Precise instructions determine participants’ memory search strategy in judgments of relative order in short lists

Memory often requires knowledge of the order of events. Previous findings about immediate judgments of relative order in short, subspan lists are variable regarding whether participants’ strategy is to search memory in the forward direction, starting from the first list item and progressing toward the end item, or in the backward direction, starting from the end item and progressing toward the start. We asked whether wording of the instructions influences participants’ search direction. Participants studied sequences of three to six consonants, and for an immediate, two-item probe of each list, judged which probe was presented earlier (“earlier” instruction) or later (“later” instruction) on the list. Forward and backward searches were supported for “earlier” and “later” instructions, respectively. Our findings suggest that participants have more than one effective strategy for order judgments in short lists, and that subtle instructional differences can bias memory search in either the forward or backward direction.     

Working Memory and On-Line Sentence Comprehension in Patients with Alzheimer's Disease

We examined the ability of patients with dementia of the Alzheimer's type (DAT) and normal controls to perform a sentence acceptability judgment task that required determining the referent for a reflexive pronoun. Performance on three different sentence types that differed in terms of syntactic complexity was assessed. Subjects performed the task alone and under two different dual-task conditions which required continuous, externally paced responses. DAT patients were more affected than controls by the dual-task conditions, but were not disproportionately impaired on the more complex sentence types. The failure of DAT patients to he disproportionately affected on the most complex sentence types in the dual-task conditions provides evidence for the separation of the processing resources that are used in sentence comprehension from those involved in other tasks.     

Comprehension of gerundive constructions by Broca's aphasics

Eleven diagnosed Broca's aphasics were tested for comprehension of sentences containing gerundive constructions. Results showed that, as a group, these patients were sensitive to grammatical distinctions signaled by “function” words, contrary to the predictions of some current theories about the specific deficits exhibited in this syndrome. Further analysis showed that the patients fell into two subgroups, one which exhibited sensitivity to the distinctions in normal grammar, and another which exhibited no sensitivity to such distinctions. This suggests that the syndrome may have different manifestations in different populations—patient age is suggested as a possible means for distinguishing the two groups. Suggestions for further research into the nature of the comprehension deficits exhibited by Broca's aphasics are made.     

From field experiments to program implementation: Assessing the potential outcomes of an experimental intervention program for unemployed persons

Demonstrated a procedure suggested by Bloom (1984) to provide estimates for the effects of an intervention on its actual participants compared to global effects on study participants in the intervention group, whether or not they showed up. Analyses were based on data collected in a field experiment that tested a preventive intervention for unemployed persons (Caplan, Vinokur, Price & van Ryn, 1989). Effect size estimates were two to three times larger for the actual participant group than for the entire experimental group on employment outcomes (e.g., earnings) and mental health (anxiety and depression). Further analyses produced results showing that compared to participants, the nonparticipants achieved significantly higher levels of reemployment at posttests and did not differ significantly from participants on all other outcomes. The results suggest that persons who most needed the intervention and benefited from it were drawn into it through self-selection processes.