Mild Cognitive Impairment

Introduction
Memory is the ability to maintain and use of information for the appropriate goal (1). Appropriate performance of memory depends on the health of many brain regions, including areas that are very sensitive to injury or disease. Learning and memory impairments are common complaints of individuals with symptoms of neurological disorders that impact on the daily activities and functional capabilities(2–4). Memory impairment is the most important reasons for seeking psychological evaluation in outpatient(2). In addition, many psychiatric and neurological diseases cause impairments in the process of memory(4–6). Mild cognitive impairment (MCI) is a clinical state between normal aging and dementia, and in many cases occur before dementia

Participants with MCI were referred to the clinic by neurologists. 30 cognitively normal controls with no evidence of cognitive impairment (CN) were recruited from the relatives of the patients. The identification of MCI was performed by an experienced neurologist and was based on the following: (1) existence of any subjective memory complaints; (2) normal orientation and general cognitive performance as described by a Folstein’s Mini-Mental State Examination (MMSE) score of 24 (Persian version); (3) normal score on language ability, evaluated by the Boston Naming Test—BNT; (4) the lack of a known cause of memory deficit, such as use of a medication known to affect memory performance or a major medical or neurological illness. Cognitively normal controls (CN) were essentially determined as individuals with the following criteria: (1) no established subjective memory complaints; (2) no proved recognizable cognitive and memory impairment; (3) MMSE score ≥27; (4) normal social functioning in the community; (5) no active neurologic or psychiatric diseases. Subjects’ data are presented in Table 1. The two groups were matched for age and sex and there were no significant differences between controls and MCI patients in educational level, the score of Edinburgh Handedness Inventory‏ and score of

The RAVLT contained 15 words read loudly by the examiner (with a 1-s interval between each word) for five sequential Trials (Trials 1 to 5), each Trial followed by a free-recall test. Participants were directed that they would hear a list of 15 words and that they should listen attentively since they would be requested to retrieve as many of the words as feasible. The sequence of presentation of words remained constant across Trials. After the fifth Trial, a list (list B) of interferer words (15 words), read to the subject by the examiner like previous Trials and followed by its free-recall test. After that, the examiner asks the participant to recall the words that belonged to list A, without reading it again (Trial 6). After a 20-minute interval, the examiner asks the participant to retrieve the words that belong to list A (Trial 7) without reading this list again. After Trial 7, the participant is presented with a test of memory recognition, in which a list containing the 15 words from list A, the 15 words from list B, in addition 20 distracting words (phonologically or semantically similar to the words in list A and B) read to the participant by the examiner. Upon each word read loudly, the participant is requested to mark if it belongs to list A, or not. The total time for use of the RAVLT ranges from 35 to 40 minutes. The following indices were