Is Alaska an Aberration or the Worst Case? A Robust Regression Approach to Understanding Inter-State Variations of Forcible Rape

Alaska’s rape rate perennially exceeds that of all other states. This study considers Alaska’s socioeconomic extremes—its frontier demography, its externally dependent resource economy, and its military presence—as explanations for inter-state variations of sexual violence. Robust regression procedures that accommodate extreme values were used to account for the effects of measures capturing Alaska’s unique socioeconomic qualities on state-level rape rates. The results showing that other economically dependent states with frontier demographic structures also report elevated rape rates indicate that despite its endemic levels of sexual violence, Alaska is not an aberration but is instead the worst case possible.     

Task-switching performance with 1:1 and 2:1 cue-task mappings: not so different after all

When task-switching studies use the task-cuing procedure with a 1:1 cue-task mapping, task switching and cue switching are confounded, which is problematic for interpreting switch costs. The use of a 2:1 cue-task mapping is a potential solution to this problem, but it is possible that introducing more cues may also introduce marked changes in task-switching performance. In 5 experiments involving 160 subjects, the authors compared performance with 1:1 and 2:1 mappings across several methodological changes. Differences in switch costs between mappings were small and, in most analyses, nonsignificant. In all experiments, both mappings yielded significant reductions in switch cost across cue-target interval, and there were significant cue-switching effects with the 2:1 mapping. A model of cue encoding fit the data from both mappings about equally well. Overall, task-switching performance was more similar than it was different between mappings, leading the authors to suggest that the use of a 2:1 mapping is a viable solution to the problem associated with a 1:1 mapping.     

A memory-based model of Hick's law

We propose and evaluate a memory-based model of Hick’s law, the approximately linear increase in choice reaction time with the logarithm of set size (the number of stimulus–response alternatives). According to the model, Hick’s law reflects a combination of associative interference during retrieval from declarative memory and occasional savings for stimulus–response repetitions due to non-retrieval. Fits to existing data sets show that the model accounts for the basic set-size effect, changes in the set-size effect with practice, and stimulus–response-repetition effects that challenge the information-theoretic view of Hick’s law. We derive the model’s prediction of an interaction between set size, stimulus fan (the number of responses associated with a particular stimulus), and stimulus–response transition, which is subsequently tested and confirmed in two experiments. Collectively, the results support the core structure of the model and its explanation of Hick’s law in terms of basic memory effects.     

Separating cue encoding from target processing in the explicit task-cuing procedure: are there "true" task switch effects?

Six experiments were conducted to separate cue encoding from target processing in explicitly cued task switching to determine whether task switch effects could be separated from cue encoding effects and to determine the nature of the representations produced by cue encoding. Subjects were required to respond to the cue, indicating which cue was presented (Experiments 1, 3a, and 4a) or which task was cued (Experiments 2, 3b, and 4b), before performing the cued task on the target. Cue encoding was successfully separated from target processing when the cue response indicated which task was cued but not when it indicated which cue was presented. Task switch effects were found when this separation was successful, suggesting that there are "true" task switch effects independent of cue encoding. Analysis of the conditions required for successful separation suggested that cue encoding results in a semantic categorical representation of the task to be performed rather than verbal or phonological representations of individual cues. Implications for the authors' past modeling of task-switching performance are discussed.     

Task-set inhibition in chunked task sequences

Exploring the hierarchical control relationship between different levels of representation and processing is important for understanding how the mind controls itself. In the present study, the relationship between chunking (a sequence-level process) and task-set inhibition (a task-level process) in the performance of task sequences was investigated to evaluate the hypothesis that within-chunk facilitation reduces then−2 repetition cost (slower performance forn−2 task repetitions than forn−2 task switches) attributed to task-set inhibition. An experiment is reported in which subjects were induced to chunk sequences such thatn−2 repetitions occurred within or between chunks. Direct evidence of chunking was obtained, andn−2 repetition cost was smaller whenn−2 repetitions occurred within chunks than between chunks. These findings are consistent with an elaborated hypothesis that attributes the reduction inn−2 repetition cost to priming of task goals rather than direct modulation of task-set inhibition.     

Defining task-set reconfiguration: The case of reference point switching

Some researchers argue that task switching involves task-set reconfiguration-that is, changing the existing task set to perform a different task. Although this idea is intriguing, it is often unclear what is reconfigured and which processes are involved in reconfiguration. We addressed these issues by defining task sets, identifying differences between them, and obtaining evidence that was diagnostic of reconfiguration. In two experiments, subjects performed relative judgment tasks that involved comparing a target with a reference point that repeated or switched across trials. The task was the same on every trial, but the task set was not, because a task-set parameter-the reference point-had to be changed. Target-reference point distance effects that changed with the reference point provided diagnostic evidence that reconfiguration occurred, and this reconfiguration led to switch costs. We discuss how our approach can be generalized to define reconfiguration more clearly in other task-switching situations. nt|mis|This research was supported by Grants BCS 0133202 and BCS 0446806 from the National Science Foundation to G.D.L.     

Systemic change in limited family therapy

Some families present with so many problems and disordered family processes that where and how to begin is an extremely important question. When premature termination of therapy also appears likely, a family therapist may simply attempt to initiate a structural change within the family system so that the family can continue on its own. This article describes the responses of a highly chaotic family to such a single therapeutic intent.     

Fragment memories mark the end of childhood amnesia

Adults described and dated two kinds of first remembrances: a personal event memory (the recollection of a personal episode that had occurred at some time in some place) and a memory fragment (an isolated memory moment having no event context and remembered, perhaps, as an image, a behavior, or an emotion). First fragment memories were judged to have originated substantially earlier in life than first event memories--approximately 3 1/3 years of age for first fragment memories versus roughly 4 years of age for first event memories. We conclude that the end of childhood amnesia is marked not by our earliest episodic memories, but by the earliest remembered fragments of childhood experiences.     

Encoding context and false recognition memories

False recognition of an extralist word that is thematically related to all words of a study list may reflect internal activation of the theme word during encoding followed by impaired source monitoring at retrieval, that is, difficulty in determining whether the word had actually been experienced or merely thought of. To assist source monitoring, distinctive visual or verbal contexts were added to study words at input. Both types of context produced similar effects: False alarms to theme-word (critical) lures were reduced; remember judgements of critical lures called old were lower; and if contextual information had been added to lists, subjects indicated as much for list items and associated critical foils identified as old. The visual and verbal contexts used in the present studies were held to disrupt semantic categorisation of list words at input and to facilitate source monitoring at output.