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ABSTRACT: BACKGROUND: The aim of this study was to compare the utility and diagnostic accuracy of the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) in the diagnosis of Alzheimer's disease (AD) and mild cognitive impairment (MCI) in a clinical cohort. METHODS: Three hundred twenty-one AD, 126 MCI, and 140 older adults with healthy cognition (HC) were evaluated using the MMSE, the MoCA, a standardized neuropsychologic battery according to the Consortium to Establish a Registry of Alzheimer's Disease (CERAD-NB), and an informant-based measure of functional impairment, the Dementia Severity Rating Scale (DSRS). Diagnostic accuracy and optimal cut-off scores were calculated for each measure, and a method for converting MoCA to MMSE scores is presented. RESULTS: The MMSE and MoCA offer reasonably good diagnostic and classification accuracy as compared with the more detailed CERAD-NB; however, as a brief cognitive screening measure, the MoCA was more sensitive and had higher classification accuracy for differentiating MCI from HC. Complementing the MMSE or the MoCA with the DSRS significantly improved diagnostic accuracy. CONCLUSION: The findings support recent data indicating that the MoCA is superior to the MMSE as a global assessment tool, particularly in discerning earlier stages of cognitive decline. In addition, we found that overall diagnostic accuracy improves when the MMSE or MoCA is combined with an informant-based functional measure. Finally, we provide a reliable and easy conversion of MoCA to MMSE scores. However, the need for MCI-specific measures is still needed to increase the diagnostic specificity between AD and MCI.
Alzheimer's & dementia: the journal of the Alzheimer's Association 12/2012; · 5.90 Impact Factor
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ABSTRACT: BACKGROUND: White matter alterations in schizophrenia are associated with deficits in neurocognitive performance. Recently, across task within-individual variability (WIV) has emerged as a useful construct for assessing the profile in cognitive performance in schizophrenia. However, the neural basis of WIV has not been studied in patients with schizophrenia. METHODS: Twenty-five patients with schizophrenia (SZ) and 27 healthy comparison subjects (HC) performed a computerized neurocognitive battery (CNB) and underwent diffusion tensor imaging (DTI). WIV for performance accuracy and speed on the CNB was calculated across-tasks. Voxel-wise group comparisons of white matter fractional anisotropy (FA) were performed using tract-based spatial statistics (TBSS). The relationship between accuracy and speed WIV on the CNB and white matter FA was examined within the regions that differentiated patients and healthy comparison subjects. RESULTS: SZ had higher WIV for performance accuracy and speed as compared to HC. FA in SZ compared to HC was reduced in bilateral frontal, temporal and occipital white matter including a large portion of the corpus callosum. In white matter regions that differed between patients and comparison subjects, higher FA in the left cingulum bundle and left fronto-occipital fasciculus were associated with lower CNB speed WIV for HC, but not SZ. Accuracy WIV was not associated with differences in white matter FA between SZ and HC. CONCLUSIONS: We provide evidence that WIV is greater in patients with SZ and that this greater within-individual variability in performance in patients is associated with disruptions of WM integrity in specific brain regions.
Biological Psychiatry 11/2012; · 8.28 Impact Factor
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ABSTRACT: Certain cognitive measures are heritable and differentiate individuals at risk for schizophrenia from unaffected family members and healthy comparison subjects. These deficits in neurocognitive performance in patients with schizophrenia appear stable in the short-term. However, the duration of most, but not all, longitudinal studies is modest and the majority have relied on traditional average performance measures to examine stability. Using a computerized neurocognitive battery (CNB), we assessed mean performance (accuracy and speed) and intra-individual variability (IIV) in a longitudinal study aimed to examine neurocognitive stability in European-American multiplex families with schizophrenia. Thirty-four patients with schizophrenia, 65 unaffected relatives, and 45 healthy comparison subjects completed the same computerized neurocognitive assessment over approximately 5 years. Measures of mean performance showed that patients had stable accuracy performance but were slower in many neurocognitive domains over time as compared with unaffected family members and healthy subjects. Furthermore, patients and family members showed dissociable patterns of change in IIV for speed across cognitive domains: compared with controls, patients showed higher across-task IIV in performance compared with family members, who showed lower across-task IIV. Patients showed an increase in IIV over time, whereas family members showed a decrease. These findings suggest that measures of mean performance and IIV of speed during a CNB may provide useful information about the genetic susceptibility in schizophrenia.
Schizophrenia Bulletin 08/2012; · 8.80 Impact Factor
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ABSTRACT: Older adults' decision quality is considered to be worse than that of younger adults. This age-related difference is often attributed to reductions in risk tolerance. Little is known about the circumstances that affect older adults' decisions and whether risk attitudes directly influence economic decisions. We measure the influence of risk attitudes on age-related differences in decision making in both nonsocial and social contexts.
Risk attitudes and economic decision making were measured in 30 healthy older adults and 29 healthy younger adults.
Older adults report being less impulsive, sensation seeking and risk tolerant than younger adults. Age did not affect a measure of nonsocial economic decision making. Older adults were more likely to reject unfair divisions of money during an economic social-bargaining game and more likely to make equitable divisions of money during social-giving game. These age-related differences were determined in part by individuals' self-reported risk taking.
We conclude that age-related differences in decision making are domain specific and that some social economic decision making is influenced by risk attitudes. Older adults are more risk avoidant, but this does not alter their willingness to wait for reward in a nonsocial context. Perceiving more risk is associated with an unwillingness to accept an unfair offer in social economic contexts and ultimately leads to poorer outcomes for older adults.
The Journals of Gerontology Series B Psychological Sciences and Social Sciences 09/2011; 67(3):289-98. · 2.62 Impact Factor
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ABSTRACT: Several recent studies have documented age-related changes in brain activity--less amygdala activity and higher prefrontal activity in response to emotional stimuli. Using functional magnetic resonance imaging (fMRI), we examined whether aging also affects the maintenance of activity to emotional stimuli and whether maintenance differs by the valence (negative, neutral and positive) of the pictures. Younger participants had a larger volume of activity in the amygdala but less in the prefrontal cortex than the old. The old showed more habituation to highly arousing negative but not positive or neutral stimuli in prefrontal cortex as compared to younger participants. Thus prefrontal cortex activity indexes emotion in the elderly, but not the young. Amplified prefrontal activity suggests elderly increase cognitive control for negative, highly arousing emotional stimuli, but it is not maintained. Taken together, age-related increases in prefrontal activity and reduced amygdala activity may underlie observed affective changes in aging.
Neurobiology of aging 11/2009; 32(9):1634-50. · 5.94 Impact Factor
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ABSTRACT: To examine phenylthiocarbamide (PTC) sensitivity in Parkinson disease (PD) patients and healthy volunteers to determine whether taster status represented a simple vulnerability marker for PD.
The inability to taste PTC has been associated with a number of medical illnesses not typically associated with taste impairment. Abnormalities in the function/expression of G protein-signaling pathways have been implicated in PTC perception and also in dopamine expression and regulation in PD. No study has yet probed whether PTC tasting is disrupted in PD.
PTC sensitivity was assessed in a small sample of 36 male PD patients and 20 healthy male comparison subjects using a standardized psychophysical method.
A higher proportion of nontasters were found in patients relative to healthy comparison subjects. These differences were not explained by alterations in perception of basic taste intensity or age. Among patients, nontasters and tasters of PTC did not differ with regard to duration of illness, age of onset, severity of motor symptoms, or overall illness severity.
These data suggest an increase in the frequency of PTC nontaster status in PD. As phenotypic variation in PTC sensitivity is genetic in origin, this may represent a surrogate risk factor for the development of PD.
Cognitive and Behavioral Neurology 10/2007; 20(3):145-8. · 1.34 Impact Factor
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ABSTRACT: The inability to taste phenylthiocarbamide (PTC; "taste-blindness") has been associated with a number of medical and neurological illnesses not typically related to taste. We examined PTC sensitivity in 67 schizophrenia patients, 30 healthy controls, and 30 first-degree relatives to determine whether taster status could represent a simple vulnerability marker. A higher prevalence of non-tasters was seen in patients and family members relative to healthy controls. Among patients, non-tasters exhibited increased levels of negative and first-rank symptoms as well as poorer right nostril odor identification skills relative to PTC tasters. These differences were not explained by age, sex, education, smoking, or intensity differences. Phenotypic variation in PTC sensitivity is thought to be genetic in origin and suggests greater illness risk for those subjects with recessive taster alleles.
Schizophrenia Research 03/2007; 90(1-3):221-8. · 4.75 Impact Factor
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Paul J Moberg,
Steven E Arnold,
Richard L Doty,
Raquel E Gur,
Catherine C Balderston, David R Roalf,
Ruben C Gur,
Christian G Kohler,
Stephen J Kanes,
Steven J Siegel,
Bruce I Turetsky
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ABSTRACT: Deficits in odor identification and detection threshold sensitivity have been observed in schizophrenia but their relationship to clinical, cognitive, and biologic measures have not been clearly established. Our objectives were to examine the relationship between measures of odor identification and detection threshold sensitivity and clinical, neuropsychological, and anatomic brain measures. Twenty-one patients with schizophrenia and 20 healthy controls were administered psychophysical tests of odor identification and detection threshold sensitivity to phenyl ethyl alcohol. In addition, clinical symptom ratings, neuropsychological measures of frontal and temporal lobe function and whole brain MRIs were concurrently obtained. Patients exhibited significant deficits in odor identification but normal detection threshold sensitivity. Poorer odor identification scores were associated with longer duration of illness, increased negative and disorganized symptoms, and the deficit syndrome, as well as impairments in verbal and nonverbal memory. Better odor detection thresholds were specifically associated with first-rank or productive symptoms. Larger left temporal lobe volumes with MRI were associated with better odor identification in controls but not in patients. Given the relevance of the neural substrate, and the evidence of performance deficits, psychophysical probes of the integrity of the olfactory system hold special promise for illuminating aspects of the neurobiology underlying schizophrenia.
Journal of Clinical and Experimental Neuropsychology 12/2006; 28(8):1444-61. · 2.13 Impact Factor
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ABSTRACT: The authors examined Apolipoprotein E (ApoE) genotype frequencies and unirhinal odor identification in 28 schizophrenia patients and 26 healthy comparison subjects. No significant associations between ApoE status and olfaction were observed in either diagnostic group. The authors concluded that olfactory deficits in schizophrenia do not appear to be mediated by the ApoE allele.
Journal of Neuropsychiatry 02/2006; 18(2):231-3. · 2.51 Impact Factor
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ABSTRACT: Previous studies report birhinal impairments in odor identification in patients with schizophrenia and their family members. The authors employed unirhinal odor identification and detection threshold sensitivity tests in schizophrenia patients, healthy first-degree family members, and healthy comparison subjects. Patients and family members showed deficits in odor identification performance in both nostrils. Odor detection thresholds differed only between patients and healthy comparison subjects. Comparable odor identification deficits in both patients and healthy family members suggest that odor identification measures may serve as a sensitive endophenotypic vulnerability marker and that unirhinal olfactory measures are as precise, if not more so, than birhinal performance measures.
Journal of Neuropsychiatry 02/2006; 18(3):389-96. · 2.51 Impact Factor
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ABSTRACT: The inability to taste phenylthiocarbamide (PTC) has been associated with medical and neurological illnesses not typically related to taste. The authors examined PTC sensitivity in schizophrenia patients and their non-ill relatives to determine whether this represented a vulnerability marker.
PTC sensitivity was assessed in 42 schizophrenia patients, 23 healthy comparison subjects, and 12 first-degree relatives of the patients.
More nontasters were found among patients and family members than healthy comparison subjects. Among patients, nontasters had more positive symptoms. Differences were not explained by sex, age, medication, smoking, or cognitive impairment.
The prevalence of PTC nontasters was greater among schizophrenia patients and non-ill first-degree family members. Phenotypic variation in PTC sensitivity is genetic in origin. This suggests a higher risk for illness among subjects with recessive alleles.
American Journal of Psychiatry 05/2005; 162(4):788-90. · 12.54 Impact Factor
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ABSTRACT: Anatomical and functional deficits of the olfactory neural system have been identified in patients with schizophrenia. Since olfactory structures develop in conjunction with both the palate and ventral forebrain, the authors hypothesized that schizophrenia patients might have structural abnormalities of the nasal cavity, which could represent specific markers of embryological dysmorphogenesis underlying schizophrenia.
A measurement of nasal volume was acquired by acoustic rhinometry for 40 male schizophrenia patients and 24 healthy male comparison subjects.
The patients had smaller posterior nasal volumes than the comparison subjects but did not differ in anterior nasal volumes. This difference persisted after covarying for height and smoking history.
The lower observed posterior nasal volume likely reflects a specific developmental craniofacial abnormality. This finding confirms an early disruption in embryological development in males with schizophrenia and may represent a genetic or environmental "first hit" that leaves the individual vulnerable to subsequent pathology.
American Journal of Psychiatry 01/2005; 161(12):2314-6. · 12.54 Impact Factor
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ABSTRACT: Patients with schizophrenia exhibit olfactory deficits, but it is unclear whether these represent a specific abnormality. The link between olfactory impairments and regional brain abnormalities has yet to be established.
To determine whether patients with schizophrenia exhibit volumetric deficits in the anterior ventromedial temporal lobe, the target for neuronal inputs from the olfactory bulb, and whether these are related to olfactory performance deficits.
A cohort study of patients and healthy control subjects who underwent both 1-mm spoiled-gradient echo magnetic resonance imaging and behavioral tests of olfaction and memory.
Schizophrenia Research Center at the University of Pennsylvania, Philadelphia.
Fifty-two patients with a DSM-IV diagnosis of schizophrenia and 38 healthy control subjects. Individuals were excluded for history of head trauma, significant substance abuse, and medical conditions affecting brain function or olfactory capacity.
Gray matter volumes of the left and right temporal poles and the perirhinal and entorhinal cortexes; olfactory threshold detection sensitivity and identification test scores; composite indexes of verbal and spatial memory ability.
Patients had reduced volumes, relative to cranial size, in left (P =.003) and right (P =.01) perirhinal and left (P =.002) and right (P =.002) entorhinal cortexes, but not in the temporal pole. Perirhinal, but not entorhinal, cortical volume decrement was associated with decreased olfactory threshold sensitivity. Neither region was associated with impaired memory performance.
Patients with schizophrenia have reduced cortical volumes in brain regions that receive afferents directly from the olfactory bulb. Behavioral olfactory deficits are related to structural brain abnormalities in these regions.
Archives of General Psychiatry 01/2004; 60(12):1193-200. · 12.02 Impact Factor
