The medium or the message? Communication relevance and richness in trust games

Subjects communicated prior to playing trust games; the richness of the communication media and the topics of conversation were manipulated. Communication richness failed to produce significant differences in first-mover investments. However, the topics of conversation made a significant difference: the amounts sent were considerably higher in the unrestricted communication conditions than in the restricted communication and no-communication conditions. Most importantly, we find that first-movers’ expectations of second-movers’ reciprocation are influenced by communication and strongly predict their levels of investment.     

Effects of instruction on learners’ ability to generate an effective pathway in the method of loci

One of the most effective mnemonic techniques is the well-known method of loci. Learning and retention, especially of sequentially ordered information, is facilitated by this technique which involves mentally combining salient loci on a well-known path with the material to be learned. There are several variants of this technique that differ in the kind of path that is suggested to the user and it is implicitly assumed that these variants are comparable in effectiveness. The experiments reported in this study were designed to test this assumption. The data of two experiments show that participants who are instructed to generate and apply loci on a route to their work recall significantly more items in a memory test than participants who are instructed to generate and apply loci on a route in their house. These results have practical implications for the instruction and application of the method of loci.     

Level of processing and the process-dissociation procedure: Elusiveness of null effects on estimates of automatic retrieval

We describe two experiments that used the process-dissociation procedure to investigate the effects of level of processing on estimates of controlled and automatic retrieval processes in word-stem completion tasks. Despite our best endeavours, we found the null effect of level of processing on estimates of automatic retrieval reported by Toth, Reingold, and Jacoby (1994) elusive. Estimates of automatic retrieval were not independent of level of processing but inversely related to it. In part, the reason was that, following deeper levels of processing, instructions to exclude recollected words led to floor effects. But the inverse relationship persisted even when floor effects were avoided. Only participants who were not given strict instructions in the exclusion task–and who also qualified as lax responders based on answers in a structured post-test interview–showed no effect of level of processing on estimates of automatic retrieval. This null effect apparently occurred because these participants failed to exclude words that they in fact recollected from the study list. This finding violates the critical assumption that in this task participants exclude recollected words. The results are therefore paradoxical. Successful replication of the null effect occurred only under conditions that preclude the very use of the procedure. This paradox has important implications for views on how consciousness should be conceived in relation to memory.     

Recollection deficits in dysphoric mood: An effect of schematic models and executive mode?

Depression and dysphoric mood states are often accompanied by quantitative or qualitative shifts in performance across a range of retention tasks. This study focuses on the recollection of both autobiographical events and word lists in dysphoric states. Recollection occurs when people are aware of some contextual detail allied to the encoding experience. This study establishes the presence of a recollection deficit in dysphoria in two distinct paradigms. In both autobiographical recall and in recognition memory, recollection in a dysphoric group was at lower levels than recollection in matched controls. The study examines the hypothesis that the extent of recollection is influenced by two factors: (1) the degree of differentiation of schematic mental models; and (2) the executive mode that predominates when memory tasks are carried out, with the latter assumed to be altered by rumination. The relationship between responses based on recollection and alternative mnemonic responses could be predicted by measures of these two factors. The results are discussed in terms of the Interacting Cognitive Subsystems model (Teasdale & Barnard, 1993) and the perspective it offers on the relationship between meaning systems and executive functions (Barnard, 1999).     

Functional focal retrograde amnesia: Lost access to abstract autobiographical knowledge?

We describe three patients exhibiting an acute reversible amnesia characterised by an impaired recollection of past events with preserved anterograde memory, thus consistent with a focal retrograde amnesia (FRA). This occurred after variable events: state of fugue, road accident, post-traumatic headache. Retrograde amnesia affected autobiographical memory so severely as to cover all of the patients' lives and to erase knowledge of their own identity. The retrieval of public events was variably affected, ranging from normality to severe impairment. No lesions were found on neuroimaging, and neurophysiological findings were unimpressive. FRA subsided in a few days, leaving a gap for the onset. The hypothesis of a psychogenic amnesia is considered, but overcoming the organic/psychogenic dichotomy the episodes appear as examples of “functional” memory inhibition, potentially triggered by different conditions, including events classifiable as psychic trauma. The clinical and neuropsychological traits of functional FRA are discussed. According to a current theory of autobiographical memory, the memory profile may be explained by a lost access to abstract autobiographical knowledge. Given some analogies with the more common transient global amnesia, a mechanism of spreading depression may also be hypothesised for functional FRA.     

Adapting to test structure: Letting testing teach what to learn

We propose that we encode and store information as a function of the particular ways we have used similar information in the past. More specifically, we contend that the experience of retrieval can serve as a powerful cue to the most effective ways to encode similar information in comparable future learning episodes. To explore these ideas, we did two studies in which all participants went through study–test cycles of single category lists while we manipulated the nature of the recognition tests. The recognition tests either included only same-category lures or only different-category lures. The experience of repeated testing leads participants to avoid conceptual-based strategies but only when conceptual knowledge was poorly diagnostic for recognition (i.e., in the same-category lures condition). In a second study with a similar manipulation, we showed that repeated testing with lures from the same category as study items improved performance in a final recall surprise test compared to conditions in which different-category lures were used. Such a difference is akin to the one obtained when encoding instructions focus on distinctive item features compared to cases in which the focus is on relational processing. We suggest that testing requirements lead to adaptive changes at encoding.     

Dynamic (Kinesthetic) Touch Perception in Preschool Children

The preschool years are an important time during which children gain proficiency using the hands for both performatory and perceptual functions that involve dynamic (kinesthetic) touch. We evaluated dynamic touch perception of object extent and found that preschool children are able to discriminate length by dynamic touch early, but perception is not very fine-tuned and perceptual attunement to inertial characteristics increased with age. An analysis comparing the performatory and perceptual functions of the hands showed links between performance and perception in dynamic touch tasks that did not require haptic–visual correspondence. We concluded that whereas dynamic touch is functional early in the preschool years, perceptual acuity is not very precise and haptic–visual correspondence remains immature. In addition, reliance on inertial properties as information to make judgments of length emerges between 3 and 5 years and attunement to inertial properties likely continues to develop throughout childhood because perceptual judgments of 5-year-olds did not reach adult levels. Tight links between the performatory and the perceptual functions of the hand suggest this is an important avenue for future research.