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71.
Aged rats with extensive prior training on the radial maze retain the capacity for accurate spatial working memory (WM) for at least 3 months without practice. To investigate the temporal limits of this influence of prior experience we compared the reacquisition of spatial WM by a group of experienced 21.5-month-old rats to the original acquisition by naive 3-month-old rats. The aged rats had received 225 radial maze tests between 3 and 11 months of age. Despite 10 months without practice the old rats rapidly reacquired critical performance. Their reacquisition was markedly superior to original learning by the young rats, even when delays as long as 5 h were imposed between the rats' fourth and fifth choices during the daily tests in the eight-arm maze. Additional tests showed that neither young nor old rats employed a response strategy to maintain accurate spatial WM performance. Experience clearly confers long-lived protection against the otherwise deleterious effects of aging on spatial WM, but the mechanism by which this influence arises is unknown.  相似文献   
72.
The ability to think of a previously studied item has often been shown to be impaired when, in one way or another, the extraitem context is changed from study to test. In a series of five experiments, such impairment is induced in a somewhat different way. A fragment (e.g. r-i--rop) of a just-studied word (raindrop) is shown to be less readily completed if it is presented bit by bit (r------p, r----r-p, r-i--r-p, r-i--rop) rather than all at once (Experiments 1, 3, 4, and 5). No such effect is found if the word has not been studied beforehand (Experiments 2, 3, 4, and 5). This pattern of results occurs even when fragments of studied and nonstudied words occur in the same test and under conditions in which subjects cannot tell whether a given fragment is of a studied or nonstudied word (Experiments 4 and 5). In addition, for words that have been studied beforehand, the impairment is shown to increase systematically with the number of steps involved in the presentation of the word fragment (Experiment 3) and also to persist when the time allowed for completion of the final version of the fragment is increased from 4 s to a full minute (Experiment 5).  相似文献   
73.
The social adjustment of the adolescent offspring of parents with bipolar affective disorder (n=41) was compared to that of the offspring of parents with nonaffective psychiatric disorders (n=22) and the offspring of normal controls (n=26). In addition, the relationship between social adjustment and cyclothymia in offspring was determined. Social adjustment was assessed using the Life Activities Inventory, a new measure developed to assess social functioning in adolescents and young adults. Cyclothymia was assessed with the General Behavior Inventory. As a group, the offspring of bipolar parents did not differ significantly from either control group on social adjustment. However, the cyclothymic offspring of bipolar parents exhibited significantly poorer social adjustment than the noncyclothymic offspring of bipolars and the offspring of psychiatric and normal controls. These findings suggest that poor social functioning in the adolescent offspring of parents with bipolar illness may be associated with the early manifestations of affective disorder. In addition, these data indicate that despite its subsyndromal intensity, cyclothymia can result in significant social impairment.This study was supported in part by National Institute of Mental Health (NIMH) Research Grant MH-39782 to Daniel N. Klein and NIMH Grants MH-33083 and MH-37195 to Richard A. Depue.  相似文献   
74.
There has been interest in recent years in the relationship between marital distress and psychopathology. It has been rare, however, for investigators to follow patients after their release from the hospital and observe the course of their marital relationships. The present study included patients meeting criteria for three DSM III DISORDERS (MAjor depressive, bipolar, and schizophrenic) and a normal control sample, all of whom are participants in an ongoing longitudinal study of children at risk for psychopathology (Stony Brook High-Risk Project; Weintraub & Neale, 1984). Marital Adjustment Test (MAT; Locke & Wallace, 1959) scores were collected on patients at entry into the project (Phase I) and at a three year follow-up (Phase II). Course of marriage was defined as negative if the couple's marital adjustment was rated as poor at Phase II or resulted in divorce or separation at Phase II. It was found that only the depressed group differed from the normal group in having significantly worse course of marital relationship; 84% of the depressive couples showed a “negative” course of marital change over time. However, all three patient groups had significantly higher rates of divorce by Phase II. MAT scores at Phase I successfully predicted course of marital relationship for all diagnostic groups. Implications for aftercare of psychiatric inpatients are discussed.  相似文献   
75.
76.
Two cognitive approaches, introduced by Schachter and Singer (1962) and by Valins (1966), have dominated the experimental study of emotion attributions. However, subsequent results using these approaches have not appeared to be very consistent, and this view is not consistent with more physiologically oriented theory. Research significant in the development of theory from these approaches was examined. Inconsistent findings using the Schachter and Singer paradigm were attributed to the difficulty of producting completely ambiguous physiological cues. The existence of active search in determining the cause of arousal was established and found central to production of Valins's false feedback effect. Postulated mediation by self-persuasion was found to provide the best fit to the existing data. The generality of these studies was described in terms of a more comprehensive theory based on the finding that the relative ambiguity of situational and physiological cues seems to provide the fundamental control over the emotion attribution process. This synthesis eliminates the deficiencies in previous hypotheses by more completely encompassing potential cue combinations.  相似文献   
77.
The purpose of this study was to clarify contradictory findings concerning the social status of aggressive youngsters. This was undertaken by dividing kindergarten boys into either Aggressive [A] or Aggressive/Withdrawn [A/W] groups, as proposed by Ledingham [1981]. Both groups were found to be high on peer-nominated rejection, but the A group was also high on peer-nominated popularity while the A/W group was low. Similarly, both groups were observed to be high in negative peer interactions, but the A group was also high in positive interactions. It was noted that valuable information regarding the social status and social behavior of aggressive youngsters would be lost if such subgrouping is not undertaken. The relationship between Ledingham's categorizations and others reported in the literature was discussed.This research was supported in part by NIH grant No. 32992 to the first author.  相似文献   
78.
Summary Previous investigations of the global precedence hypothesis (Navon, 1977) have utilized compound letter stimuli. In these stimuli there is no predictive relationship between the global and local levels. Pictorial stimuli, however, contain mutually predictable global and local levels. This study investigated the global precedence hypothesis with pictorial stimuli using a Stroop-like interference task similar to that used by Navon. Subjects were required to respond either to the global (e.g., beach or farm) or local (e.g., boat or tractor) level of a scene. The display size and consistency of the global and local levels were varied. Response latencies supported global precedence for small scenes (4°) but local precedence for large scenes (16°). The results are interpreted by a model in which the priority of processing is determined by a critical spatial frequency sampling bandwidth.Portions of this research were presented at the meeting of the Psychonomic Society, Minneapolis, November, 1982. The authors with to express their sincere appreciation to Tom Petros for his assistance in data analysis. Requests for reprints should be addressed to James R. Antes, Department of Psychology, University of North Dakota, Grand Forks, ND 58202.  相似文献   
79.
The self-injurious forehead-gouging behavior that had resulted in blindness for a profoundly retarded 27-yr-old male was successfully treated using a combination of differential reinforcement of incompatible behavior during unstructured situations and prevention of escape during compliance situations. After self-injurious behavior was reduced to a low frequency, a reduction of his daily dose of chloral hydrate was accompanied by a large increase in self-injury, but the behavior gradually returned to its previous low level. A large increase in self-injury also occurred following transfer to another living unit, but the behavior again decreased to a low frequency. Treatment gains were maintained following transfer to another residential facility with follow-up observations occurring at 1, 2, 8, 15, 22, 27 and 35 months. The multiple determination of self-injurious behavior in this one S highlights the behavioral complexity of some of these behaviors.  相似文献   
80.
A sentence often contains two components: a topic, which refers to a nonlinguistic object whose existence is presupposed; and a comment, which asserts some thought about this object. In addition, a sentence will often repeat (or refer back to) information that was expressed earlier in a text or conversation. The purpose of this article is to propose a single theoretical framework to describe the mechanisms that relate a sentence to its nonlinguistic environment as well as those that relate a sentence to its linguistic context. The theory developed in this article suggests that sentences can strongly influence the representation of visible nonlinguistic events and that this representation is sensitive to the distinction between presupposed and asserted information. To evaluate this theory, a sentence-picture verification priming task was developed. In this task, subjects were presented with pairs of sentence-picture displays, and were asked to verify whether or not the sentence in each display correctly applied to an accompanying picture. The relationship between pairs of sentence-picture displays was varied systematically. Across five experiments, three hypotheses were supported: (a) The processes which evaluate presupposed information and the processes which evaluate asserted information are differentially affected by nonlinguistic factors, (b) only those aspects of the picture which are referred to by the sentence are encoded for future use, and (c) coherence between successive sentences is in part a function of the referential continuity of the presupposed information.  相似文献   
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