1978b) information integration theory, the integration of motivational information was investigated by means of conjoint measurement techniques. Eighteen university students were asked to judge hypothetical co-students characterized by three features (intelligence, motivation and the extent to which they study) according to their chances to pass. Both rank order data and ratings were obtained. The orderings of most subjects could be represented very well by an additive model. A polynomial regression procedure was applied to determine the shape of the response function for the ratings. As this function was quite linear for all subjects, the ratings could be said to form an interval scale.     

Sleep,activity, temperature,and performance: Techniques for long-term monitoring in the mouse

This paper describes a test chamber, a food acquisition task, and a training procedure for the long-term testing of an implanted mouse in a circadian rhythm experiment. For the training phase, a special-purpose controller is provided to a single cage. For the experimental phase, behavioral, electrophysiological, and environmental measures are collected by means of a mini-computer.     

MANUAL ACTIVITY DURING SPEAKING IN APHASIC SUBJECTS*

Samples of free conversations were recorded in 6 normal and 12 aphasic subjects. Manual activity during speech was observed. Groups were shown to behave in an opposite way for the verbal and nonverbal measures: while aphasic subjects' verbal behavior is impaired, they produce more speech-related movements than normals. No differences appear concerning other movements (automanipulation, hand-to-hand posture, miscellaneous movements). Analysis of the aphasie group reveals no difference between the fluent and the nonfluent aphasies. Verbal fluency is shown to be a non-critical factor in the explanation of gesture production. Increased gestural production in aphasies may be interpreted according to the hypothesis that gestures are cues for the difficulties the speaker experiences in the verbal encoding process.     

Inhibitory avoidance deficit following short-term adrenalectomy in the rat: the role of adrenal catecholamines

Impaired retention of an inhibitory avoidance response was observed in rats subjected to adrenalectomy (ADX) up to 120 hr before the single learning trial. Corticosterone substitution failed to normalize this behavioral deficit. Rats ADX 240 hr prior to the learning trial showed a normalized behavior. Adrenomedullectomy (ADXM) 48 or 240 hr before learning caused a similar impairment as in short-term ADX rats. The 240-hr ADX rats subjected to corticosterone substitution showed the same behavioral deficit as short-term ADX rats or ADXM ones. Immediate postlearning subcutaneous injection of adrenaline in a dose range of 0.005-5.0 micrograms/kg or of noradrenaline (0.005-0.5 microgram/kg) to 48-hr ADX rats resulted in a dose-related improvement of later retention behavior. Higher doses of catecholamines were less or ineffective. Postlearning treatment of 48-hr ADXM rats with adrenaline (0.5-500 micrograms/kg) caused a similar pattern of behavioral changes. It is concluded that adrenal catecholamines play an important role in the modulation of consolidation of memory. In addition, the high circulating ACTH levels that follow long-term ADX may correct for the behaviorial deficit induced by the absence of adrenomedullary catecholamines.     

Father-child relationships from the preschool years through mid-adolescence

In this study, we examined variations in fathering and father-child relationships from the children's preschool years through mid-adolescence. One hundred seventy-seven fathers with first-born children ages 4, 8, 12, and 16 years responded to five sets of questionnaires tapping four domains of childrearing: practices, attitudes, parental role involvement, and role satisfaction. A multivariate analysis of variance identified significant variability among the four age groups in fathers' use of acceptance in childrearing practices, role involvement (frequency and task sharing), satisfaction with paternal role performance, and attitudes about the modifiability of child behavior. The results contribute new information about the nature of fathering throughout the childhood years and adolescence and provide additional support for the view of parenting as dynamic and responsive to the developmental level and gender-related characteristics of the child.     

Differential effects of priming at the encoding and judgment stage

Two experiments investigated whether the direction of priming effects depends on the processing stage at which the individual links the prime to a trait that is applicable to the evaluation of an ambiguously described target person. In line with previous research, it is hypothesized that assimilation effects will emerge when primes are processed in terms of a trait concept that is applicable to the encoding task. However, when the primes are not processed in applicable trait terms, they may still affect subsequent Judgments if the individual recalls the prime when judging the target along a trait dimension. In this case, the primes may serve as an anchor, resulting in contrast effects. Two experiments, in which subjects were primed with names of prototypically nice or hostile famous individuals under instructions that did or did not prompt subjects to process the prime in applicable trait terms, supported these hypotheses. Implications for the emergence of priming effects in everyday social interaction are discussed.