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981.
One hundred and thirty-three college students responded to percentage definitions of “good,” “minimal,” and “no” eye contact. They also judged their perceptions of a speaker with “little or no eye contact” on a semantic differential scale containing 60 polarized adjective pairs regarding personality traits. The majority of the student respondents defined an individual with “good” eye contact as looking at his/her audience/listener 90–100% of the time. This is a more stringent definition than other literature has indicated. Furthermore, speakers with little or no eye contact were judged less favorably on 70% of the items, which indicates that low eye contact adversely affects perceptions of a speaker's personality. Therefore, stutterers need to be made aware of the importance of and determinants of effective eye contact in communication. Also, the development of effective eye contact needs to be incorporated as a major goal in stuttering therapy.  相似文献   
982.
Stress in time     
The goals of this research were to determine whether speakers adjust the stress patterns of words within sentences to create an alternation between strong and weak beats and to explore whether this rhythmic alternation contributes to the characteristics stress differences between two major lexical categories of English. Two experiments suggested that speakers do alter lexical stress in accordance with rhythmic biases. When speakers produced disyllabic pseudowords in sentence contexts, they were more likely to place stress on the first syllable when the pseudoword was preceded by a weak stress and followed by a strong one than when the strong stress preceded and the weak followed. This occurred both when the pseudowords served as nouns and when they served as verbs. Text analyses further revealed that weakly stressed elements precede nouns more often than verbs, whereas such elements follow verbs more often than nouns. Thus, disyllabic nouns are more likely than disyllabic verbs to occupy contexts biased toward trochaic rhythm, a finding consistent with leftward dominant stress in disyllabic English nouns. The history of stress changes in English nouns and verbs also conforms with the view that rhythmic context may have contributed to the evolution of stress differences. Together, the findings suggest that the citation stress patterns of words may to some degree reflect adaptations of lexical knowledge to conditions of language performance.  相似文献   
983.
Multiunit activity (MUA) was recorded chronically in the hippocampus (CA3) and the medial geniculate body (mMG) during habituation to a tone followed by conditioning (tone paired with footshock) or pseudoconditioning (tone/footshock unpaired) in rats previously trained in a lever-pressing for food task (VI 60). In the conditioned group pairing tones with footshocks rapidly induced an increase in the initial CS-evoked response in the mMG, followed by the emergence of a hippocampal response and a marked conditioned suppression of lever-pressing to the tone. In contrast, in the pseudoconditioned group, the stimulus induced only transient cellular changes in the hippocampus and in the mMG, while no behavioral suppression to the tone could be seen. Moreover, presentations of the CS 45 days later induced multiunit and behavioral responses in both structures, only in the conditioned group. These results are used for discussion of the role of learning-induced changes in the sensory structure (mMG) as compared with changes in an associative structure (hippocampus), during acquisition and retention of a conditioned response.  相似文献   
984.
Hormones and peptides involved in the response of an organism to stress play a modulating role in learning and memory processes. We studied whether psychoneurogenic stressors such as sound stimulation or novelty influence retention of an inhibitory avoidance response. An impairing effect on retention was observed when these stressors were applied shortly after the acquisition trial, but not after a 3-h delay. However, sound stimulation and novelty applied shortly before the retention test may facilitate retention behavior. It is suggested that the effect of psychoneurogenic stressors on retention behavior may be linked to influences on consolidation and retrieval processes mediated through the neurohumoral response of the organism to stress.  相似文献   
985.
For 3 consecutive days cockroaches (Periplaneta americana) were exposed to either escapable, inescapable, or no shock in an escape task. Twenty-four hours later they were tested in a shuttlebox escape task. There were reliable differences between escapable and inescapable animals and between inescapable and control animals in both escape latencies and the number of failures to escape.  相似文献   
986.
In a previous study (H. J. Bischof & K. Herrmann (1986), Behavioral Brain Research, 21, 215-221) we demonstrated that four forebrain areas of the zebra finch male are activated in situations which arouse the animal, for example when the birds are chased around the cage or when they are exposed to a female. These areas, the hyperstriatum accessorium-dorsale (HAD), a part of the medial neo-hyperstriatum (MNH), the lateral neo-hyperstriatum (LNH), and a portion of the caudal archi-neostriatum (ANC), show enhanced 2-[14C]deoxyglucose (2-DG) uptake according to the experimental situation. On the basis of these experiments, we examined whether the activation of the areas is correlated with motor activity and is influenced by different isolation times prior to a 2-DG experiment, where courtship of the male birds is elicited by exposing them to a female zebra finch. For this purpose, we isolated male zebra finches for 1 day, 1 week, or 8 weeks, respectively, before we injected the 2-DG and exposed the birds to a female. During the experiment, besides other activities, the number of song motifs performed by the bird and the frequency of changing perches was recorded. Our experiments demonstrate that there is a weak negative correlation between motor activity and 2-DG uptake, and a positive correlation between isolation time and 2-DG uptake. We suggest that long isolation blocks courtship behavior by some unknown mechanisms, and that the "internal drive" of the animal, which possibly corresponds with the activity of the four forebrain areas, is enhanced by isolation and by the fact that the birds do not perform the consummatory behavior. Our results also demonstrate that the 2-DG method can show up small differences in the internal state of an animal, which cannot easily be detected by behavioral measurements.  相似文献   
987.
Previously we (Bruno & Cutting, 1988) explored the perception of spatial relations among objects laid out in a computer-generated environment. In his commentary on our article, Massaro (1988) raised several issues. The most important is from his reanalysis, which indicated that--because of a subadditive trend in the results--additive and multiplicative strategies fit our data in Experiment 1 about equally well. In reply, we performed a different analysis. Results corroborate subadditivity--and hence multiplicative information combination--in Experiment 1 but provide no evidence for it in Experiments 2 and 3. On the whole, then, the results still support additivity more strongly than any other combination rule and thus support our notion of minimodularity.  相似文献   
988.
Ceci and Liker (1986b) presented data that they contended shows two things: (a) Handicapping harness races is a cognitively complex undertaking that can be captured by a multiple regression model, and (b) neither overall skill at handicapping nor the complexity of the mental model used is related to standard measures of intelligence. The first contention is not at issue. But the second contention, that handicapping performance is unrelated to IQ, is not supported by the data presented; in fact, the opposite conclusion seems more likely. The purpose of this comment is to point out errors frequently made in individual-differences research concerning population definition, sample selection, dependent and independent variable reliability and validity and interpretation of results.  相似文献   
989.
Pigeons in a matching-to-sample experiment received (a) element samples (one of two colors or vertical or horizontal white lines), (b) separated compound samples (a color and a line element presented together), and (c) unified compound samples (vertical or horizontal colored lines). In Phase I, test stimuli were the two elements from one dimension; the dimension tested varied randomly when the sample was a compound. Element samples were matched better than unified samples, which were matched better than separated samples. In Phase II, two samples preceded the tests. On EC trials, the first sample (S1) was an element, and the second sample (S2) was a compound; on CE trials this order was reversed. One element of the compound sample was always the one appearing as the element sample on that trial (e.g., S1 = red, S2 = red-vertical). This element also served as the correct test alternative (e.g., test = red+ vs. green) except on probe trials when the correct test was the other element appearing in the compound (e.g., test = vertical+ vs. horizontal). Accuracy varied as a function of sample sequence when the compound was separated (EC greater than CE on nonprobe trials and CE greater than EC on prove trials). This pattern was not observed when the compound was unified. The data suggest that the element in EC trials served as a cue that increased processing of the cued dimension and decreased processing of the noncued dimension of separated compounds. However, both dimensions of unified compounds seem to have been processed regardless of cuing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
990.
Fragile X speech phonology in Finnish   总被引:1,自引:0,他引:1  
Fragile X syndrome is a recently discovered relatively common syndrome linked with an anomaly of the X chromosome and causing handicaps of cognitive development especially in males. In the present phonological analysis we will discuss the sound patterns of two Finnish fragile X speakers, a five (borderline intelligence)- and an eight (mildly mentally retarded)-year-old boy. The fragile X syndrome is not necessarily linked with any anomalies of speech organs. The subjects could produce all Finnish speech sounds in isolated test words. However, in the present samples of connected speech they exhibited general dysphonology. What is noteworthy is that their phonological error patterns resembled each other to a great extent. Among the common features were the tendencies to substitute and omit phonemes. As for vowels, our results showed about one-half of the errors to be omissions. Labiality and quantity oppositions were quite resistant to substitution. Most substitution errors of place of consonants occurred in dentals. As for the feature of manner, /r/ and /s/ were the phonemes most prone for substitution. A tendency toward spirantization or /h/ sation was common for both patients. The number of additions was clearly lower than has been reported for English-speaking developmentally dyspraxic children and also for Finnish Broca's aphasics. The speech problems of our patients seemed to indicate higher level motor encoding problems of linguistic information rather than peripheral articulatory deficits.  相似文献   
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