ABSTRACT
We examined script representation in 26 patients with Alzheimer's disease (AD) compared to 31 healthy elderly subjects (HE). Participants were asked to sort cards describing actions belonging to eight scripts according to the script to which they belonged and according to their order of execution. Each script included actions which were low in centrality and distinctiveness (non-central actions and non-distinctive actions--NCA & NDA), and which were high in centrality (central actions--CA), distinctiveness (distinctive actions--DA), centrality and distinctiveness (central actions and distinctive action--CA & DA). These actions were presented in three conditions. In the first condition (scripts with headers--SH), the 43 actions belonging to three different scripts were given with each script header written on separate cards. The second condition (scripts without headers--SwH) used 46 actions belonging to three other scripts, but no script header was provided. In the third condition (scripts with distractor header--SDH), the 28 actions belonging to two other scripts were given with each script header and a distractor header written on separate cards. The results showed that performance of subjects with AD was significantly lower in all conditions. Overall, AD patients made significantly more sequencing errors than HE subjects. AD patients also committed significantly more sorting errors than HE subjects for all types of actions (NCA & NDA, CA, DA, CA & DA). These data are consistent with the view that AD produces impairment of both the syntactic and semantic dimensions of script representation.
Subject(s)
Alzheimer Disease/psychology , Discrimination, Psychological/physiology , Pattern Recognition, Physiological/physiology , Problem Solving/physiology , Serial Learning/physiology , Activities of Daily Living , Aged , Alzheimer Disease/physiopathology , Case-Control Studies , Concept Formation/physiology , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Reference Values , Severity of Illness IndexABSTRACT
Creutzfeldt-Jakob disease (CJD) is the most frequent transmissible spongiform encephalopathy. Its definite diagnosis is ascertained by cerebral neuropathological exam. However, diagnosis of a probable or possible case of CJD can be evoked on the basis of Masters'classification which is based on the association of different clinical and electroencephalographical criteria. We report the case of a 58-year-old woman who died in a geriatric unit of autopsy proven sporadic CJD. The clinical course over 15 months was rapidly progressive dementia without characteristic clinical and EEG signs. The case presentation did not meet the criteria of probable or possible CJD, according to Masters'classification. However, 4 months after the onset of the disease, t-Flair MRI revealed an increased signal intensity in the right frontal and occipital cortex which could suggest the diagnosis of CJD. This case therefore stresses the contribution of MRI, especially diffusion-weighted imaging, for early diagnosis of CJD. It shows also the short comings of Masters'classification which does not always enable diagnosis of CJD even though control measures would have to be rapidly undertaken, specially the decontamination of medico-surgical equipment. Finally, this case illustrates the great importance of post mortem exam in such context. In light of this clinical observation, we discuss this rare diagnosis which should be considered in geriatrics when confronted with a rapidly progressive dementia
