The subtraction of number of errors in learning from generalization (generalization – learning) in MCI subgroups and healthy control individuals.

<p>In almost all subjects, this measure is negative since subjects tend to make more errors in the learning than in the generalization phase. Interestingly, the generalization-learning performance in the MCD group were less negative than in vMCD or healthy controls (p < 0.03). Less negative values in the generalization-learning measure stem from comparable performance in learning and generalization. In the MCD group, less negative generalization-learning measure is due to a high number of errors in the generalization phase.</p

Homocysteine levels in MCI subgroups and healthy controls.

<p>Unlike what we expected, there was no effect of MCI severity (that is, between vMCD and MCD) on total homocysteine levels. As before, homocysteine levels in both MCI subgroups are higher than in healthy controls (HC).</p

Learning and generalization performance in MCI and healthy control individuals.

<p>We have found no difference between MCI and HC either in the number of errors the learning (A) or generalization phase (B).</p

Homocysteine levels inversely correlate with MMSE scores.

<p>Homocysteine levels inversely correlate with MMSE scores.</p

Total homocysteine levels are higher in individuals with MCI than in controls. HC = healthy controls.

<p>Total homocysteine levels are higher in individuals with MCI than in controls. HC = healthy controls.</p

Demographic information of healthy controls and individuals with MCI in the learning-and-generalization study.

<p>Abbreviation: n is number of subjects we tested; n filt is number of subjects after filtering out subjects who did not learn the task; CDR is clinical dementia rating; GDS is global deterioration scale; MMSE is mini mental status examination.</p

Reaction time in the learning and generalization task in MCI and healthy control individuals.

<p>We have found no difference between MCI and HC in RT in the learning (A) or generalization (B) phase.</p

Learning and generalization performance in MCI subgroups and healthy control individuals.

<p>(A) The healthy control (HC), vMCD, and MCD groups made similar number of errors during learning; (B) however, on generalization, the MCD group made more generalization errors than controls and individuals with vMCD.</p

Mean total of errors in the learning and generalization task in MCI and healthy control individuals.

<p>We found an effect of block in both groups in the learning but not generalization phase. As in prior analysis, by adding block number as a variable in ANOVA analysis, we found no difference between MCI and HC either in the number of errors the learning (A) or generalization phase (B).</p

Screen events on a sample trial of phase 1.

<p>(A) At start of trial, two objects appear, differing in color or shape but not both. (B) The participant chooses one object and that object is raised; if the choice was correct, a smiley face is revealed underneath. C) If incorrect, there is no smiley face.</p