Short-term memory after all: comment on Sederberg, Howard, and Kahana (2008)

P. B. Sederberg, M. W. Howard, and M. J. Kahana have proposed an updated version of the temporal-context model (TCM-A). In doing so, they accepted the challenge of developing a single-store model to account for the dissociations between short- and long-term recency effects that were reviewed by E. J. Davelaar, Y. Goshen-Gottstein, A. Ashkenazi, H. J. Haarmann, and M. Usher (2005). In this commentary, the authors argue that the success of TCM-A in addressing the dissociations is dependent not only on an episodic encoding matrix but--critically--also on its implicit use of a short-term memory store--albeit exponential rather than buffer-like. The authors also highlight some difficulties of TCM-A in accounting for these dissociations, and they argue that TCM-A fails to account for critical data--the presentation-rate effect--that dissociates exponential and buffer-like models.     

The long-term recency effect in recognition memory

Three classes of theories explain the recency effect: the modal model, single-store models, and the composite view, which integrates the two positions. None could explain the absence of a long-term recency effect in recognition memory in previous studies. We suggest that prior work did not obtain a recency effect because testing used a multiple-probe rather than a single-probe recognition procedure. Here we tested memory using a single-probe recognition procedure. Experimental conditions included an immediate test, a delayed test after a filled interval, and a continuous-distractor paradigm in which the same filled delay preceded the first word and followed every study word. The long-term recency effect in continuous-distractor recognition was equivalent to the recency effect in immediate recognition. Its absence in the delayed recognition condition demonstrated that it was not attributed to the use of a putative short-term memory store. Single-store models and the composite view can account for this novel finding.     

Professional burnout and work stress among Israeli dental assistants

Professional burnout and work-related stress are known problems that have been the subject of in-depth examination among dentists. Nevertheless, these issues have not been widely studied among dental assistants. The aims of this study were threefold: to confirm the structure of a Work Stress Inventory (WSI) for Dental Assistants which was originally developed for Jordanian dental assistants (factor analysis); to evaluate work stress and burnout among Israeli dental assistants and to discover the factors predicting Israeli assistants’ burnout (regression analyses). The Maslach Burnout Inventory and the WSI were distributed by mail and in person. Varimax factor analysis revealed that the items which contribute to different aspects of work stress are similar among both Jordanian and Israeli populations. Among the 299 Israeli dental assistants who completed the questionnaires, the most stressful work-related factors were income, workload, and work hazards. Eighteen percent of the participants exhibited a high to very high level of burnout. Participants exhibited a moderate level of emotional exhaustion (EE), low level of depersonalization (DP), and high level of personal accomplishment (PA). Most WSI factors were found to correlate positively with EE and DP. Linear stepwise regression analyses revealed that the best predictor of EE was the dentist?assistant relationship, followed by workload, patient type, and salary. The best predictor of DP was patient suffering followed by dentist?assistant relationship, years of professional experience, and work hazards. Professional stress and burnout among dental assistants are important factors that can possibly affect the wellbeing of both dental personnel and their patients. Further studies are necessary to better understand these factors in addition to the effects of personal relationships on burnout among dentists and their assistants.     

Can massive but passive exposure to faces contribute to face recognition abilities?

Recent studies have suggested that individuation of other-race faces is more crucial for enhancing recognition performance than exposure that involves categorization of these faces to an identity-irrelevant criterion. These findings were primarily based on laboratory training protocols that dissociated exposure and individuation by using categorization tasks. However, the absence of enhanced recognition following categorization may not simulate key aspects of real-life massive exposure without individuation to other-race faces. Real-life exposure spans years of seeing a multitude of faces, under variant conditions, including expression, view, lighting and gaze, albeit with no subcategory individuation. However, in most real-life settings, massive exposure operates in concert with individuation. An exception to that are neonatology nurses, a unique population that is exposed to--but do not individuate--massive numbers of newborn faces. Our findings show that recognition of newborn faces by nurses does not differ from adults who are rarely exposed to newborn faces. A control study showed that the absence of enhanced recognition cannot be attributed to the relatively short exposure to each newborn face in the neonatology unit or to newborns' apparent homogeneous appearance. It is therefore the quality--not the quantity--of exposure that determines recognition abilities.     

Teaching by Examples: Implications for the Process of Category Acquisition

A new paradigm, the 'teaching-by-examples' paradigm, was used to shed new light on the process of category acquisition. In four experiments ( n = 90, 90, 115, 117), manipulating the variables of category structure, status of non-target category, learning mode, and teaching mode, participants first learned a category and then taught it to someone else. High agreement between participants on the teaching sequences was found across conditions, and a typical sequence was identified for each category structure. The typical participant-produced sequences startedwith several ideal positive cases, followed by anideal negative case and then borderline cases. The efficiency of such sequences for teaching was tested in another experiment ( n = 60), in which they were compared with sequences emphasizing category borders and sequences emphasizing each dimension separately. The typical participant-produced sequences induced the most efficient learning. It is proposed that the pattern of performance may provide a rich source of data for testing and fine-tuning models of category acquisition.     

Desiring at Will and Humeanism in Practical Reason

Hume's farmer's dilemma is usually construed as demonstrating the failure of Humeanism in practical reason and as providing an argument in favor of externalism or the theory of resolute choice. But thedilemma arises only when Humeanism is combined with the assumptionthat direct and intentional control of our desires – desiring atwill – is impossible. And such an assumption, albeit widely accepted,has little in its support. Once we reject that assumption we can describe a solution to the dilemma within the bounds of Humeanism. Moreover, wefind in this new solution as argument for the idea of desiring at will.     

The demise of short-term memory revisited: empirical and computational investigations of recency effects

In the single-store model of memory, the enhanced recall for the last items in a free-recall task (i.e., the recency effect) is understood to reflect a general property of memory rather than a separate short-term store. This interpretation is supported by the finding of a long-term recency effect under conditions that eliminate the contribution from the short-term store. In this article, evidence is reviewed showing that recency effects in the short and long terms have different properties, and it is suggested that 2 memory components are needed to account for the recency effects: an episodic contextual system with changing context and an activation-based short-term memory buffer that drives the encoding of item-context associations. A neurocomputational model based on these 2 components is shown to account for previously observed dissociations and to make novel predictions, which are confirmed in a set of experiments.     

Effects of familiarity on the perceptual integrality of the identity and expression of faces: the parallel-route hypothesis revisited

The effects of familiarity on selective attention for the identity and expression of faces were tested using Garner's speeded-classification task. In 2 experiments, participants classified expression (or identity) of familiar and unfamiliar faces while the irrelevant dimension of identity (or expression) was either held constant (baseline condition) or varied randomly (filtering condition). Selective attention was measured by the difference in performance between these 2 conditions. Failure of selective attention was larger for familiar than for unfamiliar faces. In addition, failure of selective attention was found both for identity and for expression judgments. These findings show that familiarity increases (he perceptual integrality between identity and expression, and they question previous studies arguing that identity judgments are always resistant to irrelevant variations in expression. The authors suggest that the systems processing identity and expression are interconnected in that facial identity serves as a reference from which expressions can be more easily derived.     

Impact of a television film on attitudes toward mental illness

The possible impact of a prime time television film portraying a mentally ill killer was investigated. Groups of college students were shown the film with and without a film trailer reminding viewers that violence is not characteristic of mentally ill persons. A third group viewed a film not about mental illness. Postfilm responses to the Community Attitudes toward the Mentally Ill scale indicated that those who saw the target film expressed significantly less favorable attitudes toward mental illness and community care of mentally ill persons than did those who saw the control film, regardless of whether of not they received the trailer along with the target film. Results support concerns that media depictions add to mental illness stigma and also suggest that corrective information alone may be sufficient to counteract the stigmatizing impact of such audience-involving mass media portrayals.     

Serial reaction time performance following right parietal lobe damage

The serial reaction time task (SRT) is used to assess implicit sequence learning. Neuroimaging studies implicate parietal involvement; however, the necessity of this area is unclear. We tested six unilateral right parietal patients and compared their performance to matched controls. Both groups showed similar levels of learning and explicit awareness. Two patients with the largest lesions extending into either frontal or cerebellar regions showed no learning. These data suggest that implicit sequence learning can occur despite damage to the right parietal lobe.