The role of functional and perceptual attributes: evidence from picture naming in dementia

We examined the performance of a group of people with moderately severe Alzheimer's type dementia on a naming task. We found that functional information plays an important role in determining naming performance on both living and non-living things. Perceptual information may play some role in naming living things. We also found some evidence that the semantic category to which an item belongs may also have some effect on naming performance. We argue that both the sensory-functional and domain-specific knowledge hypotheses may be correct: the brain is to some organized on taxonomic grounds, while the semantic representations of living and non-living things depend differentially on perceptual and functional information. These representations can be differentially disrupted by damage to modality-specific stores. At a moderate level of severity, dementia causes global damage that has the effect of disrupting both the localized taxonomic and the modality-specific stores. We discuss the nature of functional information.     

The snodgrass picture fragment completion test: Alternate-form reliability

In two studies, the alternate-form reliability of the Snodgrass picture fragment completion test of implicit memory (Snodgrass, Smith, Feenan, & Corwin, 1987) was examined. In this test, identification thresholds are established for fragmented pictures. The same fragmented pictures are then shown again, intermixed with new fragmented pictures. Implicit memory is indicated by a decrease in identification threshold from the first to second presentation. Alternate-form reliability was low to moderate, depending on the measure used, regardless of the length of the test. A third study showed that explicit memory instructions did not increase the reliability. Recommendations for use of the test in correlational and experimental research are presented.     

The use of the peabody picture vocabulary test with emotionally disturbed adolescents

The validity and reliability for the Peabody Picture Vocabulary Test (PPVT) was estimated with 52 nonpsychotic emotionally disturbed adolescents. Approximately 6 months after an initial administration of the PPVT and the Peabody Individual Achievement Test (PIAT), all children were retested. Significant increases in PPVT IQ and PIAT reading comprehension scores were found upon readministration. The internal consistency estimate for the initial PPVT administration showed considerable consistency in responding. A modest temporal stability estimate indicated a fair amount of fluctuation in scores over time. Concurrent validity coefficients for the PPVT indicated moderate to dependable relationships with PIAT subtests. Predictive validity estimates for the PPVT suggested moderate relationships with future achievement, accounting for some 26% of the variability in total achievement.     

Semantic feature knowledge and picture naming in dementia of Alzheimer's type: a new approach

This study addresses continuing controversies concerning the nature of semantic impairment in early dementia of the Alzheimer type (DAT), and the relationship between conceptual knowledge and picture naming. A series of analyses of fine-grained feature knowledge data show that: (1) distinctive features of concepts were more vulnerable than shared; (2) the amount of attribute knowledge about a concept was associated reliably, and in a graded fashion, with the ability to name a picture of that item; (3) sensory features were differentially important in naming; and (4) the degree of disruption to different types of attribute knowledge did not vary between items from living and nonliving domains. These findings are discussed in the context of contemporary cognitive and computational models of semantic memory organisation.     

Comparing diagnostic validity of the TAT and a new picture projective test

Diagnostic validity of the TAT and a new picture projective test, the PPT, were compared for normal, depressed, and psychotic subjects. Generally, the PPT elicited more positive emotional tone, more activity, and fewer thematic deviations than the TAT. The PPT and TAT were essentially equal in the capacity to discriminate between stories of normal and depressed subjects; however, the PPT was superior in differentiating psychotics from normals and depressives. On the PPT, depressives told stories with gloomier emotional tone and psychotics made more perceptual distortions, thematic and interpretive deviations. None of these differences were apparent on the TAT. The PPT pictures seem to have more diagnostic validity than the TAT stimuli.     

Cross-cultural studies of dementia: use of a Chinese version of the Blessed-Roth Information-Memory-Concentration test in a Shanghai dementia survey

A culturally adapted Chinese version of the Blessed-Roth Information-Memory-Concentration test (CIMC) was used in a dementia screening survey of a probability sample of 5,055 elderly Shanghai residents. The individual items on the CIMC that best predicted the overall score were similar to the best predictor of an American version of the IMC. Performance on the CIMC was markedly affected by the level of education or lack thereof. In a subsample for whom clinical diagnoses were obtained, it was possible to establish cutoff values on the CIMC by stratifying the sample according to education.     

The use of configural analysis for the evaluation of test scoring methods

A method based on configural analysis has been given whereby test scoring techniques can be evaluated to see if they have optimal validity. Configural analysis has also been used to show how three well known item scoring techniques, multiple regression, total score, and multiple cut-off, imply (for optimal validity) certain conditions on the answer pattern means. The method is illustrated by a worked example.We are indebted to Professor James G. Taylor for his helpful suggestions.     

Comparison of Egyptian and Canadian children on a picture apperception test

Individualism-collectivism theory predicted that Egyptian and Canadian children's performance would differ on relevant scales of the Roberts Apperception Test for Children (RATC). The RATC was administered to 34 Egyptian and 34 Canadian children ages 6-13 years. Canadian children scored higher on autonomy and lower on receiving support from others and parental limit setting. At older ages, Egyptian children manifested less rejection, desire for help from others, and aggression. There were no cultural differences in anxiety or depression and few differences on indicator and resolution scales related to understanding the task and resolving problems. The findings validated cross-cultural use of the RATC and demonstrated that the increasingly general theory of collectivism allowed meaningful predictions about personality and clinical traits.     

The role of encoding in reality monitoring: A running memory test with Alzheimer's type dementia

Reality monitoring refers to the discrimination between memories of internal and external events (e.g., Johnson & Raye, 1981). A total of 28 healthy older adults and 28 older adults with Alzheimer's type dementia (DAT) were asked to perform or to imagine performing simple action statements in a running memory test. This task required participants to tell whether the action statement had been carried out or imagined, or whether it was new at unpredictable intervals. The results indicated that older adults with DAT had greater difficulty in reality monitoring than did the healthy control group. The finding is discussed in terms of the role of working memory functions in reality monitoring.     

The role of encoding in reality monitoring: a running memory test with Alzheimer's type dementia

Reality monitoring refers to the discrimination between memories of internal and external events (e.g., Johnson & Raye, 1981). A total of 28 healthy older adults and 28 older adults with Alzheimer's type dementia (DAT) were asked to perform or to imagine performing simple action statements in a running memory test. This task required participants to tell whether the action statement had been carried out or imagined, or whether it was new at unpredictable intervals. The results indicated that older adults with DAT had greater difficulty in reality monitoring than did the healthy control group. The finding is discussed in terms of the role of working memory functions in reality monitoring.     

Insight in frontotemporal dementia: conceptual analysis and empirical evaluation of the consensus criterion "loss of insight" in frontotemporal dementia

The objective of this study was to suggest a new formulation of the core research diagnostic consensus criterion "loss of insight" in frontotemporal dementia (FTD). Eight patients with FTD (diagnoses made by interviews, medical and neuropsychological examination, CT scan, and regional cerebral glucose metabolism measured by positron emission tomography (PET) participated in the study). The results indicated that insight was present in three out of eight patients, and that insight appears to be a heterogeneous concept. Two types of insight emerged: Emotional insight associated with frontotemporal functions, and cognitive insight, related to posterior cognitive functions. These results suggest that loss of insight should not serve as a core criterion on FTD, but serves well as a supportive criterion of the disease.