ABSTRACT
Although Frontotemporal Dementia (FTD) is the second most common form of dementia after Alzheimer's disease, its diagnosis remains particularly challenging today. This is particularly true for the behavioral variant (bvFTD), the most common phenotype of FTD, which is characterised by dramatic changes in personal and social conduct. Novel clinical cognitive tests have been recently proposed to diagnose and assess these patients. Among them, the mini-SEA (Social cognition & Emotional Assessment) has shown promising results. This quick clinical tool evaluates emotion recognition and theory of mind deficits, both recognized as hallmark features of bvFTD. In this study, we investigated the neural correlates of the mini-SEA in twenty bvFTD patients, using single photon emission computed tomography (SPECT) and focusing on the mPFC. Results showed that detection of faux pas during a theory of mind evaluation was related to rostral mPFC perfusion (BA 10) while recognition of emotion involved more dorsal regions within the mPFC (BA 9). As significant and early dysfunction of the mPFC has been extensively described in bvFTD, this study supports the use of the mini-SEA in evaluation and diagnosis purposes in bvFTD.
Subject(s)
Frontotemporal Dementia/diagnosis , Frontotemporal Dementia/physiopathology , Prefrontal Cortex/physiopathology , Psychological Tests , Aged , Aged, 80 and over , Brain Mapping , Emotions/physiology , Female , Frontotemporal Dementia/diagnostic imaging , Humans , Male , Middle Aged , Neuropsychological Tests , Phenotype , Prefrontal Cortex/diagnostic imaging , Recognition, Psychology/physiology , Theory of Mind/physiology , Tomography, Emission-Computed, Single-PhotonABSTRACT
BACKGROUND: Long term effects of subthalamic nucleus (STN) stimulation on cognition, mood, and behaviour are unknown. OBJECTIVE: This study evaluated the cognitive, mood, and behavioural effects of bilateral subthalamic nucleus deep brain stimulation (STN DBS) in patients with Parkinson's disease (PD) followed up for three years. METHODS: A consecutive series of 77 PD patients was assessed before, one, and three years after surgery. Mean (SD) age at surgery was 55 (8). Seven patients died or were lost for follow up. Neuropsychological assessment included a global cognitive scale, memory, and frontal tests. Depression was evaluated using the Beck depression inventory. Assessment of thought disorders and apathy was based on the unified Parkinson's disease rating scale. Reports of the behavioural changes are mainly based on interviews done by the same neuropsychologist at each follow up. RESULTS: Only two cognitive variables worsened (category fluency, total score of fluency). Age was a predictor of decline in executive functions. Depression improved whereas apathy and thought disorders worsened. Major behavioural changes were two transient aggressive impulsive episodes, one suicide, four suicide attempts, one permanent apathy, one transient severe depression, four psychoses (one permanent), and five hypomania (one permanent). CONCLUSIONS: Comparing baseline, one year, and three year postoperative assessments, STN stimulation did not lead to global cognitive deterioration. Apathy scores mildly increased. Depression scores mildly improved. Behavioural changes were comparatively rare and mostly transient. Single case reports show the major synergistic effects of both medication and stimulation on mood and behaviour, illustrating the importance of a correct postoperative management.
