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1.
Regional cerebral blood flow (rCBF) was measured during resting in 97 normal subjects, 19-68 years old. The results showed that the mean CBF level decreased progressively with age. The decrease was more prominent in frontotemporal and inferior Rolandic areas bilaterally. Frontal areas showed the highest values in all age groups. This hyperfrontality weakened somewhat with age. Mean CBF in the right hemisphere was significantly higher than in the left, as was flow in superior frontal, inferior frontal, and parietal areas. These asymmetries were age invariant. The age-related decrease of rCBF is interpreted as reflecting aging of the brain per se, although the influence of asymptomatic brain disease can not be ruled out. The flow asymmetries are interpreted as being related to functional lateralization of some aspects of attentional activation.  相似文献   

2.
Asymmetric resting blood flow in prefrontal and hemispheric regions, assessed by single photon emission computed tomography (SPECT), was examined as a potential biological marker for enhanced trait and state anxiety in 30 older men (ages 55-81). Average and asymmetric perfusion in dorsolateral, medial, and orbital regions of the prefrontal lobes was also assessed. Results indicated a significant association between lower levels of resting dorsolateral blood flow and greater state anxiety responses to a series of stressful provocations (measured on a separate occasion). A significant curvilinear (U-shaped) relation between asymmetric dorsolateral perfusion and state anxiety was also identified; increased asymmetric blood flow favoring either the right or the left dorsolateral region related to higher levels of state anxiety. However, this association was attenuated by age and systolic blood pressure. Resting perfusion in the dorsolateral region may represent a more reliable biological marker for state anxiety than trait anxiety in older men.  相似文献   

3.
Postural control during quiet standing was examined in typical children (TD) and children with cerebral palsy (CP) level I and II of GMFCS. The immediate effect on postural control of functional taping on the thighs was analyzed. We evaluated 43 TD, 17 CP children level I, and 10 CP children level II. Participants were evaluated in two conditions (with and without taping). The trajectories of the center of pressure (COP) were analyzed by means of conventional posturography (sway amplitude, sway-path-length) and dynamic posturography (degree of twisting-and-turning, sway regularity). Both CP groups showed larger sway amplitude than the TD while only the CP level II showed more regular COP trajectories with less twisting-and-turning. Functional taping didn’t affect sway amplitude or sway-path-length. TD children exhibited more twisting-and-turning with functional taping, whereas no effects on postural sway dynamics were observed in CP children. Functional taping doesn’t result in immediate changes in quiet stance in CP children, whereas in TD it resulted in faster sway corrections. Children level II invest more attention in postural control than level I, and TD. While quiet standing was more automatized in children level I than in level II, both CP groups showed a less stable balance than TD.  相似文献   

4.
Research into the perception of space, time and quantity has generated three separate literatures. That number can be represented spatially is, of course, well accepted and forms a basis for research into spatial aspects of numerical processing. Links between number and time or between space and time, on the other hand, are rarely discussed and the shared properties of all three systems have not been considered. I propose here that time, space and quantity are part of a generalized magnitude system. I outline A Theory Of Magnitude (ATOM) as a conceptually new framework within which to re-interpret the cortical processing of these elements of the environment.  相似文献   

5.
Hanley, Jin, Vanselow, and Hanratty (2014) described a functional analysis (FA) format that relied on a synthesis of multiple contingencies described by caregivers during open‐ended interviews. These interview‐informed synthesized contingency analyses (IISCA) provided effective baselines from which to develop socially validated treatments, but the synthesis precluded a precise understanding of individual contingencies influencing problem behavior. We conducted IISCAs and standard FAs (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) for nine children with autism to evaluate the likelihood of differentiation given a number of synthesized versus isolated variables. The IISCA was differentiated for all. The standard FA was differentiated for four; this number increased to six when we included precursors in the standard FA. We then compared treatments based on sets of differentiated analyses for four children. Treatment based on the IISCA was effective for all four; treatments based on the standard FA were effective for two. The role of synthesis in analysis is discussed.  相似文献   

6.
We studied a computational model of short term memory capacity that performs a simulated running memory span task using Hebbian learning and rapid decay of connection strengths to keep recent items active for later recall. This model demonstrates recall performance similar to humans performing the same task, with a capacity limit of approximately three items and a prominent recency effect. The model also shows that this capacity depends on decay to release the model from accumulating interference. Model findings are compared with data from two behavioral experiments that used varying task demands to tax memory capacity limits. Following additional theoretical predictions from the computational model, behavioral data support that when task demands require attention to be spread too thin to keep items available for later recall, capacity limits suffer. These findings are important both for understanding the mechanisms underlying short term memory capacity, and also to memory researchers interested in the role of attention in capacity limitations.  相似文献   

7.
The stability of the factor structure of mood was examined under two different experimental conditions, sleep deprivation and normal wakefulness In the first phase of the study, two different forms of a mood scale were administered to several college classes, and the ratings for each scale were intercorrelated and factored Eight interpretable factors emerged from each analysis, and the two sets of factors were highly congruent. In the second phase of the study subjects completed the mood ratings after staying awake all night or after getting a good night's rest Comparisons between the means for the two groups showed significant differences on 26 of the 44 variables included in the scale The scores for the sleep-deprived group were then intercorrelated and factored, and the factor structure was compared with the relevant factor structure obtained in the first phase of the study The results of the comparison showed that six of the eight factors appeared under both conditions of sleep deprivation and normal wakefulness Additional analysis indicated that a seventh factor appeared, but in the guise of different variables The only factor which failed to appear under sleep deprivation was elation. It was concluded that although variable ratings showed high sensitivity to the experimental operations, the basic structure of the underlying mood states remained remarkably stable The results indicate that the search for a list of basic mood states may be quite fruitful An important methodological implication was that a variable may be selected to measure a mood under various experimental operations with the assurance that the nature of the mood to be measured does not change as a result of those operations  相似文献   

8.
The brain is an intricate network, not only structurally but also functionally. On the functional level, connectivity in the brain is organized in separable yet interacting networks that support information processing by maintaining a ready state, even in the absence of external stimulation. It has been hypothesized that an insular-opercular network underlies the processing of emotionally salient information and that individual differences in functional connectivity within this network correspond to individual differences in trait anxiety. Here, we tested this relationship by applying graph analysis to multiple regions of interests delineating the insular-opercular network to estimate the characteristic path length that quantifies the overall information exchange efficiency within a given network. We found that people scoring high on the anxiety-related temperament-dimension harm avoidance had decreased insular-opercular network efficiency in the resting state, as indicated by a higher characteristic path length. Furthermore, people scoring high on harm avoidance showed generally reduced functional connectivity between brain regions; the relationship between harm avoidance and insular-opercular network efficiency remained significant when controlling for mean connectivity within this network. No such results were found for other resting-state networks. The results provide insights into how personality is organized in the human brain and point toward clinically relevant endophenotypes for affective and mood disorders.  相似文献   

9.
Pattern correlates of perceived size were studied by obtaining category judgments of the size of 100 random forms from 40 Ss who explored the forms visually and 40 Ss who explored them factually. Comparison of the modalities and contrasts with perceived complexity were made via intercorrelations of judgments and latencies, multiple regression analyses using factored form dimensions, and correlations with original form measures. By holding area of the forms constant, it was shown that perceived size can be related to characteristics of shape.  相似文献   

10.
11.
This study examined social network characteristics of adults aged 70 to 90 years in relation to widowhood and illness in France, Germany, Japan, and the United States. Participants were drawn from representative samples from each of the 4 countries (total N = 1,331). Resource deficit profiles based on whether respondents were widowed, ill, both, or neither were directly related to social network characteristics for German and Japanese adults, were differentially related by gender and age for French adults, and were not related to social networks of Americans. Country, gender, and age differences in total network size, proportion of close network members, and frequency of contact with network members are reported. Similarities and differences found in the associations between normative late-life deficits and social network characteristics in the 4 countries point to the importance of investigating sociocultural factors that mediate the impact of resource loss and afford life quality in very old age.  相似文献   

12.
13.
Based on two factor analyses of data from 67 right-handed undergraduates, a laterality quotient based on forward memory spans, spatial minus digit, divided by their sum, was devised. The hemispheric balance factor for which this quotient served as the principal marker had significant positive loadings by the laterality quotient for the Edinburgh Handedness Questionnaire and by a measure of repressive tendencies, the Marlowe-Crowne Social Desirability Scale. Scores from this factor were positively related to global as opposed to analytic perception as measured by the Navon tachistoscopic task. This factor was unrelated to the trait anxiety and working short-term memory factors which also emerged. Trait anxiety was negatively related to global perception. The results raise the possibility that greater degrees of right-handedness may be related to the release of the nondominant right hemisphere from inhibition and that working short-term memory may not be lateralized.  相似文献   

14.
15.
The Dunn Marriage Role Expectation Inventory was used to compare the marriage-role expectations of female university students enrolled in an introductory marriage and family course in 1961 (N=72), 1972 (N=58), and 1978 (N=115). The 1978 group was significantly more egalitarian than the 1961 group in overall marriage-role expectations and on each of the seven subcategories of authority, homemaking, child care, personal characteristics, social participation, education, and employment and support. The 1972 group was also found to be significantly more egalitarian than the 1961 group in overall marriage-role expectations and on all subcategories except authority. The 1978 group was significantly more egalitarian than the 1972 group only on authority and homemaking, with no significant differences on overall marriage-role expectations or on the other five subscales. The significant move toward more egalitarian attitudes toward authority and homemaking is accentuated by the fact that only 6 years separate the 1972 and 1978 groups, while there is an 11-year difference between the 1961 and 1972 groups.The data were collected in February 1961, January 1972, and September 1978. Special acknowledgment and appreciation are expressed to Jessie Ringo (retired) for making the 1961 data available for this study and to William F. Kenkel, Department of Sociology, University of Kentucky, for his helpful comments.  相似文献   

16.
IntroductionAlzheimer's disease may modify moral judgment.ObjectiveIn two studies, we assessed the impact of dementia on blame and forgiveness. Study 1 compared the ways in which young adults, older adults, and older adults with dementia cognitively integrated two factors. Study 2 assessed the number of different factors that older adults with dementia were able to integrate during these moral judgments.MethodThe participants recorded their moral judgements in a blame task and in a forgiveness task. In study 1, the two questionnaires contained scenarios built from the combination of two factors. In study 2, the participants were confronted with the same tasks under three different conditions with scenarios that combined three, four or five factors.ResultsThe data from study 1 showed that the older adults with dementia did not combine the two factors in the same way as young adults did: the combination depended on the type of moral judgment. Study 2 revealed differences in moral judgment between older adults with dementia and adults without dementia in all tasks (i.e. with three, four or five factors combined).ConclusionDementia has an impact on moral judgments. Moral judgment among people with dementia is both task- and condition-dependant.  相似文献   

17.
《Behavioural neurology》1999,11(3):173-183
Both Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share a common neuropathological marker, the presence of Lewy bodies in brain stem and basal forebrain nuclei. DLB, in addition, is associated with Lewy bodies in the neocortex, and, in it's more common form, with Alzheimer-type pathological markers, particularly amyloid plaques. Published neuropsychological studies have focused on the differential profiles of DLB and Alzheimer's disease (AD). However, it is presently unclear whether DLB should be classified as a variant of AD or PD. In the present study we compare a healthy age-matched control group with three groups of patients, one with DLB, and two with PD. One of the PD groups was early in the course (PD-E) and the second, more advanced group (PD-A), was matched on severity of cognitive impairment with the DLB group. The results show that DLB was associated with a different pattern of neuropsychological impairment than the PD-A group, particularly in tests believed to be mediated by prefrontal cortical regions.  相似文献   

18.
Both Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share a common neuropathological marker, the presence of Lewy bodies in brain stem and basal forebrain nuclei. DLB, in addition, is associated with Lewy bodies in the neocortex, and, in it's more common form, with Alzheimer-type pathological markers, particularly amyloid plaques. Published neuropsychological studies have focused on the differential profiles of DLB and Alzheimer's disease (AD). However, it is presently unclear whether DLB should be classified as a variant of AD or PD. In the present study we compare a healthy age-matched control group with three groups of patients, one with DLB, and two with PD. One of the PD groups was early in the course (PD-E) and the second, more advanced group (PD-A), was matched on severity of cognitive impairment with the DLB group. The results show that DLB was associated with a different pattern of neuropsychological impairment than the PD-A group, particularly in tests believed to be mediated by prefrontal cortical regions.  相似文献   

19.
The roles assigned to nature and nurture in the acquisition of functional specializations have been modified in recent years due to increasing evidence that experience-dependent processes are more influential in determining a brain region’s functional properties than was previously supposed. Consequently, one may study the developmental principles that play a role in the acquisition of functional specializations. This article studies the hypothesis that a combination of structure-function correspondences plus the use of competition between modules leads to functional specializations. This principle has been instantiated in a family of neural network architectures referred to as “mixtures-ofexperts” architectures. These architectures are sensitive to structure-function relationships in the sense that they often learn to allocate to each task a network whose structure is well matched to that task. The viewpoint advocated here represents a middle ground between nativist and constructivist views of modularity.  相似文献   

20.
In this investigation, intimate partner support, relationship satisfaction, and separation proneness were assessed for four types of people: men in a relationship with a woman (MRW), men in a relationship with a man (MRM), women in a relationship with a man (WRM), and women in a relationship with a woman (WRW). Men and women in same‐sex relationships received more support, were more satisfied, and reported fewer thoughts of separating than their counterparts in opposite‐sex relationships. The effect of relationship type on satisfaction was not significant once the amount of received support was controlled. The implications of these findings for understanding the support process in same‐sex relationships are discussed.  相似文献   

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