failure to recruit 83/99

Memory for action is especially important in everyday life although current literature is not very abundant. The enactment effect (i.e. better memory for performed actions than for verbally encoded sentences) is usually described as a robust effect in aging and can be found in many diseases. Although the enactment effect has been studied for three decades, there is still no consensus on how it enhances memory. Therefore, in order to gain additional insight into the representational basis of the enactment effect, in the present study, the investigators propose to test neurological patients. The investigators suggested that memory for action should be better than memory for verbally encoded information in Alzheimer's disease and Parkinson's disease.

If patients with Alzheimer's disease (AD) and Parkinson's disease (PD) have no cognitive assessment during the last 6 months, then they will realize different tests: MMSE (1), HAD (2), a cognitive assessment (3); (4); BREF (5); Assessment of apraxia, (6). Controls will perform the same tests to verify that they have no cognitive impairment. Then, two experimental conditions will be presented in all patients and controls: a first in which participants will have to name drawings (verbal learning) and a second in which they will have to reproduce an action associated with drawings (action learning). Immediately after this learning phase, a recognition task will be available and therefore participants will have to recognize drawings that had been presented previously. The main criteria used in the statistical analysis will be the correct recognition score.

1. = Folstein et al., 1975,
2. = Zigmond & Snaith, 1983,
3. = Dubois et al., 2002;
4. = Godefroy et al., 2008;
5. = Dubois et Pillon, 2000;
6. = Mahieux-Laurent, 2009.

Inclusion Criteria for 3 arms:

• Patient affiliated to a social security system
• Age between 55 and 80 years
• Normal vision and hearing or successfully corrected
• French mother tongue
• Signature of consent by participants

Specific criteria for inclusion of MA patients:

• Probable AD diagnosis made by a neurologist (McKhann et al., 2011)
• Mini-Mental State Examination (MMSE): score > 22
• Stable treatment for two months minimum.

Specific criteria for inclusion of PD patients:

• PD diagnosed by a neurologist (Postuma et al., 2015)
• Stable treatment for two months minimum.
• Mini-Mental State Examination (MMSE): score > 27
• Under dopaminergic treatment

Exclusion Criteria for 3 arms:

• Other neurological or psychiatric history
• Anxiety and depressive symptoms (assessed by the scale of depression-anxiety HAD; Zigmond & Snaith, 1983)
• Inability to communicate
• Significant impairment of judgment
• Delusional or psychotic state

Criteria common for non-inclusion of AD and PD patients:

• Other neurological or psychiatric history
• Anxiety and depressive symptoms (assessed by the scale of depression-anxiety HAD; Zigmond & Snaith, 1983)
• Inability to communicate
• Significant impairment of judgment
• Delusional or psychotic state

Criteria for non-inclusion of PD patients:

- Motor fluctuations

Criteria for non-inclusion of controls:

• Psychiatric or neurological disorders
• Anxiety and depressive symptoms (assessed by the scale of depression-anxiety HAD; Zigmond & Snaith, 1983)