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821.
Cohen MR Meissner GW Schafer RJ Raymond JL 《Learning & memory (Cold Spring Harbor, N.Y.)》2004,11(5):559-565
Motor learning in the vestibulo-ocular reflex (VOR) and eyeblink conditioning use similar neural circuitry, and they may use similar cellular plasticity mechanisms. Classically conditioned eyeblink responses undergo extinction after prolonged exposure to the conditioned stimulus in the absence of the unconditioned stimulus. We investigated the possibility that a process similar to extinction may reverse learned changes in the VOR. We induced a learned alteration of the VOR response in rhesus monkeys using magnifying or miniaturizing goggles, which caused head movements to be accompanied by visual image motion. After learning, head movements in the absence of visual stimulation caused a loss of the learned eye movement response. When the learned gain was low, this reversal of learning occurred only when head movements were delivered, and not when the head was held stationary in the absence of visual input, suggesting that this reversal is mediated by an active, extinction-like process. 相似文献
822.
McNulty, Harkness, Ben-Porath and Williams recently developed Personality Psychopathology Five (PSY-5) scales for the Minnesota Multiphasic Personality Inventory-A (MMPI-A). This study examined these new scales in a sample of 545 adolescents receiving inpatient psychiatric treatment. Item-level principal components analyses were employed to determine the internal structure of each PSY-5 scale and to aid in the creation of facet subscales for each PSY-5 scale. Results suggest that the MMPI-A PSY-5 scales display adequate internal consistency and our findings generally replicate the original work of McNulty et al. but also extend this work by showing that several of the PSY-5 scales may also be subdivided into meaningful lower level dimensions. These facet subscales for each of the MMPI-A PSY-5 scales are offered for further study. 相似文献
823.
There is a high prevalence of psychological disorders among adolescents in detention facilities. The need for a simple, effective screening tool led to the development of the Massachusetts Youth Screening Instrument (MAYSI) and its successor, the MAYSI-2. This study evaluated the MAYSI-2 psychometric properties based on the records of 704 youths evaluated at intake to detention facilities. In addition to factor structure, the study evaluated test-retest reliability and concurrent external validity. Results were generally encouraging in terms of the use of MAYSI-2 in detention facilities, and directions for future research are discussed. 相似文献
824.
The lexically based Five-Factor Personality Inventory (FFPI) was correlated with the factors and facets of the Revised NEO Personality Inventory (NEO-PI-R) in Belgian (N = 265), American (N = 116), and Hungarian (N = 320) samples. Results were similar across the three cultures. Analysis of orthogonalized FFPI factors showed that three of them--emotional stability, extraversion, and agreeableness--showed a direct correspondence to their NEO-PI-R counterparts. Autonomy, however, was not clearly related to openness, and facet analysis suggested that it might be interpreted as a dominance factor Better matches to NEO-PI-R conscientiousness and openness could be obtained by using vectors rotated 30 degrees from the FFPI positions. Raw scale scores showed similar results. Researchers should not assume that all measures of the Five-Factor Model are qualitatively similar 相似文献
825.
The MMPI-2 Superlative (S) scale was developed by Butcher and Han (1995) to assess individuals' tendencies to present themselves in an unrealistically positive light. The current study examined the performance of the L, K, and S scales in accurately distinguishing the MMPI-2 profiles of 379 psychiatric inpatients who produced one or more elevations on the basic scale profiles, from 82 psychiatric inpatients who produced no clinical range elevation on any of the eight basic clinical scales (excluding scales 5 and 0). The findings from the present study indicate that the S scale appears to be effective in the identification of defensiveness among psychiatric inpatients, with mean effect sizes in the moderate to large range. The optimal T-score cutoff for identifying defensive responders was 70 for both men and women. Further, results of hierarchical regression analyses showed that the S scale added incrementally to the prediction levels achieved by the optimal combination of the L and K scales. 相似文献
826.
The role of the hippocampus in object recognition memory processes is unclear in the current literature. Conflicting results have been found in lesion studies of both primates and rodents. Procedural differences between studies, such as retention interval, may explain these discrepancies. In the present study, acute lidocaine administration was used to temporarily inactivate the hippocampus prior to training in the spontaneous object recognition task. Male C57BL/6J mice were administered bilateral lidocaine (4%, 0.5 microl/side) or aCSF (0.5 microl/side) directly into the CA1 region of the dorsal hippocampus 5 min prior to sample object training, and object recognition memory was tested after a short ( 5 min) or long (24 h) retention interval. There was no effect of intra-hippocampal lidocaine on the time needed for mice to accumulate sample object exploration, suggesting that inactivation of the hippocampus did not affect sample session activity or the motivation to explore objects. Lidocaine-treated mice exhibited impaired object recognition memory, measured as reduced novel object preference, after a 24 h but not a 5 min retention interval. These data support a delay-dependent role for the hippocampus in object recognition memory, an effect consistent with the results of hippocampal lesion studies conducted in rats. However, these data are also consistent with the view that the hippocampus is involved in object recognition memory regardless of retention interval, and that object recognition processes of parahippocampal structures (e.g., perirhinal cortex) are sufficient to support object recognition memory over short retention intervals. 相似文献
827.
828.
The mainstay of treatment for chronic posttraumatic stress disorder (PTSD) is a combination of psychotherapy and medication treatments. The first-line medications for PTSD are antidepressants, with two selective serotonin reuptake inhibitors (sertraline and paroxetine) currently Food and Drug Administration-indicated for PTSD. However, many patients do not have an adequate response to antidepressants, therefore, combinations with other antidepressants or with other classes of psychotropic medication are often utilized to enhance the therapeutic response. Other agents that have been used include mood stabilizers, anti-adrenergics, anxiolytics, and atypical antipsychotics. The heterogeneity of symptom clusters in PTSD as well as the complex psychiatric comorbidities (eg, with depression or substance abuse) further support the notion that combinations of medications may be needed. To date, there is a paucity of data to support specific strategies for augmenting antidepressants in PTSD. This review will address representative existing studies and discuss several potential pharmacologic strategies for patients suffering from treatment-refractory PTSD. 相似文献
829.
Catalano GD 《Science and engineering ethics》2004,10(2):409-415
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional
issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought
to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within
which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving
the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple
workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed
using Kirkpatrick’s model for evaluating training programs.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献
830.
Yago E Duarte A Wong T Barceló F Knight RT 《Cognitive, affective & behavioral neuroscience》2004,4(4):609-617
Single-unit, event-related potential (ERP), and neuroimaging studies have implicated the prefrontal cortex (PFC) in top-down
control of attention and working memory. We conducted an experiment in patients with unilateral PFC damage (n=8) to assess the temporal kinetics of PFC-extrastriate interactions during visual attention. Subjects alternated attention
between the left and the right hemifields in successive runs while they detected target stimuli embedded in streams of repetitive
task-irrelevant stimuli (standards). The design enabled us to examine tonic (spatial selection) and phasic (feature selection)
PFC-extrastriate interactions. PFC damage impaired performance in the visual field contralateral to lesions, as manifested
by both larger reaction times and error rates. Assessment of the extrastriate P1 ERP revealed that the PFC exerts a tonic
(spatial selection) excitatory input to the ipsilateral extrastriate cortex as early as 100 msec post stimulus delivery. The
PFC exerts a second phasic (feature selection) excitatory extrastriate modulation from 180 to 300 msec, as evidenced by reductions
in selection negativity after damage. Finally, reductions of the N2 ERP to target stimuli supports the notion that the PFC
exerts a third phasic (target selection) signal necessary for successful template matching during postselection analysis of
target features. The results provide electrophysiological evidence of three distinct tonic and phasic PFC inputs to the extrastriate
cortex in the initial few hundred milliseconds of stimulus processing. Damage to this network appears to underlie the pervasive
deficits in attention observed in patients with prefrontal lesions. 相似文献