PRESERVED PATTERN COMPLETION PRIMING FOR NOVEL, ABSTRACT GEOMETRIC SHAPES IN AMNESICS OF SEVERAL ETIOLOGIES

Two experiments were conducted using a paradigm developed by GABRIELI et al., Neuropsychologia 28, 417-427, 1990, which assessed both indire ct and direct memory performance in a completion task for novel abstra ct geometric patterns. The preferred method of scoring was the lines m ethod, based on the number of correct and incorrect lines produced for each item. It was chosen because it is both the simplest and the most informative measure. Two methods of scoring were used in previous wor k, namely, the strict whole figure method and the lenient whole figure method (GABRIELLI et al., 1990: VERFAELIE et al., Brain Cognit. 18, 3 4-45. 1992). Therefore to facilitate comparisons between studies and t o determine the characteristics of different scoring methods, results with all three measures were included. In Experiment 1, two different encoding strategies of naming and copying were used in order to explor e the relationship between indirect and direct memory performance. Ind irect memory performance in the naming condition was at baseline where as in the copying condition it was significantly above baseline. Cued recall did not differ across encoding conditions but recognition was h igher in the naming condition than the copying condition. In Experimen t 2, an attempt was made to extend the findings of two studies, one wi th H.M. (GABRIELLI et al., 1990) and one with nine Korsakoffs (VERFAFL IE et al., 1992), to a larger group of 14 amnesics of several aetiolog ies. Indirect memory performance was found to be equivalent for the am nesics and their matched controls, only when the lenient and the lines methods of scoring were used. Recognition and cued recall performance was impaired for the amnesics compared to the controls.