Impaired Learning in Patients With Closed-Head Injuries: An Analysis of Components of the Acquisition Process

Several studies have already shown a deficit in learning ability following closed-head injury (CHI). Moreover, different learning curves have been claimed to characterize different head-injured subgroups (Luria, 1973). The present study separated the learning process into two different components: the number of new words added in each learning trial, and the number of words omitted from trial to trial. The Rey Auditory Verbal Learning Test was administered to 30 normal subjects and 30 CHI patients. Analysis of the number of words recalled in each of the five learning trials showed that, relative to the CHI group, the control group recalled a greater number of words and exhibited a steeper learning curve. Further analysis revealed that the control group's steeper learning curve was a product of both a significantly greater increment of words in each trial and a significantly smaller number of words omitted from trial to trial. The clinical and theoretical implications of the distinction between addition and omission of information in the learning process are discussed.