The Framingham Heart Study clock drawing performance: normative data from the offspring cohort.

UNLABELLED: BACKGROUND/STUDY CONTEXT: Although the Clock Drawing Test (CDT) is a popular tool used to assess cognitive function, limited normative data on CDT performance exist. The objective of the current study was to provide normative data on an expanded version of previous CDT scoring protocols from a large community-based sample of middle to older adults (aged 43 to 91) from the Framingham Heart Study. METHODS: The CDT was administered to 1476 Framingham Heart Study Offspring Cohort participants using a scoring protocol that assigned error scores to drawn features. Total error scores were computed, as well as for subscales pertaining to outline, numeral placement, time-setting, center, and "other." RESULTS: Higher levels of education were significantly associated with fewer errors for time-setting (Command: p < .001; Copy: p = .003), numerals (Command: p < .001), and "other" (Command: p < .001) subscales. Older age was significantly associated with more errors for time-setting (Command: p < .001; Copy: p = .003), numerals (Command: p < .001), and "other" (Command: p < .001) subscales. Significant differences were also found between education groups on the Command condition for all but the oldest age group (75+). CONCLUSION: Results provide normative data on CDT performance within a community-based cohort. Errors appear to be more prevalent in older compared with younger individuals, and may be less prevalent in individuals who completed at least some college compared with those who did not. Future studies are needed to determine whether this expanded scoring system allows detection of preclinical symptoms of future risk for dementia.

Alterations in working memory as a function of leukoaraiosis in dementia.

Dementia research suggests executive dysfunction is best understood within the context of disease-specific neuropathology. Leukoaraiosis (LA) results in executive dysfunction yet little is known about its impact on specific aspects of working memory (WM). This study aimed to investigate the relationship between MRI LA severity and WM in dementia. A visual rating scale was used to assign patients with dementia into groups with minimal-mild LA (Low LA; n=34) and moderate-severe LA (High LA; n=32). A modified Digit Span Backward Task consisting of 3-, 4-, and 5-span trials measured specific components of WM. Short-term storage and rehearsal in WM were assessed by the total number of digits reported regardless of recall order (ANY-ORDER; e.g., 47981 recalled '18943', score=4). Mental manipulation in the form of disengagement and temporal re-ordering was assessed by the total number of digits recalled in correct position (SERIAL-ORDER; e.g., 47981 recalled '18943', score=3). There was no difference between LA groups on ANY-ORDER comparisons. The High LA group obtained lower SERIAL-ORDER scores than the Low LA group. Stepwise regression analyses were conducted that first entered MMSE scores then composite z-scores reflecting executive functioning, language and memory. ANY-ORDER performance variance was explained solely by dementia severity. SERIAL-ORDER performance variance was further explained by executive dysfunction. Results suggest that high degrees of LA do not interfere with immediate (digit) recall but do interfere with disengagement and temporal re-ordering. LA may disconnect the frontal lobes from subcortical and cortical structures that form the neuronal networks critical for these WM functions.

Capacity to maintain mental set in dementia.

Two experiments investigating the capacity to sustain mental set in dementia were conducted. Experiment 1 analyzed performance of a non-demented control group (NC), participants with Alzheimer's disease (AD) and participants with ischemic vascular dementia (IVD) on the Boston Revision of the Wechsler Memory Scale Mental Control subtest (MC). On simple tasks there were no between-group differences after controlling for time to completion. On complex tasks, NC participants outperformed both dementia groups and AD participants obtained higher accuracy indices than IVD participants. The IVD group produced a disproportionate number of commission errors regardless of task complexity. The AD group tended to produce more omission errors on more difficult measures of mental set. Individual task performance was divided into three sections-first, middle, and last. IVD participants made fewer and fewer correct responses over all three sections, whereas performance of AD participants leveled off by the middle section with no further decline. Experiment 2 compared letter fluency performance among NC, AD and IVD groups, and participants with dementia secondary to idiopathic Parkinson's disease (PD). For all letter cues, IVD and PD participants generated fewer responses than NC and AD participants. However, IVD and PD participants generated a larger proportion of words than AD and NC participants within the first 15 s. As the task progressed, the output of IVD and PD participants dropped precipitously. These findings indicate that failure to maintain mental set is not a diffuse or general cognitive disability. Rather, failure to maintain mental set in dementia may be best understood within the context of predictable and specific within-task time epochs.

Speed and memory in the WAIS-III Digit Symbol--Coding subtest across the adult lifespan.

The primary role of speed in determining Digit Symbol scores is well established. Among the important questions that remain to be resolved are: (1) whether speed accounts for all of the age-related decline in Digit Symbol scores, and (2) whether memory ability makes any significant contribution to Digit Symbol performance, especially after controlling for speed. We analyzed data from the WAIS-III/WMS-III standardization sample to resolve these issues. As expected, speed (Digit Symbol-Copy) correlated very strongly with Digit Symbol--Coding. Memory (Digit Symbol--Incidental Learning or WMS-III index scores) correlated more moderately with Digit Symbol-Coding. Even after controlling for variance in Coding explained by Copying, a statistically significant proportion of the residual variance was explicable in terms of memory functions. The contribution of memory to Digit Symbol--Coding, while relatively small, is real. In addition, a small portion of the age-associated decline in Coding scores cannot be accounted for by Copying scores.

Assessing nonverbal memory with the Biber Figure Learning Test-Extended in temporal lobe epilepsy patients.

Material-specific memory dysfunction was assessed using a nonverbal, visuospatial, supraspan learning test, the Biber Figure Learning Test-Extended (BFLT-E), in 71 left-hemisphere language-dominant epilepsy patients prior to anterior temporal lobectomy (ATL) and in 48 age-matched healthy subjects. Two matched forms of the BFLT-E yielded comparable scores, indicating that this task may be used to track memory performance over time in individual patients. Right temporal lobe epilepsy (RTLE) and left temporal lobe epilepsy (LTLE) patients performed below healthy subjects on all free-recall measures. RTLE, but not LTLE, patients also differed from healthy subjects in recognition memory discrimination. Furthermore, the RTLE patients performed below LTLE patients on measures specific to long-term memory abilities. The BFLT-E appears to be a useful clinical tool for assessing different components of visuospatial memory in patients with lateralized mesial temporal lobe (MTL) dysfunction. The test is sensitive to visuoconstructional problems associated with various types of brain damage, but it also distinguishes material-specific, nonverbal, visuospatial memory impairments in patients with neurological dysfunction in the non language-dominant right temporal lobe.

The Biber Cognitive Estimation Test.

Normative data from 113 participants, and cross-validation data from 49 additional participants, are presented for the Biber Cognitive Estimation Test (BCET), a 20-item test with five estimation questions in each of four categories: time/duration, quantity, weight, and distance. In Study 1, the range of normal answers is provided for each item, and a cut-off for impaired performance is suggested. Although very low IQ or education levels would be expected to invalidate this test as a measure of estimation skills, participants in the current sample made few errors. In Study 2, a cross-validation suggested a slightly more conservative cut-off score for abnormality. Study 3 examined cognitive estimation in demented (dementia of the Alzheimer's type and dementia syndrome of Parkinson's disease) versus intact elderly participants. Results indicated that the BCET was able to distinguish between demented and intact elderly participants.

Decoding digit symbol: speed, memory, and visual scanning.

The authors evaluated the relative contributions of speed, memory, and visual scanning to Digit Symbol score in a sample of young adults (N = 87). Speed (Symbol Copy) explained 35% of Digit Symbol variance; only half of this was attributable to graphomotor speed (Name Printing), implying a role for perceptual speed. Visual-scanning tests (e.g., Symbol Scan) explained (on average) 34% of Digit Symbol variance, much of which was independent of perceptual-motor speed, establishing an important role for visual-scanning efficiency in Digit Symbol performance. By contrast, memory tests (on average) explained only 4% to 5% of Digit Symbol variance: statistically significant but clearly subsidiary, although a visual memory composite correlated more strongly with Digit Symbol. The Digit Symbol incidental learning procedures did, however, correlate moderately with other memory measures, suggesting that they are valid memory screening devices.

Exploring an integrative model of infant behavior: what is the relationship among temperament, sensory processing, and neurobehavioral measures?

Traditionally, developmental psychology, occupational/physical therapy, and behavioral pediatrics view similar infant behaviors from temperament, sensory processing, or neurobehavioral theoretical perspectives. This study examined the relations between similar and unique summary scores of three infant assessments (Early Infancy Temperament Questionnaire - EITQ, the Infant Sensory Profile - ISP, and the NICU Network Neurobehavioral Scale - NNNS) in a healthy sample of 100, one-month-old infants. A Principal Components Analysis of selected subscale scores derived from the three assessments suggested a three-factor model. Temperament and sensory summary scores had the strongest relations on two factors: Sensory-Affective Reactivity and Engagement. A third factor had strong relations between state regulation and motor competence. This new integrative model also validates an existing model and expands explanation of infant behavior across disciplines and methods which have significant implications for assessment, intervention, and management practices.

Clock drawing performance in cognitively normal elderly.

The Clock Drawing Test (CDT) is a common neuropsychological measure sensitive to cognitive changes and functional skills (e.g., driving test performance) among older adults. However, normative data have not been adequately developed. We report the distribution of CDT scores using three common scoring systems [Mendez, M. F., Ala, T., & Underwood, K. L. (1992). Development of scoring criteria for the Clock Drawing Task in Alzheimer's Disease. Journal of the American Geriatrics Society, 40, 1095-1099; Cahn, D. A., Salmon, D. P., Monsch, A. U., Butters, N., Wiederholt, W. C., & Corey-Bloom, J. (1996). Screening for dementia of the Alzheimer type in the community: The utility of the Clock Drawing Test. Archives of Clinical Neuropsychology, 11(6), 529-539], among 207 cognitively normal elderly. The systems were well correlated, took little time to use, and had high inter-rater reliability. We found statistically significant differences in CDT scores based on age and WRAT-3 Reading score, a marker of education quality. We present means, standard deviations, and t- and z-scores based on these subgroups. We found that "normal" CDT performance includes a wider distribution of scores than previously reported. Our results may serve as useful comparisons for clinicians wishing to know whether their patients perform in the general range of cognitively normal elderly.

Role of frontal cortex in inferential reasoning: evidence from the word context test.

PROBLEM: Inferential reasoning in language involves the ability to deduce information based on context and prior experience. This ability has been generally studied as a right-hemisphere function. Recent research, however, has suggested that inferencing involves anterior regions of both the left and right hemispheres. METHODS: We further explored this idea by testing a group of non-aphasic, focal frontal patients (right and left hemisphere) on a new test of inferencing, the Word Context Test. The Word Context Test requires examinees to identify the meaning of a made-up word (e.g., prifa) based on its use in a series of sentences. FINDINGS: Patients with frontal lobe lesions were significantly impaired on this task relative to a group of age- and education-matched controls. Contrary to earlier research focusing on a special role for the right hemisphere in inferencing, there was considerable overlap in performance of right- and left-frontal patients, with right-frontal patients performing better. CONCLUSIONS: These findings suggest that inferencing is disrupted following focal frontal injury and have implications for discourse comprehension in non-aphasic patients.

Digit Symbol-Incidental Learning in the WAIS-III: construct validity and clinical significance.

We analyzed WAIS-III/WMS-III standardization data for evidence of the construct validity and clinical utility of the Digit Symbol-Incidental Learning procedures (Pairing and Free Recall). Scores on both tests correlated moderately with WMS-III memory index scores (mean r=.38 for Pairing and .36 for Free Recall). Cutoff scores can be used to identify younger and older adults likely to suffer from memory impairment. In the standardization sample (which excludes neurological patients), these have moderate positive predictive power (averaging .56 if either test yields a positive finding), moderate negative predictive power (.76), and high specificity (.88), but low sensitivity (.35). In a clinical sample, the same cutoff scores were much more sensitive, correctly identifying 88% of a group of patients with Alzheimer's Disease. Examinees who obtain these low scores should receive follow-up memory testing. Very high scores are associated with a reduced risk of memory impairment.

Characterizing alterations in executive functioning across distinct subtypes of cortical and subcortical dementia.

Differential patterns of executive function deficits (EFD) exist in cortical and subcortical dementia; however, little work exists attempting to integrate these findings into a conceptual framework. The current study aimed to characterize EFD in cortical and subcortical dementia. Patients with Alzheimer's disease (AD; n = 65), subcortical ischemic vascular dementia (IVD; n = 64), or Parkinson's disease with dementia (dPD; n = 21) completed a variety of measures purported to require executive systems. We extracted variables of interest from measures shown in a growing body of literature to be associated with EFD in dementia. These measures included the Boston Revision of the WMS Mental Control subtest, letter fluency, WAIS-R Similarities subtest, CVLT, the Graphical Sequence Test-Dementia version, and Clock Drawing. When submitted to a PCA with varimax rotation, these variables produced a four-component solution (62% of the variance). Component 1 appeared to reflect adequacy of working memory, Component 2 irrelevant or context nonspecific interference, Component 3 reflected response preparation and Component 4 relevant or context-specific interference. Post hoc analyses of z-transformed composite scores revealed that AD differentially affected context-specific interference, IVD and dPD disrupted working memory and response preparation while IVD differentially affected context non-specific interference. EFD in dementia can be divided into specific components that are differentially impaired by cortical and subcortical dementias. Implications for an overall conceptual framework of EFD in dementia are discussed.

Error analysis of the nine-word California Verbal Learning Test (CVLT-9) among older adults with and without dementia.

The nine-word California Verbal Learning Test (CVLT-9; Libon et al., 1996; Spreen & Strauss, 1998) is a verbal list learning task used to assess declarative memory impairment among dementia patients. The present study sought to investigate the neuro-cognitive mechanisms that underlie the production of intrusions and perseverations on the list A, free recall learning trials, and the false positive responses made on the delayed recognition condition. Patients with probable Alzheimer's disease (AD), Ischaemic Vascular Dementia associated with periventricular and deep white matter changes (IVD), and individuals without dementia (NC) were studied. Between-group analyses showed that AD participants produced more initial intrusion errors, and perseverated on those same intrusion errors across list A learning trials than IVD or NC participants. Also, as participants with dementia produced initial free recall intrusion errors, the semantic organization of their responses on the 'animal' word list generation task declined (Giovannetti-Carew, Lamar, Cloud, Grossman, & Libon, 1997). On the delayed recognition test condition, within-group analyses revealed that the IVD group endorsed more list B interference foils, than other errors. AD participants endorsed semantically related foils and list B interference foils. In addition, as participants with dementia endorsed more list B interference foils, more perseverations were produced on the Graphical Sequence Test - Dementia Version (Lamar et al., 1997). These results were interpreted within the context of the semantic knowledge, and executive functions deficits that typify AD and IVD, respectively.

Global-local visual processing in posttraumatic stress disorder.

The purpose of this study was to examine a behavioral index of hemispheric asymmetry (i.e., visual hierarchical attention) in posttraumatic stress disorder (PTSD), a disorder characterized by anxiety and other emotional symptoms. A reaction time based, computerized, global-local visual paradigm was administered to 26 PTSD-diagnosed and 22 psychopathology-free right-handed, male Vietnam War zone veterans. Results indicated that PTSD-diagnosed veterans displayed slower reaction times to all targets than the no-mental disorders comparison sample. However, findings also revealed a Group x Target location interaction in which the PTSD group was slower than the no-disorders comparison sample to respond to local, but not global, targets. Moreover, relative global bias was greater among PTSD-diagnosed veterans than their no-diagnosis counterparts. Findings provide partial support for the hypothesis that PTSD may be associated with a functional cerebral asymmetry favoring the right hemisphere.

Clock drawing errors in dementia: neuropsychological and neuroanatomical considerations.

OBJECTIVES: A clock drawing test scoring system is presented to explore the neuropsychological/neuroanatomic components underlying clock drawing in patients initially diagnosed with Alzheimer disease, ischemic vascular dementia associated with white matter alterations, and Parkinson disease. METHODS: Fourteen clock drawing test errors were scored to create 4 clock drawing test subscales that assess different underlying cognitive operations. RESULTS: In the command condition, errors on the Time subscale were correlated with impairment on executive control measures. In the copy condition, errors on the Perseveration/Pull to Stimulus subscale was also correlated with executive control measures. Patients presenting with mild (low) magnetic resonance imaging white matter alterations, significant (high) white matter alterations, and Parkinson disease were compared. In the command condition, the low white matter alterations group made fewer total errors than the Parkinson disease group. In the copy condition, the low white matter alterations group made fewer errors on the Time, Spatial Layout, and Perseveration/Pull to Stimulus clock drawing test subscales than the high white matter alterations or Parkinson disease groups. Few differences were noted between the high white matter alterations and Parkinson disease groups. DISCUSSION: Our data suggest that heavy demands on executive control associated with the interruption of large-scale cortical-subcortical neural networks underlie impairment in clock drawing in mild dementia.

Errors produced on the mini-mental state examination and neuropsychological test performance in Alzheimer's disease, ischemic vascular dementia, and Parkinson's disease.

The authors investigated whether MMSE indices designed to measure temporal and physical orientation, declarative memory, language, working memory, and motor/constructional function could differentiate patients with different dementia diagnoses: Alzheimer's disease (AD), ischemic vascular dementia (IVD), or Parkinson's disease (PD). MMSE summary scores did not differ (AD, 21.4; IVD, 21.1; PD, 22.3). The AD group scored lower than IVD or PD on temporal orientation and declarative memory, IVD lower than AD on motor/ constructional and working memory. The IVD and PD groups made more errors in writing a sentence and copying intersecting pentagons. Significant correlations were found between the orientation indices and neuropsychological tests of naming and memory, and between the working memory and motor/constructional indices and tests of executive control. Such analyses of MMSE performance could assist in formulating referral questions for cognitive assessment and in tracking the course of dementing illnesses.