Cognitive slowing in decision tasks in early and advanced Parkinson's disease.

Ten untreated patients with recently diagnosed Parkinson's disease (PD), 9 treated patients with more advanced pathology, and 17 matched normal controls were investigated with three reaction tasks with increasing cognitive load but identical motor requirements: simple reaction, choice reaction with indicative stimuli, and choice reaction with ambiguous stimuli. Times required until a home key was released (= reaction time) and from then until a response key was pressed (= movement time) were recorded. Estimates of pure decision time (overall response time minus movement time in a simple reaction time task) revealed a difference between advanced and early PD patients. Advanced PD patients showed an overall slowing of decision time in the reaction time tasks, but the effect of the cognitive load of the tasks on the decision time was comparable to a control group. The untreated early PD patients performed quite normally in the more simple decision tasks but showed a disproportionate slowing of decision time in tasks with higher cognitive load.     

The use of prediction data in understanding delinquency

Predicting delinquency is valuable for understanding the course of crime, factors that influence its course, and the identification of markers that signal deviant processes. In addition, prediction data are relevant for judicial and clinical decision making. This article summarizes research findings on the prediction of delinquency. In the realm of early childhood behaviors, there is consensus that aggression (especially in conjunction with hyperactivity), drug use, truancy, lying, stealing, general problem behaviors, and poor educational achievement all predict later delinquency, albeit to varying degrees, with composite prediction scales yielding the highest degree of accuracy. In addition, studies show a reasonable consensus that the following family factors also predict delinquency: poor supervision, lack of involvement by parents, poor discipline, rejection by a parent, parental criminality and aggressiveness, marital problems, parental absence, and poor parental health. Variables reflecting socialization processes predicted later delinquency as well as children's early behavior. Although studied less frequently, youngsters' association with deviant peers is also predictive of delinquency.     

Developmental sequences in the age of onset of disruptive child behaviors

Retrospective and prospective reports of the onset of disruptive child behaviors were analyzed in a sample of clinic-referred boys. The younger boys (ages 7–9 years), compared with the older boys (ages 10–12 years), showed the highest level of disruptive behavior and, judging from mothers' reports, had the fastest progression of onsets from less serious to more serious problem behaviors. Despite some overlap, developmental sequences in problem behavior within the domains of hyperactivity/inattention, oppositional behavior, and conduct problems were similar across the two age groups. This was also the case for developmental sequences of overt or confrontive problem behaviors and covert or concealing conduct problems. Sequences of the onset of oppositional behavior and conduct problems were validated through prospective data, based on the information from mothers, teachers, and boys themselves. The implications of the findings are discussed for the formulation of developmental pathways of behavior and the analysis of causal factors.     

The utility of differentiating between mixed and pure forms of antisocial child behavior

This study examined the utility of classifying boys on the basis of a typology of antisocial behavior. A group of 195 boys, aged 10–17, was divided into four mutually exclusive groups based on their pattern of antisocial behavior. Stealing and fighting were chosen as criteria to define the four groups: (a) boys who fought but did not steal (Exclusive Fighter Group), (b) boys who stole but did not fight (Exclusive Theft Group), (c) boys who stole and fought (Versatile Antisocial Group), and (d) boys who did neither (Remaining Group). A multimethod-multirespondent study of these boys showed that (a) the Exclusive Fighter Group tended to score high on a range of overt antisocial behaviors and were relatively little involved in delinquency; (b) the Exclusive Theft Group tended to score high on some overt antisocial behaviors and were much involved in delinquency; (c) Versatile Antisocial youths scored highest among all groups on almost all overt and covert antisocial behaviors, and in terms of delinquent acts. The Versatile boys came from families with the most disturbed child-earing practices.The authors are indebted to Gerald Patterson for his inspiration and encouragement through-out the study. They acknowledge the most helpful comments they have received during earlier drafts of this paper from Drs. John Reid, Magda Stouthamer-Loeber, and Mark Weinrott.The paper was presented at the annual meeting of the American Society of Criminology, Denver, Colorado, November 10, 1983. The study has been funded by the Center for Studies in Crime and Delinquency, National Institute of Mental Health, Grants MH 32857 and MH 37940.     

Interhemispheric integration of compound nouns: effects of stimulus arrangement and mode of presentation

Normal subjects had to name German compound nouns which were presented tachistoscopically. The compound nouns were displayed either unilaterally to the left or right visual field or bilaterally with one element to each visual field. In the bilateral condition a distinction was made as to whether familiar or unfamiliar arrangement of the elements was used. Representation in print was compared with pictorial representation of the compound nouns. A right visual-field superiority was observed with printed representation, but no laterality effects with pictorial representation. Bilateral processing was superior to unilateral processing. Within the bilateral conditions, the familiar arrangement of the elements yielded a significantly better performance than unfamiliar arrangement. This difference can be explained by reading habits and/or by different styles of interhemispheric integration.     

Pupillary responses to syntactic ambiguity of sentences

Pupillary responses have proven to be reliable physiological correlates of cognitive effort in a variety of tasks, including language processing. To investigate the relation between psychological and syntactic complexity 20 syntactically ambiguous sentences, balanced for bias, were presented to 16 subjects, while their pupil size was continuously measured. These sentences could be read as verb oriented (syntactically more complex) or object oriented (syntactically less complex). Principal components analysis of pupillary movements revealed that verb-oriented readings, resulted in greater pupillary dilations than object-oriented readings, indicating that syntactically more complex sentences, as determined via a formal grammar, require greater cognitive effort in processing. This is viewed as further evidence for the notion that syntactic and psychological complexity are related. High- and low-bias sentences did not induce comparable differences in pupillary movements, indicating that the "multiple meaning theory" may have to be modified.     

Length of Group Membership, Assumed Similarity, and Opinion Certainty: The Dividend for Veteran Members

Newcomer and veteran fraternity members indicated their own attitudinal position on each of 10 issues and then estimated the positions of either prospective or full in-group members or they received no opportunity to project. All subjects then rated their certainty about their own position on each issue. As expected. both newcomers and veterans assumed greater attitudinal similarity to in-group members than to prospective members. Moreover, projection onto in-group members only increased the opinion certainty of veteran members. Their certainty correlated with the percentage of their friends who were in-group members. Newcomers' certainty increased only after projection onto the lower status recruits. Membership tenure and social identity are discussed in relation to attitudinal projection and the goals of social comparison.     

Bisecting RT with lateralized readiness potentials: Precue effects after LRP onset

Recent work has sought to use the time at which the Lateralized Readiness Potential (LRP) first develops (LRP onset) as a temporal landmark to bisect experimental effects on reaction time (RT). Many studies have found experimental effects on the time between the signal and LRP onset, but few have found effects on the time between LRP onset and RT (LRP-RT interval). The primary goal of this study was to produce an effect on the LRP-RT interval. We employed precuing, a manipulation likely to influence motor-programming processes at the end of the RT interval. Subjects performed a 4-alternative choice-RT task in which a signal prompted a button-press with the index or middle finger on the left or right hand. Precues preceded the signals and were either informative, reducing the set of response alternatives from four to two, or uninformative. Besides RT and LRP, we also measured electromyographic (EMG) activity and the P300 ERP component. RT, P300 latency, and the interval between the signal and LRP onset were all shorter with informative than uninformative precues, but the timing of EMG activity relative to RT remained the same. Most importantly, precuing affected the LRP-RT interval. Implications for bisecting RT with LRPs and the identity of processes affected by precuing are discussed.