Focal left temporal slow EEG activity is related to a verbal recent memory deficit in a non-demented elderly population

Neuropsychological measures of memory and cognition and topographical quantitative EEG were obtained on 35 healthy, non-demented, right-handed, elderly subjects aged 60-81. All were free of medications which impair cognition. They were divided into a left temporal slow abnormality group (n = 9) and a control group (n = 26) on the basis of topographically normalized measures of both delta and theta activity for the left temporal lead T3. The group with left temporal slow activity was significantly deficient on measures of memory savings and memory losses derived from the Logical Memory (Story Recall) Test in the Wechsler Memory Scale--Revised. There were no significant differences between these two groups on the non-memory cognitive tasks. This predominant verbal recent memory deficit profile is reasonably similar to the neuropsychological deficit profile of very mildly demented Alzheimer patients. Because left temporal slow EEG activity is also the predominant EEG abnormality in mild Alzheimer patients, a prospective study should be done to determine if this abnormality in non-demented elderly subjects is most often a preclinical sign of Alzheimer's disease.     

Serum alpha 1-antichymotrypsin in senile dementia]

To evaluate the clinical significance of serum alpha 1-Antichymotrypsin (ACT) as an early diagnostic marker of senile dementia of Alzheimer type (SDAT), we measured 333 healthy and not demented elderly subjects, 27 cases SDAT and 25 cases of vascular dementia (VD). For the measurement, a new high-sensitivity method, double antibody radioimmunoassay method was developed. In healthy elderly subjects, the mean value of serum ACT was 0.229 mg/ml. A tendency towards increase of ACT with aging was noted but was not significant. The serum level of ACT in the SDAT patients was significantly higher (0.309 mg/ml) compared with the healthy elderly subjects and the VD patients (0.226 mg/ml) (p < 0.01). We concluded that in the patients with SDAT, there was an overproduction of ACT and the serum value of ACT was markedly elevated. The measurement of serum ACT is very useful (sensitivity = 88.9%, specificity = 68.7%; cut-off value = 0.250 mg/ml) for the early differential diagnosis of senile dementia.     

Different regulation of adrenocorticotropin and cortisol secretion in young, mentally healthy elderly and patients with senile dementia of Alzheimer's type.

Previous studies suggest that an alteration of the neuroendocrine system may particularly occur in senile dementia of Alzheimer's type (SDAT). In the present study the reactivity of the hypophyseal-adrenocortical axis (HPA) in the elderly was assessed by hormonal stimulation of the hypophysis. Twelve young men (aged 21-24 yr), 15 mentally healthy elderly (aged 65-90 yr), and 12 patients with SDAT (aged 60-84 yr) received an iv bolus injection containing 50 micrograms CRH and 0.5 IU lysine vasopressin after a baseline period of 2 h. ACTH, cortisol, and dehydroepiandrosterone secretion was monitored over a period of 2 h before and after the injection. The baseline ACTH concentrations were increased in both groups of elderly, the baseline cortisol levels were not different in either group. The peak ACTH and cortisol levels were significantly elevated in the mentally healthy elderly, whereas senile demented patients showed a rise comparable with that in the young subjects. Moreover, in the demented patients the post-stimulus decline in plasma ACTH levels seemed to be delayed. Dehydroepiandrosterone was significantly lowered in subjects of all ages. Our results demonstrate an enhanced reactivity of the HPA in mentally healthy elderly. This is possibly due to a diminished sensitivity of the feedback regulation to glucocorticoids. However, SDAT patients had, compared to healthy elderly subjects, an attenuated response to CRH/lysine vasopressin and a prolonged ACTH secretion, indicating alterations of the HPA in this disease.     

Age differences in the vulnerability of facial recognition memory to proactive interference

A facial recognition memory task was administered to 16 young subjects (age range 18-30) and 28 elderly subjects (age range 63-83). A continuous recognition paradigm was used, in which subjects were instructed to identify the repeated faces in an ongoing series of faces presented on a video monitor screen. A signal detection analysis of the data revealed a mild recognition memory deficit in the elderly, due mainly to an increase in false positives during the second half of the test session. This age-specific increase in late-session false alarms may be a result of increased sensitivity of the aged subjects to proactive interference from previously presented faces. Increasing the length of the delay between the initial and repeat presentation of a face decreased recognition accuracy in both groups, but the young subjects were more sensitive to the delay interval effect than the elderly. Multiple presentations of faces produced a comparable improvement in the recognition accuracy of both young and old subjects. The elderly subjects exhibited a more liberal response bias than the young subjects, indicating that impaired memory task performance of the aged subjects cannot be attributed to a more conservative test-taking strategy.     

Mean cerebral transit time in demented and normal elderly persons

The mean cerebral transit time (MCTT) was measured in 31 elderly subjects, approximately half of whom suffered from chronic dementing illness. The results indicated a significant correlation between the MCTT and arm-to-head circulation time. Both times increased significantly with age. There was no difference in MCTT between demented and non-demented patients.     

Differentiating Alzheimer's disease from Huntington's disease with the Wechsler Memory Scale-Revised

The WMS-R represents a significant improvement over the original version of the WMS. Patterns of performance on the five WMS-R indices successfully differentiated patients with a "cortical" (that is, DAT) from patients with a "subcortical" (that is, HD) dementia. The differences between ACI and GMI also indicated that DAT patients' attention and concentration were better preserved than those of equally demented HD patients. Analyses of the differences between GMI and DMI indicated that rapid forgetting was more apparent for DAT than for HD patients in the early stages of these disorders. When savings scores for the Logical Memory and Visual Reproduction tests were used to examine retention over a 30-minute period, both mildly and moderately demented DAT patients demonstrated more rapid forgetting than did HD patients with similar levels of cognitive decline. Discriminant analyses performed with these indices of forgetting showed 95 per cent accurate classification of DAT and elderly controls, and 79 per cent correct classification of DAT and HD patients. Assessment of the patients' tendencies to make prior-item intrusion errors on the Visual Reproduction tests of the WMS and WMS-R yielded significant differences between patient groups and the two versions of the test. Patients with DAT made significantly more prior-figure intrusion errors than did HD patients on both versions of the VRT, but the original WMS form of this figural memory test was more likely to elicit such errors than was the revised version. Despite many improvements in the revised scale, a number of limitations still exist including standardization and a lack of norms for elderly individuals, as well as failures to include tests of verbal recognition and adequate measures of nonverbal memory.     

Priming effects and recognition memory in young and elderly adults

The present study explores the effects of age on the priming of alternate homophone spellings and recognition memory. Sixteen young and sixteen elderly adults were given a general information test, a spelling test, and a test of recognition memory. By embedding the less frequently spelled member of different homophone units (e.g., write vs. right) in the general information questions, certain of the homophones were primed during this task. The effect of this priming was assessed through the subjects' choice of spelling for these words on the spelling test. Recognition memory was assessed by asking subjects to indicate which words from a longer list were presented during the spelling test. As found in prior research priming effects were observed in younger subjects; however, no significant priming effects occurred in the older age group. On the recognition test, homophones were more often correctly recognized than nonhomophones, and priming affected the scores of the young negatively, but had no effects, positive or negative, on the elderly. These results suggest possible differences in the underlying bases of memory loss in aged adults and amnesics.     

Validity and reliability of auditory screening tests in demented and non-demented older adults

The validity and reliability of auditory screening tests were evaluated in 34 demented and 31 non-demented elderly outpatients. In reference to an audiometric gold standard (40-dB HL hearing loss in speech frequencies), 512-Hz and 1024-Hz tuning forks, finger rub, and whispered voice tests performed well (ROC curve areas = 0.82 to 0.94). Simultaneously high (greater than 0.80) sensitivities and specificities were achievable for all these tests in demented patients. In non-demented patients, however, only the whispered voice test achieved simultaneously high specificity and sensitivity. The most accurate rule for air conduction screening audiometry was the inability to hear greater than or equal to two of four 40-dB HL speech frequencies (sensitivity = 1.0, specificity = 0.75 in non-demented patients; sensitivity = 0.97, specificity = 0.74 in demented patients). Interobserver/test-retest reliability was generally high for tuning forks, finger rub, and whispered voice tests (range of intraclass correlation coefficients = 0.38 to 0.90), and was somewhat higher in demented than in non-demented patients. These results suggest that some of the simple, traditional methods of auditory screening may have considerable validity and reliability in demented and non-demented older adults.     

The short human figure drawing scale for evaluation of suspect cognitive dysfunction in old age

Human figure drawings have been widely used to assess cognitive development in children. In the present study, free-hand human figure drawings were examined for 62 demented patients, and 60 normal elderly subjects. The drawings were scored for 53 body details using a method derived from work with children. A short scale of 15 details was developed by selecting body details with high item-total correlations which are simple to score even for untrained staff. This short scale had excellent interscorer and test-retest reliability and excellent concurrent validity as well. It correlated highly with the Mini-Mental State Examination, a commonly used screening test for dementia. The short scale discriminated demented and non-demented subjects and different levels of dementia severity as graded by the Clinical Dementia Rating Scale. However, no differences were observed between Alzheimer patients and patients with vascular dementia concerning presence of details in human figure drawings.     

Memory performance in individuals with primary degenerative dementia: its similarity to diazepam-induced impairments

Impairments of memory storage and retrieval produced by diazepam (2.5 mg, 5 mg, and 10 mg) in normal elderly individuals were compared to those observed in patients with primary degenerative dementia tested under nondrug conditions. The highest diazepam dose affected retrieval as well as storage processes in Buschke's "selective reminding" task, producing impairments qualitatively similar to those shown by demented patients. All diazepam doses impaired Buschke task performance in the normal elderly individuals; normal young subjects, in contrast, showed no impairment with a low (2.5 mg) diazepam dose.     

Acquistion and retention of categorized material in normal aging and senile dementia

The “shopping list task” is a new verbal learning task with a high degree of face validity for elderly subjects. Learning and delayed recall performance were examined for three groups of subjects: young normals (n=63, median age=21), elderly normals (n=44, median age=69) and mild to moderately impaired senile dementia patients (n=60, median age=70). The young normal subjects performed best of the three groups in both initial learning and delayed recall measures. The elderly normals showed significant decrements in learning and recalling the list items (p<.01). The impaired elderly showed much greater performance decrements in both learning and recall. None of the subjects showed a deficit in delayed recognition. These results suggest that both storage and retrieval difficulties occur in normal aging and dementia. The recognition test results suggest that recall deficits evidenced by both elderly groups are in large part due to faulty retrieval mechanisms. Since the shopping list task discriminated well among the three groups, it has potential for memory assessment in clinical settings.     

CT study in dementia--today and in the future

The role of CT in the diagnosis of senile dementia of Alzheimer type (SDAT) is discussed. Research data show that, although SDAT is closely correlated with brain atrophy (sulcal and ventricular dilatation) there is a significant overlap with the normal elderly population: that is to say, within the demented population, CT changes correlate only weakly with cognitive impairment. However, taken together with other clinical indices, CT can be useful both for the assessment of SDAT and the exclusion of treatable lesions. Newer computer methods of analysis and technical improvements hold out hope for future clinical and research advances in this area.     

Orthostatic hypotension in Alzheimer's disease: result or cause of brain dysfunction?

In Alzheimer's disease (AD), an association was found between autonomic dysfunction and frontal hypoperfusion in brain during orthostatic testing. To ascertain whether frontal hypoperfusion is dependent on longitudinal effects of hemodynamic disturbances, or contributes to them, we studied the relationship between the presence of orthostatic hypotension (OH) and resting cerebral blood flow (CBF) in late stages of AD. Twelve women with senile dementia of Alzheimer type (SDAT), and 15 non-demented women (mean age 82.6 years, SD 3.8 vs 81.8 years, SD 3.5) were examined with the orthostatic test. Four of 12 patients with SDAT, and 9 controls had OH (defined as systolic blood pressure fall > or = 20 mmHg). CBF was determined under resting conditions using 600 Mbq 99mTc HMPAO single photon emission computerized tomography (SPECT), and quantified in cortical areas in relation to cerebellum. In patients with SDAT and OH, CBF was lower in frontal and parieto-frontal cortical areas than in SDAT patients without OH. The former group was younger and had a shorter dementia duration. No significant differences in CBF were observed between controls with vs without OH. No differences in SDAT patients with or without OH were observed in the Berger dementia scale or Katz' ADL index. No difference in incidence of symptoms related to autonomic disturbances (diarrhea, obstipation, dysphagia, vertigo) was observed in either the SDAT or control group with regard to OH presence. We conclude that during the course of AD, OH can contribute to frontal brain changes and may exacerbate the disease. The further involvement of frontal dysfunction in aggravating blood pressure dysregulation in the elderly is discussed.     

The problem of naming in SDAT: a relative deficit

Research relating to language disorder in senile dementia of the Alzheimer type (SDAT) has focused primarily on naming impairment, formally termed anomia or nominal aphasia/dysphasia. Data resulting from this research have been insufficiently informed by a comparative linguistic framework in which performance on naming tasks is contrasted with performance on other forms of language tasks. The present study involves the comparison of 21 adults with SDAT and 18 demographically controlled normal elderly adults on the Test for Syntactic Complexity and fifteen subtests of the Western Aphasia Battery. Performance on naming is compared with performance on oral language variables of repetition, yes/no response, auditory word recognition, sequential commands, syntactic processing, as well as with performance on reading tasks and non-verbal tasks. Findings relating to oral language tasks show that structured syntactic processing requiring explicit interpretation and sequential commands are significantly more difficult for the SDAT sample than are three of four naming tasks. Further, significant SDAT performance variability is found across naming tasks. The generative categorical naming task is found to be significantly more difficult for the SDAT patient than are the other three naming tasks. It is concluded that the generative categorical naming task should be regarded as a meta-naming task. In sum, it is found that although language dysfunction in SDAT has anomic components, the essential character of the language disorder is not best conceptualized as a problem of naming.     

Quantitative electroencephalography, with serial subtraction and odour detection in the differentiation of Alzheimer's disease and vascular dementia

The diagnosis of dementia can be difficult, yet diagnostic accuracy has important prognostic and therapeutic implications. Nevertheless, conventional electroencephalography (EEG) has always played a secondary role in dementia investigation. More recently quantitative EEG (qEEG) has allowed more detailed and objective analysis of EEG data, but there is still no clearly defined clinical role for qEEG. We have used relative power qEEG measures made during resting and active brain conditions (serial subtraction and odour detection tasks) to differentiate between demented and non-demented subjects, and between subjects with different forms of dementia. Electroencephalograms were obtained from 15 subjects with clinically diagnosed Alzheimer's disease (AD), 16 with a clinical diagnosis of vascular dementia (VaD), and 16 non-demented control subjects. Discriminate function analyses were used to differentiate groups according to task, electrode site, and frequency bandwidth. Correct classification, as demented or non-demented, was made for 93% of cases using qEEG comparisons of resting states with eyes closed and eyes opened. Almost all subjects with AD and VaD were correctly classified with qEEG recorded during odour detection (95%). qEEG for serial subtraction correctly classified AD and VaD in 91% of the dementia group. These results have important implications for future qEEG research, and may be pertinent to the precision of diagnosis in patients with dementia.     

Senile dementia of the Alzheimer's type: an important risk factor for serious falls

In a longitudinal study of senile dementia and healthy aging, the occurrence of serious falls was examined in participants with senile dementia of the Alzheimer's type (SDAT) (n = 44) and in cognitively healthy elderly control participants (n = 56) over a 4-year period. Falls occurred in 36% of SDAT individuals versus 11% of controls. The higher frequency of falls in demented participants was not explained by greater neurologic deficit nor by increased drug use compared with controls. However, males with SDAT who reported falls, had higher mean blood pressures and were more likely to be medicated than males with SDAT who did not fall. These differences were not observed in women. Falls in SDAT participants were associated with an increased rate of institutionalization. SDAT is an important risk factor for serious falls, and falls are associated with loss of independence in demented patients.     

The problem of naming in SDAT: A relative deficit

Abstract

Research relating to language disorder in senile dementia of the Alzheimer type (SDAT) has focused primarily on naming impairment, formally termed anomia or nominal aphasia/dysphasia. Data resulting from this research have been insufficiently informed by a comparative linguistic framework in which performance on naming tasks is contrasted with performance on other forms of language tasks. The present study involves the comparison of 21 adults with SDAT and 18 demographically controlled normal elderly adults on the Test for Syntactic Complexity and fifteen subtests of the Western Aphasia Battery. Performance on naming is compared with performance on oral language variables of repetition, yes/no response, auditory word recognition, sequential commands, syntactic processing, as well as with performance on reading tasks and non-verbal tasks. Findings relating to oral language tasks show that structured syntactic processing requiring explicit interpretation and sequential commands are significantly more difficult for the SDAT sample than are three of four naming tasks. Further, significant SDAT performance variability is found across naming tasks. The generative categorical naming task is found to be significantly more difficult for the SDAT patient than are the other three naming tasks. It is concluded that the generative categorical naming task should be regarded as a meta-naming task. In sum, it is found that although language dysfunction in SDAT has anomic components, the essential character of the language disorder is not best conceptualized as a problem of naming.     

TRANSIENT IMPROVEMENT OF MEMORY IN SENILE DEMENTIA FOLLOWING MNEMONIC TRAINING

The effect of Levodopa administration and mnemonic strategy training in the treatment of memory deficits associated with denile dementia of the Alzheimer type was investigated in a short-term longitudinal study. Levodopa administration exerted no significant effect upon memory functioning whereas training in the chunking of information and in visual association led to a significant, but temporary, improvement in memory functioning. Training raised performance of demented subjects to about 58% of that of non-demented controls, compared to the 38% observed at baseline. No significant interactions between the drug and training manipulation were indicated.     

Age‐related change in visual,spatial and verbal memory

Objectives: To explore the relationship between age and performance on verbal, visual and spatial memory tasks and to examine whether verbal, visual and spatial memory can be measured as separate memory representations. Methods: Sixty‐two participants aged between 18 and 57 years completed a listening span task, a dot memory task and an irregular polygon with articulatory suppression task. Results: Verbal and spatial memory declined with increased age. The relationship between age and visual memory, although negative, was not significant. Age correlated with verbal memory to a greater degree than with visual or spatial memory. The correlations between each of the memory tasks were not significant, suggesting that each task was tapping a distinct type of memory. Conclusions: Verbal, visual and spatial memory appear to be differentially affected by age and should be examined as separate representations.     

Influence of age and illness on color preference

Color preference was evaluated in 14 non-demented end 10 demented (Alzheimer’s disease) elderly residents of a skilled nursing facility. whereas blue (480 mu) was the color most preferred by the non-demented subjects, green (525 mu) was that color most preferred by those with dementia. In addition to reporting study results, factors capable of Influencing color selection are discussed. Health planners should consider preferences for environmental colors, especially for institutionalized persons incapable of changing their own environment.