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171.
172.
Country,sex, and parent occupational status: Moderators of the continuity of aggression from childhood to adulthood 下载免费PDF全文
173.
John Eric Steephen Sneha Kummetha Siva Charan Obbineni Raju Surampudi Bapi 《International journal of psychology》2021,56(3):378-386
Due to mood-congruency effects, we expect the emotion perceived on a face to be biased towards one's own mood. But the findings in the scant literature on such mood effects in normal healthy populations have not consistently and adequately supported this expectation. Employing effective mood manipulation techniques that ensured that the intended mood was sustained throughout the perception task, we explored mood-congruent intensity and recognition accuracy biases in emotion perception. Using realistic face stimuli with expressive cues of happiness and sadness, we demonstrated that happy, neutral and ambiguous expressions were perceived more positively in the positive than in the negative mood. The mood-congruency effect decreased with the degree of perceived negativity in the expression. Also, males were more affected by the mood-congruency effect in intensity perception than females. We suggest that the greater salience and better processing of negative stimuli and the superior cognitive ability of females in emotion perception are responsible for these observations. We found no evidence for mood-congruency effect in the recognition accuracy of emotions and suggest with supporting evidence that past reports of this effect may be attributed to response bias driven by mood. 相似文献
174.
Timothy J. Trull Eric Hillerbrand 《Journal of psychopathology and behavioral assessment》1990,12(4):285-297
Normative data for the Fear Questionnaire (Marks & Mathews, 1979), a popular self-report instrument measuring phobic concerns, were collected from both a community and a collegiate sample. The covariation and internal consistency of the blood-injury phobia (BI), social phobia (SO), and agoraphobia (AG) subscales were assessed in each sample, and the factor structure of the items from these three subscales was examined. Results indicated that, in general, community subjects reported more phobic concerns than did collegiate subjects, and females reported greater phobic concerns than did males. Results from confirmatory factor analyses suggest that the three factors of BI, SO, and AG did not emerge from either data set. Follow-up exploratory factor analyses did identify the general factors of blood-injury phobia and agoraphobia. Normative data from the present study are compared to those obtained previously, and directions for future research are provided. 相似文献
175.
Age-related enhancement of a protein synthesis-dependent late phase of LTP induced by low frequency paired-pulse stimulation in hippocampus 下载免费PDF全文
Protein synthesis-dependent late phase of LTP (L-LTP) is typically induced by repeated high-frequency stimulation (HFS). This form of L-LTP is reduced in the aged animal and is positively correlated with age-related memory loss. Here we report a novel form of protein synthesis-dependent late phase of LTP in the CA1 region of hippocampus induced by a brief 1-Hz paired-pulse stimulation (PP-1 Hz, 1 min). In contrast to L-LTP induced by HFS, the late phase of PP-1 Hz LTP does not exist in young adult animals. Rather, it emerges and becomes enhanced in an age-related way. Thus, in 1.5- to 2-mo-old mice, a brief PP-1 Hz stimulation induces only a short lasting LTP, decaying to baseline in about 90 min. By contrast, PP-1 Hz stimulation induces an enduring and protein synthesis dependent LTP in 12- to 18-mo-old mice. The PP-1 Hz-induced L-LTP is dependent on NMDA receptor activation, requires voltage-dependent calcium channels, and is modulated by dopamine D1/D5 receptors. Because memory ability declines with aging, the age-related enhancement of L-LTP induced by PP-1 Hz stimulation indicates that this form of L-LTP appears to be inversely correlated with memory ability. 相似文献
176.
Dishabituation in Aplysia can involve either reversal of habituation or superimposed sensitization 总被引:2,自引:0,他引:2 下载免费PDF全文
Dishabituation has been thought to be due either to reversal of the process of habituation or to a second process equivalent to sensitization superimposed on habituation. One way to address this question is by testing whether dishabituation and sensitization can be dissociated. Previous studies using this approach in Aplysia have come to different conclusions about the nature of dishabituation, perhaps because those studies differed in many respects, including (1) whether they also observed transient behavioral inhibition, and (2) whether they used test stimuli that activated the LE siphon sensory neurons or as yet unidentified sensory neurons. To attempt to resolve the apparent contradictions between the previous studies, we have explored the importance of these two factors by performing a parametric study of dishabituation and sensitization of gill withdrawal in a simplified preparation that does not exhibit transient behavioral inhibition, using two different test stimuli that are known to activate the LE (Touch) or unidentified (Not Touch) sensory neurons. We find that dishabituation and sensitization in this preparation have similar time courses and generally similar functions of shock intensity. However, under one condition, with the Not Touch stimulus 2.5 min after the shock, dishabituation has a reverse effect of shock intensity. Additional analyses suggest that dishabituation with the Not Touch stimulus 2.5 min after the shock is due to reversal of habituation, whereas 12.5 min after the shock, dishabituation is due to superimposed sensitization. These results thus suggest that dishabituation may involve either process in the same preparation, and begin to define the conditions that favor one or the other. 相似文献
177.
Dressler LG Juengst ET 《The American journal of bioethics : AJOB》2006,6(6):18-20; author reply W10-2
178.
We investigated the role of response selection in sequence learning in the serial reaction time (SRT) task, by manipulating stimulus-response compatibility. Under conditions in which other types of learning, like perceptual, response-based, and response-effect learning, were unaffected, sequence learning was better with an incompatible than with a compatible stimulus-response mapping. Stimulus discriminability, on the other hand, had no influence on the amount of sequence learning. This indicates that the compatibility effects cannot be accounted for by a different level of task difficulty. Relating our results to the dimensional overlap model (Kornblum, Hasbroucq, & Osman, 1990), which assumes that incompatible stimulus-response mappings require more controlled response selection than do compatible stimulus-response mapping, we suggest that sequence learning in the SRT task is particularly effective when response selection occurs in a controlled way. 相似文献
179.
The authors examined the prediction of occupational attainment by age 40 from contextual and personal variables assessed during childhood and adolescence in 2 participant samples: (a) the Columbia County Longitudinal Study, a study of 856 third graders in a semirural county in New York State that began in 1960, and (b) the Jyv?skyl? Longitudinal Study of Personality and Social Development, a study of 369 eight-year-olds in Jyv?skyl?, Finland, that began in 1968. Both samples were followed up during adolescence and early and middle adulthood. Structural modeling analyses revealed that in both countries, for both genders, children's age 8 cognitive-academic functioning and their parents' occupational status had independent positive long-term effects on the children's adult occupational attainment, even after other childhood and adolescent personal variables were controlled for. Further, childhood and adolescent aggressive behavior negatively affected educational status in early adulthood, which in turn predicted lower occupational status in middle adulthood. 相似文献
180.
Myoelectric (EMG) signals are used in assistive technology for prostheses, computer and domestic control. However, little is known about the capacity of controlling these signals. Specifically, it is unclear whether myocontrol, i.e., the control of myoelectric signals, obeys the same laws as motor control. Neurologically intact adult participants performed pointing tasks with EMG signals captured from the forehead or the hand in two modalities (sustained: stabilize the signal amplitude in the target; impulsion: produce an impulse and return to resting level). In the sustained modality, the time to reach the target (reach time) increased logarithmically with target amplitude, which is compatible with the predictions of Fitts' law. The rate of failure was not significantly affected by target amplitude. In the impulsion modality, the reach time and the rate of failure followed a bow-shaped pattern as a function of target amplitude. Stabilization time in the sustained modality followed a convex (bow-shaped) pattern for the forehead and a concave pattern for the hand. This was the only significant effect of electrode placement in this study. These findings suggest that myocontrol obeys laws that are distinct from those determining motor control, and that the muscular and intra-muscular synergies that produce EMG signals are specific of each pointing modality and target amplitude. 相似文献