45 adults who had suffered traumatic brain injuries were examined, using a group form of dynamic assessment. The purposes were (a) to determine the applicability of group dynamic assessment in this population, and (b) to determine whether even short-term and transient gains in performance would be possible in persons who are years past the acute phase of their brain injuries. Three principal instruments were used: Rey’s Complex Figure (CF), Haywood’s Test of Verbal Abstracting (TVA), and the Representational Stencil Design Test (RSDT) from the Learning Potential Assessment Device of Feuerstein et al., plus a series of verbal memory tests that we attached to the TVA. 21 of the participants were given group mediation of basic cognitive and metacognitive operations, between pre-testing and post-testing, whereas the 24 participants in the control condition were given no mediation beyond that necessary to understand what was required in the tasks. Instead, they worked on alternative tasks. In all cases the sequence was Introduction and Instructions, Pretest (no mediation), Period of Training (mediation of essential cognitive and metacognitive strategies) or alternative activities, Posttest (no mediation). In addition to the interposed cognitive mediation, administration of the TVA included 2- and 5-exemplar versions of two forms, A and B, of the test, thus yielding four verbal abstracting scores: A-2 (Form A with 2 exemplars; “In what way are yellow and brown alike?”), A-5 (“In what way are yellow, brown, green, purple, and orange alike?”), B-2, and B-5. As expected, initial performance was quite low on all of these. The data revealed improved performance following intervention on all of these tasks for the participants in the mediated condition. On the average, participants in the control samples started out at a higher level of performance than did those in the mediated condition, making clear interpretation somewhat difficult.
On the TVA, the greatest improvement in verbal abstracting performance was observed between A-2 and A-5; that is, the addition of 3 more exemplars of each concept appeared to make a great difference in both groups. There was also significant differential improvement between A-2 and B-2, showing a positive effect of metacognitive mediation on verbal abstracting. There was no mediation for verbal memory, so little change was expected on the memory tests; however, data from the word memory tests suggested that mediation of metacognitive strategies can improve verbal memory performance, possibly by encouraging the use of categorizing strategies. On the CF, group mediation of organization, planning, and attention led to modest improvement in the copying score but a dramatic improvement in producing the figure from memory; i.e., production of the figure from memory after the period of mediation showed a great improvement both in number of elements recalled and placed in the drawing and in organization and sequence. On the RSDT, undoubtedly the most cognitively complex of these tasks, initial performance was poor, as expected, but there was substantial improvement following a period of mediational training.
