The role of attention in subitizing: Is the magical number 1?

Subitizing, the fast and accurate enumeration of up to about 3 or 4 objects, has often been thought to be dependent on limited-capacity preattentive mechanisms. We used an attentional blink paradigm to investigate the extent to which subitizing requires attentional resources. On each trial, subjects identified a target letter in an RSVP stream and then enumerated dots presented in the stream that were either simultaneous with the target letter or followed it by up to 400 ms. For numerosities from 2 to 9, evidence of an attentional blink was observed; only enumeration of 0 or 1 elements was independent of lag. Thus, even enumeration of 2–3 objects, which is within the traditional subitizing range, appears to require attentional resources. The relation of this work to studies on the attentional requirements of detecting a unique item among distractors, a supposedly preattentive discrimination, is briefly discussed.     

Early locus of a linguistic variable in a fast priming task

The syllable and the morpheme are known to be important linguistic variables, but is such information involved in the early stages of word recognition? Syllable‐morpheme information was manipulated in the early stage of word naming by means of the fast priming paradigm. The letters in the prime were printed in a mixture of lower‐ and upper‐case letters. The change from lower to upper case occurred either at a syllable‐morpheme boundary, before the boundary, or after it (e.g., reTAKE, rETAKE, or retAKE) creating either an intact pair or a broken one. The target was always in lower case (e.g., retake). The results of Experiments 1 and 2 revealed that intact syllable and morpheme information facilitated word naming at a short Stimulus Onset Asynchrony (below awareness) but not at a long SOA, suggesting that the use of such information is automatic. A second set of experiments attempted to determine if syllable information alone could facilitate word processing. In Experiments 3 and 4, monomorphemic words were divided either at, before, or after the syllable boundary (e.g., rePEL, rEPEL, or repEL). The primes were all pseudomorphemic in the sense that the initial syllables could appear as a morpheme in other words (e.g., restate) but were not morphemic in the target words (e.g., repel). The second syllable was neither morphemic nor pseudomorphemic. Using the same SOAs as in Experiments 1 and 2, intact syllables were found to be facilitative at the short SOA, but not at the long SOA. Thus, the syllable plays a role in an early stage of word recognition. Whether morphemes that are not syllables are facilitative is still to be determined in this paradigm.     

Lifestyle interventions in the treatment of childhood overweight: a meta-analytic review of randomized controlled trials.

CONTEXT: Evaluating the efficacy of pediatric weight loss treatments is critical. OBJECTIVE: This is the first meta-analysis of the efficacy of RCTs comparing pediatric lifestyle interventions to no-treatment or information/education-only controls. DATA SOURCES: Medline, PsycINFO, and Cochrane Controlled Trials Register. STUDY SELECTION: Fourteen RCTs targetting change in weight status were eligible, yielding 19 effect sizes. DATA EXTRACTION: Standardized coding was used to extract information on design, participant characteristics, interventions, and results. DATA SYNTHESIS: For trials with no-treatment controls, the mean effect size was 0.75 (k = 9, 95% confidence interval [CI] = 0.52-0.98) at end of treatment and 0.60 (k = 4, CI = 0.27-0.94) at follow-up. For trials with information/education-only controls, the mean ES was 0.48 (k = 4, CI = 0.13-0.82) at end of treatment and 0.91 (k = 2, CI = 0.32-1.50) at follow-up. No moderator effects were identified. CONCLUSIONS: Lifestyle interventions for pediatric overweight are efficacious in the short term with some evidence for extended persistence. Future research is required to identify moderators and mediators and to determine the optimal length and intensity of treatment required to produce enduring changes in weight status.     

Post-experimentalist pragmatism

Rorty's neopragmatism is an attempt to retrofit Dewey's experimentalism for the post-modern situation. Specifically, he substitutes "language" for "experience" and "culture" for "science", to arrive at a philosophy "no closer to science than to art". I argue that the first move results from misunderstanding of the role experience plays in the context of verification in Dewey's experimental logic. The second move leaves Rorty without any alternative method even for approaching the very problems which Dewey proposed to solve with his experimentalism.     

Long Term Outcomes to Family Caregiver Empowerment

The Vanderbilt Caregiver Empowerment Project evaluated a training program designed to enhance empowerment of caregiver and their subsequent involvement in the mental health treatment of their children. The intervention utilized a multi-component parent training curriculum that was designed to enhance: (a) knowledge of the service system; (b) skills needed to interact with the mental health system; and (c) the caregiver' s mental health services self-efficacy designed to improve caregivers beliefs in their ability to collaborate with service providers. The resulting increased empowerment was hypothesized to increase caretaker involvement, which should affect service use and ultimately the mental health status of the child. A randomized design was used to test the effectiveness of this model with caregivers of children receiving mental health services. The results one-year after the training replicated the intermediate outcomes of the project conducted 3-months after the training. The initial training continued to significantly influence the parent's knowledge and mental health services self-efficacy. However, the intervention had no effect on caregiver involvement in treatment, service use or the mental health status of the children.     

Visual inertia of rotating 3-D objects

Five experiments were designed to determine whether a rotating, transparent 3-D cloud of dots (simulated sphere) could influence the perceived direction of rotation of a subsequent sphere. Experiment 1 established conditions under which the direction of rotation of a virtual sphere was perceived unambiguously. When a near-far luminance difference and perspective depth cues were present, observers consistently saw the sphere rotate in the intended direction. In Experiment 2, a near-far luminance difference was used to create an unambiguous rotation sequence that was followed by a directionally ambiguous rotation sequence that lacked both the near-far luminance cue and the perspective cue. Observers consistently saw the second sequence as rotating in the same direction as the first, indicating the presence of 3-D visual inertia. Experiment 3 showed that 3-D visual inertia was sufficiently powerful to bias the perceived direction of a rotation sequence made unambiguous by a near-far luminance cue. Experiment 5 showed that 3-D visual inertia could be obtained using an occlusion depth cue to create an unambiguous inertia-inducing sequence. Finally, Experiments 2, 4, and 5 all revealed a fast-decay phase of inertia that lasted for approximately 800 msec, followed by an asymptotic phase that lasted for periods as long as 1,600 msec. The implications of these findings are examined with respect to motion mechanisms of 3-D visual inertia.