Contextual change and skill acquisition in visual search. Does the rate of change affect performance?

The present investigation examined the effects of training context on the development of a skill in a semantic category visual search task. Thirty-two subjects were trained in a visual search task which allowed the separate examination of feature learning and attention strengthening. Subjects were trained in a Consistently Mapped (CM) condition which allowed both feature learning and attention strengthening, 'Attenuated Strength' search conditions which allowed only feature learning, and a Variably Mapped (VM) condition which allowed neither feature learning or attention strengthening. The present experiment also examined the temporal characteristics of feature learning by manipulating the training context which was defined as the number of trials in a row that a particular search condition appeared. There were four different training contexts used (1, 5, 10, and 50) and eight subjects were assigned to each. Each subject performed 11,000 training trials. Analysis of the reaction time (RT) data indicated that within each training context, RT was fastest for the CM condition, intermediate for the Attenuated Strength conditions, and slowest for the VM condition. The results also suggest that 10 trials were sufficient for feature learning to occur. Furthermore, while there was evidence of attention strengthening in the CM condition there was no evidence of attention strengthening in the Attenuated Strength conditions. For inconsistent tasks that allow feature learning, the rate at which the context changes is a critical variable in determining final task performance.