The link between working memory and fluid intelligence is dependent on flexible bindings, not systematic access or passive retention.

Rather than working memory capacity acting as a distinct subordinate function of fluid intelligence, there is an emerging consensus that their relationship can be understood as an outcome of common functions dictated by the strength and flexibility of bindings which integrate representations relationally. The current study considers the Arithmetic Chain Task (Oberauer, Demmrich, Mayr, & Kliegl, 2001) which contrasts access (integrating previously stored information for use in the arithmetic processing) against mere retention (holding previously stored information for recall after the arithmetic processing). Participants (n = 122) completed the Arithmetic Chain Task (ACT) with a novel manipulation that split the access condition into fixed-order vs. random-order access. Both forms of access require integration of previously stored information into the arithmetic, but random-order access restricts systematic chunking, necessitating multiple flexible bindings that can be updated in light of new information. Participants also completed a measure of working memory and a measure of fluid intelligence. Results replicated Oberauer et al.'s findings on a demarcation between retention and access, though the current data indicate that random-order presentation is necessary to distinguish access from retention. Crucially, this random-order access is also required to link the ACT to a factor representing the commonality in WM and Gf. These results suggest that what is common to WM and Gf is the capacity to maintain multiple durable and flexible bindings.

Validating the relation-monitoring task as a measure of relational integration and predictor of fluid intelligence.

The relation-monitoring task (RMT) has demonstrated a remarkable ability to predict higher-order cognitive abilities such as fluid intelligence, despite its apparent simplicity: It requires no storage over time and no advanced mental manipulation. Instead, the task is theorized to measure relational integration: the process of constructing mental relations between independent elements. Although several studies have established a link between the RMT and fluid intelligence, few studies have investigated the task parameters that contribute to the task's ability to predict higher-order performance. In the present experiment, we manipulated relational complexity and attentional-control demands by varying visual interference and the amount of new information presented on each trial. Even the most basic version of the task (loading primarily on relational integration) explained substantial variance in fluid intelligence, above and beyond the variance already predicted by traditional working memory tasks. We extended prior results by suggesting an incremental effect of attentional-control demands that contributes (but is not imperative) to the RMT's relationship with fluid intelligence. These findings support the relational integration hypothesis, the theory that what fundamentally limits fluid intelligence is the capacity for relational integration.

Correction: Relational encoding of objects in working memory: Changes detection performance is better for violations in group relations.

[This corrects the article DOI: 10.1371/journal.pone.0203848.].

Relational encoding of objects in working memory: Change detection performance is better for violations in group relations.

Research has indicated that working memory is based on forming relations between individual elements. In this study, we considered the congruency of object clusters during a change detection task. We demonstrate that changes which violate the relational encoding of a probe display (single-object changes where one object shifts independently from its corresponding group) are more easily detected than changes that maintain group structure (cluster changes where all objects in the group shift in location together)-despite cluster changes involving more objects moving overall. We explore this effect across interactions with direction of single-object movement (distancing from the cluster vs. uniting with the cluster) and trial order, demonstrating that naïve participants improve at a faster rate on single-object changes than cluster changes. It is concluded that storage in working memory functions by building relational bindings between objects and their place within the chunk, rather than by binding objects to their spatial location.

Toward Precision Medicine for Neurological and Neuropsychiatric Disorders.

The genetic complexity, clinical variability, and inaccessibility of affected tissue in neurodegenerative and neuropsychiatric disorders have largely prevented the development of effective disease-modifying therapeutics. A precision medicine approach that integrates genomics, deep clinical phenotyping, and patient stem cell models may facilitate identification of underlying biological drivers and targeted drug development.

Meta-Analysis of the Effects of Computerized Cognitive Training on Executive Functions: a Cross-Disciplinary Taxonomy for Classifying Outcome Cognitive Factors.

The growing prevalence of neurodegenerative disorders associated with aging and cognitive decline has generated increasing cross-disciplinary interest in non-pharmacological interventions, such as computerized cognitive training (CCT), which may prevent or slow cognitive decline. However, inconsistent findings across meta-analytic reviews in the field suggest a lack of cross-disciplinary consensus and on-going debate regarding the benefits of CCT. We posit that a contributing factor is the lack of a theoretically-based taxonomy of constructs and representative tasks typically used. An integration of the Cattell-Horn-Carroll (CHC) taxonomy of broad and narrow cognitive factors and the Miyake unity-diversity theory of executive functions (EF) is proposed (CHC-M) as an attempt to clarify this issue through representing and integrating the disciplines contributing to CCT research. The present study assessed the utility of this taxonomy by reanalyzing the Lampit et al. (2014) meta-analysis of CCT in healthy older adults using the CHC-M framework. Results suggest that: 1) substantively different statistical effects are observed when CHC-M is applied to the Lampit et al. meta-analytic review, leading to importantly different interpretations of the data; 2) typically-used classification practices conflate Executive Function (EF) tasks with fluid reasoning (Gf) and retrieval fluency (Gr), and Attention with sensory perception; and 3) there is theoretical and practical advantage in differentiating attention and working-memory tasks into the narrow shifting, inhibition, and updating EF domains. Implications for clinical practice, particularly for our understanding of EF are discussed.

Systemic cell cycle activation is induced following complex tissue injury in axolotl.

Activation of progenitor cells is crucial to promote tissue repair following injury in adult animals. In the context of successful limb regeneration following amputation, progenitor cells residing within the stump must re-enter the cell cycle to promote regrowth of the missing limb. We demonstrate that in axolotls, amputation is sufficient to induce cell-cycle activation in both the amputated limb and the intact, uninjured contralateral limb. Activated cells were found throughout all major tissue populations of the intact contralateral limb, with internal cellular populations (bone and soft tissue) the most affected. Further, activated cells were additionally found within the heart, liver, and spinal cord, suggesting that amputation induces a common global activation signal throughout the body. Among two other injury models, limb crush and skin excisional wound, only limb crush injuries were capable of inducing cellular responses in contralateral uninjured limbs but did not achieve activation levels seen following limb loss. We found this systemic activation response to injury is independent of formation of a wound epidermis over the amputation plane, suggesting that injury-induced signals alone can promote cellular activation. In mammals, mTOR signaling has been shown to promote activation of quiescent cells following injury, and we confirmed a subset of activated contralateral cells is positive for mTOR signaling within axolotl limbs. These findings suggest that conservation of an early systemic response to injury exists between mammals and axolotls, and propose that a distinguishing feature in species capable of full regeneration is converting this initial activation into sustained and productive growth at the site of regeneration.

A Tissue-Mapped Axolotl De Novo Transcriptome Enables Identification of Limb Regeneration Factors.

Mammals have extremely limited regenerative capabilities; however, axolotls are profoundly regenerative and can replace entire limbs. The mechanisms underlying limb regeneration remain poorly understood, partly because the enormous and incompletely sequenced genomes of axolotls have hindered the study of genes facilitating regeneration. We assembled and annotated a de novo transcriptome using RNA-sequencing profiles for a broad spectrum of tissues that is estimated to have near-complete sequence information for 88% of axolotl genes. We devised expression analyses that identified the axolotl orthologs of cirbp and kazald1 as highly expressed and enriched in blastemas. Using morpholino anti-sense oligonucleotides, we find evidence that cirbp plays a cytoprotective role during limb regeneration whereas manipulation of kazald1 expression disrupts regeneration. Our transcriptome and annotation resources greatly complement previous transcriptomic studies and will be a valuable resource for future research in regenerative biology.

The effectiveness of family-based treatment for full and partial adolescent anorexia nervosa in an independent private practice setting: Clinical outcomes.

OBJECTIVE: Anorexia nervosa (AN) is a severe psychiatric illness with little evidence supporting treatment in adults. Among adolescents with AN, family-based treatment (FBT) is considered first-line outpatient approach, with a growing evidence base. However, research on FBT has stemmed from specialist services in research/public health settings. This study investigated the effectiveness of FBT in a case series of adolescent AN treated in a private practice setting. METHOD: Thirty-four adolescents with full or partial AN, diagnosed according to DSM-IV criteria, participated, and were assessed at pretreatment and post-treatment. Assessments included change in % expected body weight, mood, and eating pathology. RESULTS: Significant weight gain was observed from pretreatment to post-treatment. 45.9% of the sample demonstrated full weight restoration and a further 43.2% achieved partial weight-based remission. Missing data precluded an examination of change in mood and ED psychopathology. DISCUSSION: Effective dissemination across different service types is important to the wider availability of evidence-based treatments. These weight restoration data lend preliminary support to the implementation of FBT in real world treatment settings. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:1023-1026).