AbstractBackgroundApathy is a common neuropsychiatric symptom in Neurocognitive Disorders (NCD). It is characterized by a significant reduction of goal‐directed behaviors in the domains of cognition, behavior, emotions, and social interactions. Goal‐directed behaviors can be investigated using effort‐based decision paradigms, allowing computational models to quantify sensitivity to effort and reward (and their combination) in a systematic way [1]. Our study used an effort‐based decision paradigm to investigate apathetic symptoms in a clinical context with older people with NCD and subjective cognitive decline (SCD).MethodWe recruited 33 participants with mild NCD or SCD from the Memory Center in Nice (24 females, mean age= 74 years, mean MMSE score = 27.1). We assessed self‐reported apathy using the Apathy Motivation Index (AMI) and the Dimensional Apathy Scale (DAS). We also assessed self‐reported fatigue (Multidimensional Fatigue Inventory, MFI), anhedonia (Snaith‐Hamilton Pleasure Scale, SHAPS), and depression (Geriatric Depression Scale, GDS). The effort‐based decision task consisted of choosing to perform an action (taping as quickly as possible on a tactile tablet to fill a virtual pool corresponding to 25%, 50%, 75% and 100% of the maximum individual effort) to obtain a specific reward (3, 6 or 9 credits to discover pictures), or to rest to ensure 1 credit. For each subject, we extracted a parameter (K) representing the degree to which a reward is devalued by effort.ResultsWe divided participants into two groups with high and low AMI scores using a mean split. Results suggested that the K‐parameter was almost significantly lower in subjects with higher apathy (U=86, p=0,072). Further and more detailed analyses will be performed once reached a sample size of 50 subjects (end of June 2021).ConclusionsEffort‐based decision tasks may be employed also in people with NCD, and may help to differentiate patients with low and high apathy. The study is ongoing, and a bigger sample will allow to better characterize these results. Reference: [1] Lockwood, P., Hamonet, M., Zhang, S. et al. Prosocial apathy for helping others when effort is required. Nat Hum Behav. 1, 0131 (2017). https://doi.org/10.1038/s41562‐017‐0131
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