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To study the relative merits of three training principles - difficulty of training, specificity of training, and variability of training - subjects were trained to follow navigation instructions to move in a grid on a computer screen. Subjects repeated and then followed the instructions by mouse clicking on the grid. They were trained, given a short distractor task, and then tested. There were three groups, each receiving different message lengths during training: easy (short lengths), hard (long lengths), and mixed (all lengths), with all subjects given all lengths at test. At test, the mixed group was best on most lengths, the easy group was better than the hard group on short lengths, and the hard group was better than the easy group on long lengths. The results support the advantages of both specificity and variability of training but do not support the hypothesis that difficult training of the form used here would lead to overall best performance at test.

In three experiments, we examined transfer and contextual memory in a category search task. Each experiment included two phases (training and test), during which participants searched through category and exemplar menus for targets. In Experiment 1, the targets were from one of two domains during training (grocery store or department store); the domain was either the same or changed at test. Also, the categories were organized in one of two ways (alphabetically or semantically); the organization either remained the same or changed at test. In Experiments 2 and 3, domain and organization were held constant; however, categories or exemplars were the same, partially replaced, or entirely replaced across phases in order to simulate the dynamic nature of category search in everyday situations. Transfer occurred at test when the category organization or domain was maintained and when the categories or exemplars matched (partially or entirely) those at training. These results demonstrate that transfer is facilitated by overlap in training and testing contexts.

When some perceptual-motor relationships are reversed, participants might adopt a global inhibition strategy that replaces all normal movements with reversed movements. In two experiments, participants practiced moving a cursor from a start position to target locations. In a perceptual-motor reversal condition, in which horizontal but not vertical movements were reversed, participants were trained to move only to certain locations. Testing involved moving to all locations under the same reversal condition. Training on a subset of locations yielded partial transfer to untrained locations. These results support a global inhibition hypothesis modified to include both midcourse corrective movements and training specificity.

The response execution stage of cognitive skill consists of several substages, including finding the proper response location among available alternatives and moving the effector to the target location. In order to unravel the brain dynamics associated with the finding process, the present experiments used two experimental conditions. In the number condition, which requires both finding and moving, subjects are presented on each trial with a digit, 0-9, are required to find that digit on a circular clock face, and then to move a cursor to that target's location. In the arrow condition, an arrow pointing to the location of the target on the clock face circumference appears simultaneously with the target digit; no target finding is required because subjects need only to move the cursor along the path marked by the arrow. A pilot and the main experiment revealed that response initiation times but not movement times were affected by these experimental manipulations. Analysis of magnetoencephalographic (MEG) activity revealed an early occipital activity which was not affected by experimental manipulations. Later activity with central-parietal and parieto-temporal loci presumably reflected changes in the dorsal and ventral pathways, respectively, and these were affected by experimental conditions. Finally, finding processes seem to be associated with a second late activation of the ventral pathway presumably reflecting ongoing recognition processes.

We conducted two experiments to study the training of speeded responses to stimuli in a clock face array. Participants were trained on one clock face and later tested on either the same or a different clock face. The clock faces varied along 3 dimensions of change (left-right flip, up-down flip, and 180 degrees rotation). Skill acquisition was reflected in decreases in overall, initiation, and movement response times in the training and test phases except that movement time reached an asymptote during training and did not decrease further during test. Test performance was best when training and test used the same clock face and worst when the training to test change involved an up-down flip. The transition to different clock faces was consistent with an interpretation based on the violation of expectations about target positions acquired during training. Consistent trial-by-trial feedback led to better initiation time but not movement time during training than periodic feedback, but this effect did not persist into the test phase.

In 2 experiments, participants used a keyboard to enter 4-digit numbers presented on a computer monitor under conditions promoting fatigue. In Experiment 1, accuracy of data entry declined but response times improved over time, reflecting an increasing speed-accuracy trade-off. In Experiment 2, the (largely cognitive) time to enter the initial digit decreased in the 1st half but increased in the 2nd half of the session. Accuracy and time to enter the remaining digits decreased across though not within session halves. The (largely motoric) time to press a concluding keystroke decreased over the session. Thus, through a combination of facilitation and inhibition, prolonged work affects the component cognitive and motoric processes of data entry differentially and at different points in practice., ((c) 2004 APA, all rights reserved.)

Two experiments examined the relationship between implicit and explicit measures of memory for information encoded in a motoric task, called data entry. In both experiments, subjects entered lists of digit sequences with a computer keypad. They were retested on the same task after a delay of up to 1 month. At retention, implicit memory for the digit lists was evidenced by faster entry of old relative to new lists in both experiments. In Experiment 1, subjects were able to discriminate old from new lists. Recognition memory of old lists was better after than before entering the lists. In Experiment 2, perceptual and motoric contributions to the old/new difference in typing speed were isolated by means of a transfer paradigm. The results showed that the entry-speed advantage for the old lists was due to the separate reinstatement at the retention test of both perceptual and motoric procedures encoded earlier. Implicit and explicit measures of memory were found to be dependent rather than independent. The findings from this study are interpreted within a framework of memory based on procedural reinstatement.