Apathy and executive function in Alzheimer's disease

Abstract

Apathy is a common behavioral disturbance in patients with Alzheimer's disease (AD). Recent studies have linked the presence of apathy to alterations in frontal lobe functions, but few studies have explored the relationship using standard neuropsychological measures in patients with AD. We administered a comprehensive battery of neuropsychological tests and a behavior rating scale to 80 patients with AD. We explored the relationship of apathy to executive dysfunction. AD patients with apathy performed significantly worse on tests of executive function (WAIS-R Digit Symbol, Trail-Making, Stroop Color Interference Test) than AD patients without apathy. The presence of dysphoria did not modify these results and no significant relationships were found between tests of executive functions and dysphoria. Performance on executive measures as a group were effective in correctly classifying patients as apathetic or nonapathetic with 75% accuracy. Neuropsychological measures not dependent on executive functions were unrelated to apathy. Apathy is associated with executive dysfunction and not with other neuropsychological deficits. Apathy is distinct from dysphoria. (JINS, 2002, 8, 373-381.)

A Novel Assessment and Profiling of Multidimensional Apathy in Alzheimer’s Disease

“…As one of the most prominent behavioral symptoms in AD, cognitive impairment is also associated with apathy [45][46][47]. While memory impairment is common in AD, attention [48] and executive dysfunction [49], such as planning, spatial navigation attention [50][51][52] and verbal fluency [53] are also particularly noted to be impaired as the disease progresses to later stages, which is particularly relevant to our sample which is more impaired. However, it is important to differentiate between the DAS Executive apathy items and executive functioning assessments, wherein the overt, observational assessments of the former and the performance-based assessment of the latter, are unlikely to fully overlap but are more likely to measure similar elements relating to demotivation towards planning, organization and attention.…”

Neurobiology of apathy in Alzheimer's disease

“…The neuropsychological profile of apathetic patients with McI who have converted to Ad gives interesting insight into the neuroanatomy of apathy. robert and colleagues showed that an apathetic McI group performed significantly worse in free recall memory tests, without concomitant deficits in other tests of executive functions 31 , in contrast with previous evidence from more advanced demented patients 30 . we believe that an executive default in activating strategies for retrieval from episodic memory might be a suitable explanation for these findings.…”

“…The typical apathetic patient usually lacks the negative thoughts, sadness and somatic complaints frequently observed in mood disorders 22 . Furthermore, apathy has been associated with extrapyramidal signs 29 and neuropsychological deficits which cannot be explained by depressive symptoms 30,31 .…”

Apathy and Executive Dysfunction in Alzheimer Disease

“…McPherson et al 8 showed that apathy in AD was significantly associated with poor performance on executive function tests, such as the Trail-Making Test and the Stroop color interference test. In addition, a study by Robert et al 9 showed that apathy in AD was significantly related to a divided attention impairment observed in the dual-task procedure developed by Baddeley et al 10 More recently, Tsoi et al 11 showed that an executive dysfunction, especially deficits affecting verbal fluency (number of animals named in 1 min) and ideational fluency (unusual uses for a bottle), was a significant predictor of apathy in dementia.…”