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The discriminability of line segments in a number of different geometric forms was examined. The procedure used was to have one of the lines within a given form drawn thinner than the other lines. The location of the thin line varied randomly within the form, and subjects were required to detect its location. Three observations were made. First, outer line elements were discriminated more accurately than inner line elements. Second, the outer line advantage appeared to reflect an attentional strategy: By presenting inner and outer lines independently, and informing subjects in advance as to whether target lines would be in the inner or outer area of the form, the outer line advantage could be eliminated. Third, consonant with a global attentional strategy, and in opposition to any retinally tied, peripheral-to-central scanning process, an outer-line advantage was evident regardless of whether the fixation point was positioned within or outside the forms, or whether outer lines were more peripheral than inner lines.  相似文献   
3.
Sets of words can be grouped in terms of their denotation (cold and warm both refer literally to temperature) or in terms of their connotation (cold and warm connote remoteness and intimacy, respectively). To assess whether these two facets of meaning are dissociable, unilaterally left- and right-hemisphere-damaged patients were presented with word triads and asked to group together the two words that were closest in meaning. Right-hemisphere-damaged patients showed a preserved sensitivity to denotation, and a selective insensitivity to connotative facets of meanings. In contrast, left-hemisphere-damaged patients exhibited a preserved sensitivity to connotation as well as a selective insensitivity to denotative aspects of meanings. Inasmuch as normal control subjects displayed a flexible sensitivity to both denotative and connotative aspects of meaning, the results suggest that unilateral brain damage selectively curtails use of one or the other major aspect of word meaning.  相似文献   
4.
In this study, we evaluated several components of a pedometer-based intervention with children in an elementary-school-aged classroom, across 24-h sessions. The intervention included combinations of self-monitoring, goal setting, feedback, and reinforcement, and data were analyzed at both the classroom level (i.e., average daily step totals) and the individual level (i.e., daily step totals), across phases. The highest levels of physical activity were observed when components of self-monitoring, public posting, goal setting, and feedback with reward were applied concurrently.  相似文献   
5.
Social support during an ongoing illness has been shown to be beneficial for both the provider and the receiver, but people often struggle with offering effective, appropriate support. There is a lack of communication-focused training not specifically tied to caregiving or training that is designed for all social network members of a person experiencing a chronic illness, which we call interpersonal support providers (ISPs). We conducted a concurrent mixed-methods needs assessment, surveying both ISPs and support receivers, to understand communicative challenges and inform an evidence-based intervention. Analysis of results from an online survey (Nproviders = 91, Nreceivers = 97), consisting of five open-ended and 15 quantitative items, suggests that ISPs have difficulty managing their worries and emotions while providing comfort to others, which may impact support quality. In addition, ISPs and receivers both identify “listening” as a key skill for ISPs to hone, though ISPs feel they are more skilled at listening than receivers say they are. Lastly, ISPs feel they are good at sharing information and advice, but receivers often perceive it as patronizing or unhelpful. These results will inform the creation of an intervention for everyone offering emotional, esteem, and informational support to individuals with chronic illnesses.  相似文献   
6.
ABSTRACT Previous research has indicated that extraversion and neuroticism are substantially affected both by genotype and environment. This study assesses genetic and environmental influences on the other three components of the five-factor model of personality: Openness to Experience, Agreeableness, and Conscientiousness. An abbreviated version of the NEO Personality Inventory (NEO-PI) was administered to 82 pairs of identical twins and 171 pairs of fraternal twins reared apart and 132 pairs of identical twins and 167 pairs of fraternal twins reared together. Estimates of genetic and environmental effects for Openness and Conscientiousness were similar to those found in other studies of personality: Genetic influence was substantial and there was little evidence of shared rearing environment. Results for Agreeableness were different: Genetic influence accounted for only 12% of the variance and shared rearing environment accounted for 21% of the variance. Few significant gender or age differences for genetic and environmental parameters were found in model-fitting analyses.  相似文献   
7.
Increased attention has been directed recently to assisting persons with severe handicaps to express preferences concerning events in their lives. We evaluated a program for assessing choice-making skills to provide opportunities for persons with profound mental retardation to express food and drink preferences. In Experiment 1, the assessment procedure involving repeated, paired-item presentations resulted in active choice making and the identification of preferences for all 5 participants. Results also indicated that caregiver opinion was not predictive of participant food and drink preferences. A survey of service providers supported the importance of meal-related choices in this population. In Experiment 2, the practicality of the assessment procedure was supported by demonstrating that (a) routine caregivers could apply the procedure with appropriate supervision to provide choice opportunities, and (b) results of the procedure were predictive of participant choices when a less structured and more normal opportunity to express a preference was provided during regular mealtimes. Results are discussed in terms of extending the developing technology of preference and reinforcer identification to other important areas for persons with severe disabilities.  相似文献   
8.
We evaluated the effects of several choice-related variables on the work performance of adults with severe handicaps. After assessing client work preferences, three choice-related situations were presented: (a) providing clients with the opportunity to choose a work task, (b) assigning a preferred task, and (c) assigning a nonpreferred task. Results indicated that clients attended to work tasks almost twice as much when they chose their tasks and when assigned to work on preferred tasks versus when assigned to work on nonpreferred tasks. Results are discussed regarding the need to assess systematically the effects of choice-related variables.  相似文献   
9.
Characteristics and caregiving experiences of friends and family members caring for people with AIDS (PWAs) were examined. Based on a probability sample of informal AIDS caregivers ages 18–49 living in central cities of the United States (n = 260), analyses were conducted to (a) identify the sociodemographic characteristics of young central city caregivers; and (b) examine the effects of caregiver characteristics (relationship to PWA, gender, race/ethnicity, income, sexual orientation, HIV status, perceived susceptibility), and level of objective caregiving demands, on subjective caregiver burden. Results indicate that the largest group of caregivers in this age category are male friends of the PWA—a group not typically found among caregivers to persons with other types of illnesses. In general, gay or bisexual caregivers, caregivers who have traditional family ties to the PWA, men relative to women, and lower income caregivers, report the greatest burden. While level of caregiving demands represents the most influential predictor of caregiver burden, white and male caregivers experience greater burden, independent of level of involvement and other caregiver characteristics. Receiving instrumental support with caregiving buffers the impact of high objective demands on subjective burden.  相似文献   
10.
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.  相似文献   
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