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1.
The ability to allocate attention to emotional cues in the enviromnent is an important feature of adaptive self-regulation. Existing data suggest that physically abused children overattend to angry expressions, but the attentional mechanisms underlying such behavior are unknown. The authors tested 8-11-year-old physically abused children to determine whether they displayed specific information-processing problems in a selective attention paradigm using emotional faces as cues. Physically abused children demonstrated delayed disengagement when angry faces served as invalid cues. Abused children also demonstrated increased attentional benefits on valid angry trials. Results are discussed in terms of the influence of early adverse experience on children's selective attention to threat-related signals as a mechanism in the development of psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
Investigated whether the interaction between endogenous cueing and stimulus/response (S/R) would be obtained if attention was controlled exogenously, using 16 Ss. Central and peripheral cues were used to endogenously or exogenously direct the S's attention to the location at which an increase or decrease in the size of a peripheral object was most likely to occur. For each S, one size change was more likely to occur than the other, and the task was choice reaction time (RT; expansion/contraction). S/R probability (particular size change) interacted with cue condition (valid, neutral, and invalid) when the cues were central (endogenous), but the 2 variables were additive when the cues were peripheral (exogenous). Data suggest that controlled allocation of attention in response to a peripheral cue involves qualitatively different mechanisms from those associated with endogenous generation of an expectancy. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
BACKGROUND: We investigated whether schizophrenic subjects are impaired in non-routine behaviour because of the dysfunction of a general executive component labelled, in neuropsychological terms, the supervisory system. METHODS: A specific verbal sequencing test was designed for this purpose. Subjects had to perform sequential reasoning with verbal material. Each test sequence consisted of a series of words presented in jumbled order. The construction of some sequences had to be done using familiar routine associations (valid conditions). In contrast, some other sequences required the overriding selection of familiar routine associations, which were inappropriate within the general context of the task (invalid conditions). Twenty verbal sequences (10 valid-10 invalid) were administered. Thirty-seven DMS-IV schizophrenic patients and 21 normal volunteers matched for age and educational level were recruited. RESULTS: Compared to the control group the schizophrenic group was impaired in both valid and invalid conditions. The number of 'capture errors' specific to supervisory system failure was significantly higher in the schizophrenic group and only the schizophrenic patients had significantly fewer correct sequences in invalid conditions than in valid conditions. Poor performance in invalid conditions alone was observed only among the schizophrenic subjects without a general cognitive defect. CONCLUSIONS: These findings suggest that sequencing procedures requiring an executive input are impaired in schizophrenia.  相似文献   

4.
The study was based on the inverse relationship between the effect of attention on reaction time (RT) and the size of the area over which focal attention is allocated. Independent occurrence of this in 2 locations in the opposite hemifields would be evidence of attention splitting. In Exp 1, in which the 2 locations were denoted by empty boxes, there was an inverse relationship between size of the stimulated box and RT. Exp 2 replicated the finding with different stimulation conditions. In Exp 3, no relationship was found between RT and length of a cuing line. In Exp 4, in which attention was manipulated by central cues, there was an effect of box size on valid and neutral trials but not invalid trials. Observers could split focal attention and manipulate simultaneously 2 independent attentional foci on objects located in the opposite hemifields. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
Notes that RT in normal Ss has been shown to be linearly related to stimulus complexity, defined as the log of the number of equally probable stimuli to which a response may be made. Data from an earlier study of 40 short- and long-term paranoid and nonparanoid male schizophrenics and 10 male hospital employees were reanalyzed and compared with P. Venable's (see record 1959-10789-001) study of schizophrenic deficit. Although experimental procedures were dissimilar, both studies found that increased complexity did not result in schizophrenics having steeper regression slopes than normal Ss. Consideration of the position of the critical stimulus, however, clearly indicated that long-term, nonparanoid schizophrenics narrow attention to central cues when confronted by an increase in complexity. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Is brain pathology in schizophrenia topographically distinct? If so, are the putative regional changes unique to the disorder? To address these questions, 56 chronic schizophrenic Ss were compared with 16 psychiatric control Ss with mood disorders and with 31 healthy volunteers on multiple-volume measures of regional cerebral atrophy obtained with computed tomography. Generalized cortical and subcortical enlargement of spaces filled with cerebrospinal fluid sparing only the occipitoparietal cortex was found in the schizophrenic Ss compared with normal control Ss. Statistically significant differences in the extent of perisylvian atrophy were noted between schizophrenic Ss and patients with mood disorders: Schizophrenic Ss evidenced greater dilation of perisylvian fissures and sulci. The implications of the results for future research and for recent theories on the etiology of schizophrenia are discussed.  相似文献   

7.
Reaction times of schizophrenic and normal Ss were determined under instructions to respond as fast as possible to a buzzer signal. Half of the Ss were retested immediately under the same conditions, while the other half were shocked on the responding finger simultaneously with the buzzer. Schizophrenics' RTs improved significantly under shock conditions. Disturbances in schizophrenic RT are "partially accounted for by defective social motivation and… a biological deficit may be involved in the reactions of more chronic schizophrenics." 21 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
Shifts of visual attention elicited by spatial cues were examined for detection and letter-discrimination tasks in 90 normal adults ranging in age over each decade from the 20s to the 70s. Spatial cues were valid, invalid, or neutral in indicating probable target location and were presented either centrally at fixation or peripherally 6.7 degrees to the left or right of fixation. Stimulus-onset asynchrony (SOA) between cue and target was varied between 200, 500 and 2000 msec. Reaction time (RT) costs and benefits associated with spatial cueing did not vary with age for: (1) the detection task; (2) the letter-discrimination task with peripheral cues; and (3) the letter-discrimination task with central cues at a short (200 msec) SOA. RT costs and benefits increased with age only for SOAs greater than 200 msec with central cueing in the discrimination task. In general, the efficiency of cue-based shifts of visuospatial attention appears relatively resistant to the effects of adult age up to 79 years. When an age effect was found, RT costs and benefits increased steadily across all age decades, the correlation with age being 0.25 and 0.38 for the 500 and 2000 msec SOAs, respectively. The findings suggest a qualitative difference in the influence of normal adult aging and effects of dementia noted in previous studies; normal aging has only a weak influence on voluntary attention shifts, whereas dementia affects both voluntary and involuntary modes of attention shifting.  相似文献   

9.
Clinical studies show that schizophrenic and depressive subjects have problems with daily life activities, and neuropsychological studies tend to explain these problems in terms of a dysexecutive syndrome. Verbal fluency and sentence arrangement are tasks considered to focus on two aspects of the dysexecutive syndrome known as initiation and supervision processes, respectively. In this study, we assessed performance in these two tasks in schizophrenia and depression. Twenty-six schizophrenic subjects (chronic schizophrenia, DSM IV definition) were compared with 26 control subjects balanced for sex, age and educational level, and 16 depressive subjects (major depression episode, DSM IV) were compared with 11 similarly balanced control subjects. Switching and clustering scores were evaluated during a semantic fluency task as two components underlying the initiation and organization processes. Capture errors specific to failure of the supervisory system and differences between the number of correct responses in two conditions (valid/invalid) were evaluated as indexes of the supervision process in a sentence arrangement task. In the semantic fluency task, switching scores were significantly lower in the schizophrenic and depressive subjects than in their respective controls. In the sentence arrangement task, only the schizophrenic subjects made significantly more capture errors than their controls and had significantly fewer correct sequences in invalid conditions than in valid conditions. This study shows a dissociation between supervision and initiation processes in two different psychiatric populations. Initiation is impaired, but supervision is preserved in depression, whereas both initiation and supervision are impaired in schizophrenia.  相似文献   

10.
Previous research has demonstrated that spatial attention is "depth-aware": Reaction times (RT) are greater for shifts in depth and two-dimensional (2-D) space than in 2-D space alone. This experiment examined whether the ability to focus attention at a depth location is maintained with advanced age. Twelve younger and 12 older observers viewed stereoscopic displays in which one of four spatial locations was cued. Two of the locations were at a near depth location and two were at a far depth location. When the focus of visual attention was shifted to a new location in space (because of an invalid cue), the cost in RT for switching attention (measured as the difference between RT on valid cue and invalid cue trials) was greater when observers had to switch attention between different depth locations and different locations in 2-D space than for shifts in 2-D space alone. This effect was observed for both younger and older observers, suggesting that the ability to orient attention to a depth location is maintained with age.  相似文献   

11.
22 normals and 22 schizophrenics underwent differential conditioning of the GSR, using 8-sec tones of differing frequencies as the CSs, an 8-sec CS-UCS interval, and a UCS comprised of an RT task signaled by a low-intensity light. Both intertrial reports and postconditioning interviews were obtained. 12 Ss in the normal group verbalized the CS relations accurately, compared to 3 Ss in the schizophrenic group. The normal group showed significant GSR differentiation, though conditioning was limited to the group of accurately verbalizing Ss. No evidence for conditioning was obtained in the schizophrenic group. Normal Ss had faster RTs than schizophrenic Ss. The RT of accurately verbalizing normals was shorter than that of inaccurately verbalizing normals, and the degree of GSR differentiation was significantly correlated with RT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
Two models of visual orienting of attention are frequently described. Voluntary orienting is usually induced by central cues that direct subjects' attention to a given location in the visual space. Automatic orienting is provoked by presentation of peripheral cues. It is shown that automatic orienting induces greater attentional costs and benefits, and is less under a subject's control (Jonides 1981). Furthermore, it is not similarly affected by factors such as signal eccentricity (Umiltà et al. 1991). The present experiment was undertaken to investigate how sensitive automatic orienting produced by peripheral cues is to voluntary modulations of attention. In experiment 1, subjects facing situations daily in which attentional requirements are high, were compared to non-practiced ones. In experiment 2, other groups of practiced subjects facing high or low attentional-demanding situations were tested. In both experiments, subjects were asked to respond to signals, presented in rapid succession, in one of two possible locations in space, on each side of central fixation point. The cue signal automatically oriented attention to one of the two locations in which a first stimulus was presented with 100% probability; 100 ms after the first response (RT1), a second response signal (RT2) was delivered either in the same location (valid condition) or in the opposite location (invalid condition). Four cue probabilities were manipulated for this second stimulus: 100%/0%, 80%/20%, 50%/50%, and 20%/80%. Two eccentricities of 3 degrees and 6 degrees were tested. RT2 data demonstrated that (1) there was no eccentricity effect; (2) the higher the cue probability, the greater were the attentional costs; (3) the attentional effects were smaller in the practiced subjects who faced attention-demanding situations daily, than in the other groups. Put together, these data suggest that automatic orienting of attention can be modulated by voluntary attentional processes, according to cue probability. Furthermore, experienced subjects seem to be able to better distribute their attentional resources in space, with increased task requirements. The adoption of an optimal criterion might lead to the use of a cost minimizing strategy.  相似文献   

13.
Presents a visual–spatial approach to the study of attention dysfunction. The hypotheses of broadened and narrowed attention were tested by comparing peripheral visual discrimination of 10 acute schizophrenic and 11 chronic schizophrenic inpatients and 16 normal Ss (hospital staff) within 2 regions of the functional visual field. Pairs of visual stimuli were presented at 4 display angles. Measures of response accuracy, response latency, and latency of eye movement of peripheral stimuli were obtained. Results indicate that acute schizophrenics generally discriminated peripheral signals more accurately than chronic schizophrenics or normals. Normals discriminated signals more accurately than chronic schizophrenics. Results suggest the differential use of selective strategies. Limitations in the use of peripheral information among chronic schizophrenics implies a reduction in the amount of information transmitted in a selective act and a reduction in the economy of selective activities. In contrast to normals, acute schizophrenics utilized more efficient selective strategies over a greater spatial area, implying greater transmission of information within discrete selective acts. Results also indicate that schizophrenics initiated eye movements earlier than normals and that response latency was greater for acute schizophrenics than for normals. Results are interpreted as providing partial support for P. H. Venable's (1964) theory of input dysfunction. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
This research examined 2 components of visual orienting in medicated schizophrenia patients: the validity effect and the inhibition of return (IOR). In the 1st experiment, patients showed the expected asymmetry in orienting attention, that is, larger validity effect in the right visual field than in the left. However, this asymmetry was due to a deficit in facilitatory processes rather than a disengagement deficit. In addition, patients showed a deficit in IOR. In the 2nd experiment, a 2nd central cue for summoning attention, explicitly, back to the center was used. In this experiment, normal IOR in schizophrenia patients was found. Because it was shown that schizophrenia patients do not have a disengagement deficit, IOR possibly could not be observed because of the increased facilitation in that location. It was proposed that the abnormality in visual attention in schizophrenia is due to a deficit in inhibitory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Four classroom teachers rated the school behavior of 44 12–17 yr olds of schizophrenic parents and 70 Ss of normal parents as part of an ongoing high-risk study. The ratings were made by teachers using the Pupil Rating Form and the Hahnemann High School Behavior Rating Scale. Ss of schizophrenic parents showed greater interpersonal disharmony, less scholastic motivation, more emotional instability, and lower intelligence than the control Ss, but the difference in introversion was not significant. Two of the 4 Ss with 2 schizophrenic parents had extremely low ratings for scholastic motivation, harmony, emotional stability, and intelligence and a 3rd was rated extremely low on emotional stability, but none of them was extremely introverted. On the basis of the results and a preliminary examination of intermediate outcomes (early hospitalization or psychological treatment after the initial school assessments), it is concluded that disharmony, emotional instability, and low intelligence are the early markers for vulnerability to schizophrenia worthy of most attention. The surprising absence of introverted behavior among Ss of schizophrenic parents indicates that introversion—when it is observed—may best be construed not as a static typology of preschizophrenic character but as a dynamic phase in a process of coping and retreat that precedes schizophrenic breakdown, sometimes by many years. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
To investigate attentional bias to threatening information, the authors propose a new version of the spatial cueing paradigm in which the focus is on perceptual accuracy instead of response speed. In two experiments, healthy volunteers made unspeeded discriminations between three visual targets presented left or right. Each target was preceded by a visual cue (colored rectangle) at either the same (valid) or opposite (invalid) location. By means of differential classical conditioning with aversive white noise, a threat cue and a control cue were created. Analyses of error rates showed that cueing effects (lower proportion of errors in valid trials relative to invalid trials) were more pronounced in threat trials than in neutral trials. This threat-related bias was particularly because of threat cues reducing accuracy in invalid trials, indicating difficulty disengaging attention from threatening information. Engagement of attention was not affected by threat, as threat cues did not facilitate the processing of targets in valid trials. The findings are discussed in light of the strengths and limitations of spatial cueing tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
We examined sustained attention in 32 schizotypic and 43 normal control Ss from a large, randomly ascertained nonclinical university population. Schizotypy status was determined with the Perceptual Aberration Scale. Sustained attention was measured with the Continuous Performance Test-Identical Pairs. Schizotypic Ss displayed significantly poorer sustained-attention performance than did control Ss, as measured by d and overall hit rate. Although schizotypic Ss evidenced greater levels of anxiety and depression, sustained-attention performance was not significantly associated with these mental state factors. Our results provide evidence for a subtle sustained-attention deficit among schizotypes and are interpreted in light of previous attention research with actual schizophrenic patients as well as children at risk for schizophrenia. Utility of the psychometric high-risk strategy in psychopathology research is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Objective: While attentional functions are usually found to be impaired in schizophrenia, a review of the literature on the orienting of spatial attention in schizophrenia suggested that voluntary attentional orienting in response to a valid cue might be paradoxically enhanced. We tested this hypothesis with orienting tasks involving the cued detection of a laterally presented target stimulus. Method: Subjects were chronic schizophrenia patients (SZ) and matched healthy control subjects (HC). In Experiment 1 (15 SZ, 16 HC), cues were endogenous (arrows) and could be valid (100% predictive) or neutral with respect to the subsequent target position. In Experiment 2 (16 SZ, 16 HC), subjects performed a standard orienting task with unpredictive exogenous cues (brightening of the target boxes). Results: In Experiment 1, SZ showed a larger attentional facilitation effect on reaction time than HC. In Experiment 2, no clear sign of enhanced attentional facilitation was found in SZ. Conclusions: The voluntary, facilitatory shifting of spatial attention may be relatively enhanced in individuals with schizophrenia in comparison to healthy individuals. This effect bears resemblance to other relative enhancements of information processing in schizophrenia such as saccade speed and semantic priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Evaluated global attentional deficits as possible childhood markers of schizophrenia. Performance deviance was assessed across a continuous performance test, an attention span task, and the Digit Span subtest of the Wechsler Intelligence Scale for Children (WISC). 63 children of schizophrenic parents, 43 children of parents with affective disorders, and 100 children of normal parents were tested when the children were 7–12 yrs old. A subgroup of Ss at risk for schizophrenia displayed extreme global deviance across attentional measures. Only a small number of Ss at risk for affective disorders and normal comparison Ss showed similar extreme attentional deficits. The global attentional deficits measured at these early ages were related to behavioral disturbances (behavior was assessed in 3–6 mo intervals since 1971) in young adulthood for Ss at risk for schizophrenia, but not for Ss in the affective risk group or in the normal comparison group. It is concluded that global attentional deficits have considerable specificity for predicting behavioral problems thought to be precursors of schizophrenia or schizophrenia-related disorders. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
The startle reflex (SR) elicited by abrupt stimuli can be modified by attention to nonstartling stimuli that shortly precede the startle-eliciting stimulus. The present study of 15 recent-onset, relatively asymptomatic schizophrenic outpatients and 14 demographically matched normal control Ss demonstrated that attentional modulation of SR is impaired in schizophrenic patients. Specifically, the control group exhibited greater startle eye-blink modification following to-be-attended prestimuli than following to-be-ignored prestimuli, whereas the patients failed to show the attentional modulation effect. These results suggest traitlike attentional deficits in schizophrenia because the patients were relatively asymptomatic. The measurement of attentional modulation of SR may provide a nonverbal, reflexive, state-independent marker of the vulnerability to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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