Conceptual Relativism

What is conceptual relativism? Several formulations of the idea that truth, or existence, is somehow relative to conceptual schemes are considered. All are found lacking.     

Aging, spaced retrieval, and inflexible memory performance

Spaced retrieval is a memory-training technique whereby information is tested at progressively longer delays. Two experiments were conducted in order to examine the effects of spaced retrieval on controlled recollection and automatic influences of memory. In Experiment 1, word pairs were read once, three times, or once and retrieved twice by young and older adults. Retrieval practice improved performance on a later test for both age groups. Experiment 2 was arranged so that recollection opposed automatic influences of retrieval practice. Retrieval practice increased intrusions on a later test only for older adults. Results suggest that because of a deficit in recollection, older adults were less able to oppose the automatic influence of spaced retrieval and thus exhibited less flexible memory performance.     

Individual differences in the perception of similarity and difference

Thematically related concepts like coffee and milk are judged to be more similar than thematically unrelated concepts like coffee and lemonade. We investigated whether thematic relations exert a small effect that occurs consistently across participants (i.e., a generalized model), or a large effect that occurs inconsistently across participants (i.e., an individualized model). We also examined whether difference judgments mirrored similarity or whether these judgments were, in fact, non-inverse. Five studies demonstrated the necessity of an individualized model for both perceived similarity and difference, and additionally provided evidence that thematic relations affect similarity more than difference. Results suggest that models of similarity and difference must be attuned to large and consistent individual variability in the weighting of thematic relations.     

Matching-to-sample abstract-concept learning by pigeons

Abstract concepts--rules that transcend training stimuli--have been argued to be unique to some species. Pigeons, a focus of much concept-learning research, were tested for learning a matching-to-sample abstract concept. Five pigeons were trained with three cartoon stimuli. Pigeons pecked a sample 10 times and then chose which of two simultaneously presented comparison stimuli matched the sample. After acquisition, abstract-concept learning was tested by presenting novel cartoons on 12 out of 96 trials for 4 consecutive sessions. A cycle of doubling the training set followed by retraining and novel-testing was repeated eight times, increasing the set size from 3 to 768 items. Transfer performance improved from chance (i.e., no abstract-concept learning) to a level equivalent to baseline performance (>80%) and was similar to an equivalent function for same/different abstract-concept learning. Analyses assessed the possibility that item-specific choice strategies accounted for acquisition and transfer performance. These analyses converged to rule out item-specific strategies at all but the smallest set-sizes (3-24 items). Ruling out these possibilities adds to the evidence that pigeons learned the relational abstract concept of matching-to-sample.     

In search of clarity: self-esteem and domains of confidence and confusion

To date, research suggests that self-concept clarity is a monolithic construct: Some people have clearly defined self-concepts in all domains, whereas others do not. The authors argued that self-concept clarity is instead multifaceted and varies across trait domains. The authors predicted that social commodities (SCs; e.g., looks, popularity, social skills) would show less self-concept clarity than would communal qualities (CQs; e.g., kindness, warmth, honesty), due to domain differences in observability, ambiguity, and controllability. Results replicated past findings that self-esteem predicts self-concept clarity but also demonstrated that participants' SC self-views were less clear than their CQ self-views. Moreover, people showed greater clarity about traits that were lower in observability and higher in ambiguity and controllability. These findings suggest that everyone, regardless of self-esteem, has self-concept domains of relative confidence and confusion.     

Neural correlates of transformational apparent motion

Transformational apparent motion (TAM) arises when a shape that is abruptly flashed on and off next to a static shape of similar color or texture appears as a protrusion that extends and retracts smoothly from the static object. Here we report that the strength of the TAM percept can be predicted from the waveform of visual evoked potentials (VEPs) measured while observers rated their percepts. The VEPs at pattern onset and offset are maximally symmetric when the static inducer and the flashing patches of the display are of the same contrast. VEP symmetry is affected by how the two patches can be matched as a single surface and may reflect the relative contribution of different motion and object detection systems in visual cortex.     

Correlates of suicidality among patients with psychotic depression

The independent association of age and other factors with suicidality in patients with major depression with psychotic features was examined. Of the 183 study participants, 21% had a suicide attempt during the current episode. Male gender, Hispanic background, past suicide attempt, higher depression scores, and higher cognitive scores were each independently associated with greater intensity of current suicidality. Older age was independently associated with a lower risk of a lifetime suicide attempt. These findings reinforce the evidence that patients with psychotic depression are at high risk for suicide and underscore the importance of examining correlates of suicidality specific to patients with psychotic depression.