Alzheimer Disease, Mixed Dementias, Vascular Dementia
Conditions
Keywords
Working memory, Alzheimer disease, Vascular dementia, Mixed dementia, Complex span task
Brief summary
The aim of the present study is to investigate potential cognitive mechanisms contributing to working memory impairment in Alzheimer's disease and vascular dementia. The investigators consider a new hypothesis suggesting that difficulties in mobilizing maintenance strategies of information could explain this working memory deficit. More specifically, the investigators assume that patient groups will have difficulties in employing both refreshing and elaborative strategies during a working memory task (i.e., complex span task), as compared to a control group.
Detailed description
Working memory is considered as a central hub in human cognition. Good working memory capacities are fundamental for daily life. However, previous research has indicated that patients with Alzheimer's disease or vascular dementia have significant working memory impairment. Currently, there is no consensus on the cognitive mechanisms responsible for this deficit. Prior findings have highlighted that patients with Alzheimer's disease and/or vascular dementia demonstrate specific difficulties in dual-task situations. In this context, the investigators hypothesize that the continuous alternation between maintenance and processing phases involved in working memory could be impaired for these patients. Thus, the aim of the present study is to investigate if patients with Alzheimer's disease and/or vascular dementia can use maintenance strategies of information in working memory, as typically observed in individuals without cognitive impairments. To this end, the investigators propose a short working memory task in which they manipulate the opportunities to use refreshing strategies and elaborative strategies. The investigators expect that patients with Alzheimer's disease, vascular dementia, or mixed dementia will benefit less than healthy older adults from the increased opportunities to employ refreshing and elaboration. These difficulties could account for the impaired working memory performance associated with these diseases. In a second step, the investigators formulate distinctive hypotheses between patient sub-groups: * On the one hand, Alzheimer's disease is characterized by salient impairment of episodic long-term memory. Consequently, the investigators hypothesize that the working memory decline could be related to this deficit in long-term memory. Specifically, patients with Alzheimer's disease would have greater difficulty in implementing elaboration strategies. Thus, these patients' recall performance should benefit less from semantic links between the to-be-remembered items compared to patients with vascular dementia. * On the other hand, vascular dementia is characterized by a significant impairment of executive functioning. Thus, the investigators hypothesize that the working memory decline could be related to difficulties in implementing refreshing strategies (i.e., voluntary control of attention). Thus, the recall performance of these patients should benefit less from increased free time during the task, compared to patients with Alzheimer's disease. * Finally, very few studies have been carried out on patients with mixed dementia (from both Alzheimer's disease and vascular dementia). The investigators assume that the recall performance of these patients will benefit less from elaborative opportunities compared to patients with dementia vascular, and less from refreshing opportunities compared to patients with Alzheimer's disease.
Interventions
BEHAVIORALComplex span task
The intervention consists in a computerized working memory task. This task follows the design of a complex span task, involving alternation between memorization and processing steps. For each trial, participants have to memorize French words. These words are sequentially displayed on the screen. Between each word, participants perform a processing task consisting in a spatial location task: They have to determine if a shape is at the top or at the bottom of the screen. After each processing episode, participants have a free time (i.e., available time to maintain information in WM). At the end of each trial, participants perform an orally immediate recall. This experimental task involves several conditions in order to manipulate the opportunities for the spontaneous use of refreshing and elaborative strategies.
DIAGNOSTIC_TESTClinical neuropsychological assessment
As part of routine care, participants in the patient group undergo a standardized clinical neuropsychological assessment that evaluates several cognitive functions. The investigators hypothesize correlations between working memory performance during the experimental task and the results of neuropsychological tests. Thus, the investigators consider the results to several French versions of neuropsychological tests: * MMSE (Mini-Mental State Examination) * Digit Span Backward subtest (WAIS-IV) * Stroop Test * Trail Making Test (TMT) * Rappel Libre - Rappel Indicé à 16 items or GERIA-12 * Category fluences * Instrumental Activities of Daily Living and ADL .
DIAGNOSTIC_TESTClinical neurospychological assessement
Participants in the control group undergo 2 tests clinical that evaluate cognitive functioning. The investigators consider the results to French versions of these neuropsychological tests: * MMSE (Mini-Mental State Examination; ) * Digit Span Backward subtest (WAIS-IV)
Sponsors
University Grenoble Alps
Université Savoie Mont Blanc
Centre National de la Recherche Scientifique, France
Laboratoire de Psychologie et NeuroCognition
University Hospital, Grenoble
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
65 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* For patient and control groups: Adults ≥ 65 years of age * For patient and control groups: Native French speaker * For patient and control groups: Vision for easy reading * For patient and control groups: Hearing for easy instruction understanding * For patient and control groups: Back span ≥ 3 during the Digit Span Backward subtest (WAIS-IV) * For patient and control groups: Formulation of the non-opposition to participate in this study * For patient group only: Consultation in Grenoble University Hospital (Centre de Gérontologie Sud - Gerontology center) for clinical neuropsychological assessment due to suspected cognitive impairment * For patient group only: Diagnosis of Alzheimer's disease, vascular dementia, or mixed dementia (i.e., Alzheimer's disease and vascular dementia) * For patient group only: Have undergone a neuropsychological assessment at the day clinic, less than 6 months old. * For patient group only: Have obtained a medical opinion stating that there is no contraindication to participate in this study and no concurrent pathology that could impair the patient's cognitive abilities. * For patient group only: Absence of praxis and language disorders thath might prevent the carrying out of the experimental task. * For patient group only: MMSE score between 18 and 25 included * For control group only: External visitor/carer of a patient/resident of Grenoble University Hospital or volunteers at Grenoble University Hospital. * For control group only: MMSE score ≥ 26
Exclusion criteria
* For patient and control groups: People under guardianship or deprived of their freedom * For patient and control groups: Diagnosis of severe psychiatric disorders * For patient and control groups: Suspicion of pathologies related to alcohol dependence * For patient and control groups: No French social security coverage * For patient and control groups: Refusal to voluntarily participate in this study * For patient and control groups: People covered by articles L1121-5 to L1121-8 of the French Public Health Code * For patient group only: Suspicion of another neurodegenerative disease, such as fronto-temporal dementia, Parkinson's disease, Lewy body disease. * For patient group only: Clinical neuropsychological assessment did not reveal any cognitive impairment.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Memory performance in the Working memory task | 15 minutes | Percentage of correct immediate recall, computed with strict serial recall criterion (item identity + correct position) and computed with item recall criterion (item identity only). |
| Processing performance in the Working memory task | 15 minutes | Percentage of correct response in the spatial part of working memory task |
| Reaction time | 30 minutes | Reaction time for each distractor (in ms) in the spatial part of working memory task |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Trail Making Test - Part A (time) | 2 minutes | This test evaluate motor speed processing Time in seconds |
| Stroop Test - major interference part (errors) | 90 secondes | this part of stroop test measures strong inhibition process number of errors is noted, from 0 to 24 |
| Mini-Mental State Examination (MMSE) | 15 minutes | MMSE is a test evaluate global cognitive functioning Score from 0 to 30 A higher score mean a better cognitive efficiency |
| Digit span forward WAIS IV (digit number) | 5 minutes | The participant's span is noted, corresponding to the longest number of sequential digits that can be repeated forward. |
| Digit span forward WAIS IV (standard note) | 5 minutes | This scale permitted to obtain a standard note from 0 to 19 A higher score means a better performance |
| Digit span backward WAIS IV (digit number) | 5 minutes | The participant's span is noted, corresponding to the longest number of sequential digits that can be repeated backward. |
| Digit span backward WAIS IV (standard note) | 5 minutes | This scale permitted to obtain a standard note from 0 to 19 A higher score means a better performance |
| Stroop Test - denomination part | 30 secondes | the denomination part of stroop test measures processing speed time is taken, in seconds |
| Stroop Test - minor interference part (Time) | 30 secondes | this part of stroop test measures low inhibition process time is taken, in seconds |
| Stroop Test - minor interference part (errors) | 30 secondes | this part of stroop test measures low inhibition process number of errors is noted, from 0 to 24 |
| Stroop Test - major interference part (time) | 90 secondes | this part of stroop test measures strong inhibition process time is taken, in seconds |
| Trail Making Test - Part A (errors) | 2 minutes | This test evaluates motor speed processing Number of errors is noted |
| Trail Making Test - Part B (time) | 5 minutes | This test evaluates mental flexibility Time in seconds |
| Trail Making Test - Part B (errors) | 5 minutes | This test evaluates mental flexibility Number of errors is noted |
| Category fluences | 5 minutes | Number of correct words is noted |
| Memory evaluation (16-item Free and Cued Recall, or GERIA-12) | 40 minutes | These tests evaluate verbal episodic memory Scores are noted for each trail, from 0 to 16 (RL-RI/16) or 0 to 12 (Geria-12) A higher score means a better performance |
| Naming task | 40 minutes | This test evaluate the capacity to correctly name a picture Score is noted, from 0 to 40 A higher score means a better performance |
| Behavior rating inventory of executive function | 10 minutes | Questionnaire (french version) on patient's daily executive functioning, completed by a relative of the patient, if present Global score from 75 to 225, composing by several composite scores. A higher score means a more severe executive dysfonctionning in daily life |
| Instrumental Activities of Daily Living | 5 minutes | Questionnaire completed by a professional (nurse or doctor) with the patient and an accompagniant if present Score from 0 to 8 A higher score mean a better autonomy in daily life |
| Activities of Daily Living | 5 minutes | Questionnaire completed by a professional (nurse or doctor) with the patient and an accompagniant if present Score from 0 to 6 A higher score mean a better autonomy in daily life |
Contacts
Primary ContactAmelie Bichon
Outcome results
None listed