<qa>  What is the maximum performance level?4. Subjects will have baseline MCCB battery scores which meet the following criteria. Subjects will meet the following cognitive performance criteria: a. Maximum performance level: Performance at least 1.0 standard deviation SD from perfect on the following three measures: Letter-number span 24, Hopkins Verbal Learning Test HVLT total 31, Continuous Performance Test CPT d-prime 3.47 and b. 