Nonverbal Memory Tasks in Early Differential Diagnosis of Alzheimer's Disease and Unipolar Depression

Abstract

We examined whether there are selective deficits in early-stage Alzheimer's disease (AD; n = 27) and in unipolar depression (UD; n = 17) patients on recall and recognition of spatial and visual components of nonverbal memory (NVM) and whether the two groups can be differentiated based on their performance on such tasks. We also investigated which NVM measures had the best discrimination power. We tested spatial, visuospatial, and visuoconstructive abilities in AD and UD patients. AD patients' scores on NVM tasks were significantly lower than those of healthy subjects (HS; n = 30) and consistently lower than those of the UD group. Z-scores suggested that AD patients suffered from a generalized impairment. Clear differences between AD and UD patients were found on abstract design tasks.

The Mini-Mental-37 Test for Dementia Screening in the Spanish Population: An Analysis Using the Rasch Model

“…For example, calculation can be particularly difficult for persons with a low level of formal education, and 75% of our sample had not completed primary education. Meanwhile, memory tasks are particularly sensitive to aging and other common conditions in the population such as mild cognitive impairment (Contador & Ramos, 2009;Salthouse, 2004), which probably reduce its discrimination power. On the other hand, naming is a simple task, with a high likelihood of correct response even in persons with dementia.…”

“…Finally, we are aware that dementia is a cognitive heterogeneous syndrome (Contador & Ramos, 2009), but sample sizes requisites of Rasch PCM makes it very difficult to get enough clinical cases according to dementia subtypes (Linacre, 2002). Screening for dementia in the population requires simple and useful instruments that can help us detect the presence of cognitive decline (Mitchell & Malladi, 2010).…”

Spanish version of the Mattis Dementia Rating Scale‐2 for early detection of Alzheimer's disease and mild cognitive impairment

“…The ME subscale best discriminated between all three groups, obtaining a better diagnostic accuracy than the global scale. The superiority of both subscales (ME and I/P) over the rest of the MDRS‐2 subtests confirms previous findings in people with AD (Chan et al ., ; Miller and Pliskin, ; Rascovsky et al ., ), providing further evidence for deficits in episodic memory and executive functions as distinctive features in early AD (Bondi et al ., ; Contador et al ., ; Martyr and Clare, ).…”

“…Cognitive markers have proven to be more reliable predictors of conversion from mild cognitive impairment (MCI) to AD than most biomarkers (Gomar et al, 2011), especially when the time of conversion is longer than 18 months (Egli et al, 2014). Episodic memory is one of the first markers to become abnormal (Contador et al, 2010a;Jedynak et al, 2012), sometimes up to 10.5 years before the clinical diagnosis of AD (Mistridis et al, 2015).…”

Cognitive Impairment in Late-Life Depression: A Comparative Study of Healthy Older People, Late-Life Depression, and Mild Alzheimer's Disease Using Multivariate Base Rates of Low Scores

“…They are not surprising and consistent with previous studies reported that memory tasks have relatively high power to discriminate AD and older depressed patients. However, these studies have focused on a single or overall cognitive composite score and were carried out in small samples size which could result in a probable lack of statistical power (Swainson et al, 2001 ; Foldi et al, 2003 ; Künig et al, 2006 ; Dierckx et al, 2007 , 2011 ; Federico et al, 2008 ; Contador et al, 2010 ; Para et al, 2010 ; Croisile et al, 2011 ; Mazur-Mosiewicz et al, 2011 ; Rotomskis et al, 2015 ).…”