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181.
Farah Martha J.; Péronnet Franck; Gonon Marie A.; Giard Marie H. 《Canadian Metallurgical Quarterly》1988,117(3):248
Systematic effects of imagery on visual signal detection performance have been used to argue that imagery and the perceptual processing of stimuli interact at some common locus of activity (Farah, 1985). However, such a result is neutral with respect to the question of whether the interaction occurs during modality-specific visual processing of the stimulus. If imagery affects stimulus processing at early, modality-specific stages of stimulus representation, this implies that the shared stimulus representations are visual, whereas if imagery affects stimulus processing only at later, amodal stages of stimulus representation, this implies that imagery involves more abstract, postvisual stimulus representations. To distinguish between these 2 possibilities, we repeated the earlier imagery-perception interaction experiment while recording event-related potentials (ERPs) to stimuli from 16 scalp electrodes. By observing the time course and scalp distribution of the effect of imagery on the ERP to stimuli, we can put constraints on the locus of the shared representations for imagery and perception. An effect of imagery was seen within 200 ms following stimulus presentation, at the latency of the 1st negative component of the visual ERP, localized at the occipital and posterior temporal regions of the scalp, that is, directly over visual cortex. This finding supports the claim that mental images interact with percepts in the visual system proper and hence that mental images are themselves visual representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
182.
Replies to comments by J. W. Fagen (see record 1994-08950-001) on the article by J. L. Gewirtz and M. Peláez-Nogueras (see record 1993-12989-001), which concerned reinforcement as a central principle of behavior change in infants. Gewirtz and Peláez-Nogueras state that they did not claim that all behavior is learned through operant reinforcement contingencies. Further, they question the necessity of moving beyond basic reinforcement and derivative principles to the realm of intrapsychic concepts such as the "violation of contingency expectancy" to explain behavior changes resulting from operant learning procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
183.
A common practice in operational Machine Translation (MT) and Natural Language Processing (NLP) systems is to assume that a verb has a fixed number of senses and rely on a precompiled lexicon to achieve large coverage. This paper demonstrates that this assumption is too weak to cope with the similar problems of lexical divergences between languages and unexpected uses of words that give rise to cases outside of the pre-compiled lexicon coverage. We first examine the lexical divergences between English verbs and Chinese verbs. We then focus on a specific lexical selection problem—translating Englishchange-of-state verbs into Chinese verb compounds. We show that an accurate translation depends not only on information about the participants, but also on contextual information. Therefore, selectional restrictions on verb arguments lack the necessary power for accurate lexical selection. Second, we examine verb representation theories and practices in MT systems and show that under the fixed sense assumption, the existing representation schemes are not adequate for handling these lexical divergences and extending existing verb senses to unexpected usages. We then propose a method of verb representation based on conceptual lattices which allows the similarities among different verbs in different languages to be quantitatively measured. A prototype system UNICON implements this theory and performs more accurate MT lexical selection for our chosen set of verbs. An additional lexical module for UNICON is also provided that handles sense extension. 相似文献
184.
185.
Burton Martha W.; Baum Shari R.; Blumstein Sheila E. 《Canadian Metallurgical Quarterly》1989,15(3):567
This study examines the extent to which acoustic parameters contribute to lexical effects on the phonetic categorization of speech. Experiment 1 was designed to replicate previous findings. Two test continua were created varying in voice onset time. Results of both identification and reaction time (RT) range data showed an effect of lexical status at the phonetic boundary, but only in the slowest RT ranges, suggesting that lexical effects on phonetic categorization are postperceptual. Experiment 2 explored whether the lexical effect would emerge when the stimulus continua more nearly approximated the parameter values of natural speech. Both identification and RT range data indicated that the lexical effect disappeared. These results suggest that without attention to the acoustic structure of the stimuli, the role of top–down processing in phonetic categorization may be overemphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
186.
Paxton Jessica L.; Barch Deanna M.; Storandt Martha; Braver Todd S. 《Canadian Metallurgical Quarterly》2006,21(3):499
Age-related cognitive differences may be due, in part, to difficulties using task-relevant context in a proactive manner. Two studies evaluated different methods for increasing older adults' use of context in the AX-Continuous Performance Task (H. E. Rosvold, A. F. Mirsky, I. Sarason, E. D. Bransome, & L. H. Beck, 1956), which evaluates components of context processing. The results suggest that (a) age differences in the use of context are not due to reduced access to cue information, (b) directed strategy training made older adults' context processing performance more like that of young adults, and (c) similar performance changes could be observed with less directed instruction and extended practice. These results suggest that age-related differences in context processing can be ameliorated by directed strategy training or extended practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
187.
Berry David T. R.; Wetter Martha W.; Baer Ruth A.; Larsen Lene; Clark Cynthia; Monroe Keith 《Canadian Metallurgical Quarterly》1992,4(3):340
Investigated the validity of F, back F, and variable response inconsistency indices of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) for detection of self-reported partially random responding in several samples, including college students, community volunteers, and job applicants. Substantial numbers of Ss admitted to providing some random responses, with 29–60% of the various samples acknowledging an average of 12–38 random responses in their MMPI-2 answers. For all groups, with the expected exception of job applicants, the appropriate MMPI-2 validity indices were reliably and positively correlated with self-estimates of random responses. Available data suggested that random responding occurred most commonly toward the end of the test, although significant numbers indicated that they had scattered their random responses throughout the test. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
188.
Davies Ruth; Lacks Patricia; Storandt Martha; Bertelson Amy D. 《Canadian Metallurgical Quarterly》1986,1(3):233
Administered countercontrol behavioral therapy for sleep-maintenance insomnia to 34 insomniacs (aged 35–78 yrs) in small groups. 22 Ss received immediate and 12 received delayed treatment. Three self-report measures of sleep disruption were collected on daily sleep diaries at baseline, termination of treatment, 1-mo follow-up, and 12-mo follow-up. Although amount of time awake at night was correlated with age, response to treatment was not. Even though older Ss experienced more time awake after sleep onset prior to treatment, they were able to profit from therapy as well as the younger insomniacs. Countercontrol therapy reduced the sleep complaint for the total group by about 30% at the end of treatment, with gradual improvement continuing through a 4-wk follow-up. It is suggested, however, that sleep-maintenance insomnia may be more difficult to treat than sleep-onset problems. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
189.
Kihlstrom John F.; Glisky Martha L.; Angiulo Michael J. 《Canadian Metallurgical Quarterly》1994,103(1):117
Although dissociative disorders are relatively rare, dissociative experiences are rather common in everyday life. Dissociative tendencies appear to be modestly related to other dimensions of personality, such as hypnotizability, absorption, fantasy proneness, and some facets of openness to experience. These dispositional variables may constitute diatheses, or risk factors, for dissociative psychopathology, but more complex models relating personality to psychopathology may be more appropriate. The dissociative disorders raise fundamental questions about the nature of self and identity and the role of consciousness and autobiographical memory in the continuity of personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
190.