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Objective Preoperative detection of axillary lymph node metastases (ALNMs) from breast cancer is suboptimal; however, recent work suggests radiomics may improve detection of ALNMs. This study aims to develop a 3D CT radiomics model to improve detection of ALNMs compared to conventional imaging features in patients with locally advanced breast cancer. Methods Retrospective chart review was performed on patients referred to a specialty breast cancer center between 2015 and 2020 with US-guided biopsy-proven ALNMs and pretreatment chest CT. One hundred and twelve patients (224 lymph nodes) met inclusion and exclusion criteria and were assigned to discovery (n = 150 nodes) and testing (n = 74 nodes) cohorts. US-biopsy images were referenced in identifying ALNMs on CT, with contralateral nodes taken as negative controls. Positive and negative nodes were assessed for conventional features of lymphadenopathy as well as for 107 radiomic features extracted following 3D segmentation. Diagnostic performance of individual and combined radiomic features was evaluated. Results The strongest conventional imaging feature of ALNMs was short axis diameter ≥ 10 mm with a sensitivity of 64%, specificity of 95%, and area under the curve (AUC) of 0.89 (95% CI, 0.84-0.94). Several radiomic features outperformed conventional features, most notably energy, a measure of voxel density magnitude. This feature demonstrated a sensitivity, specificity, and AUC of 91%, 79%, and 0.94 (95% CI, 0.91-0.98) for the discovery cohort. On the testing cohort, energy scored 92%, 81%, and 0.94 (95% CI, 0.89-0.99) for sensitivity, specificity, and AUC, respectively. Combining radiomic features did not improve AUC compared to energy alone (P = .08). Conclusion 3D radiomic analysis represents a promising approach for noninvasive and accurate detection of ALNMs. [ABSTRACT FROM AUTHOR]

Surface enhanced infrared absorption (SEIRA) spectroscopy is a powerful tool in which plasmonically enhanced electromagnetic fields provide high‐sensitivity molecular detection. Most SEIRA platforms operate at a single resonant frequency, which must be tuned to match that of the target molecule, and commonly rely on time‐consuming lithographic techniques. This study presents a high‐throughput and cost‐effective plasmonic metasurface for broadband, tunable, and strong infrared signal enhancement. The platform is built upon the principle of dispersion‐engineered plasmonic Fabry–Pérot (FP) nanocavity arrays. It offers 1) tight squeezing of infrared (IR) photons into deep sub‐wavelength nano‐volumes and 2) spectrally tunable near‐field enhancements of up to ≈106, two to three orders of magnitude higher than most optical metasurface systems. By coupling multilayer nano‐thin film deposition and nanoskiving fabrication techniques, the dispersive FP metasurfaces can be rapidly and reproducibly constructed in a scalable and lithography‐free manner. Using IR spectroscopy, the selective and sensitive label‐free detection of a molecular monolayer is achieved at a range of frequencies. An enhancement factor of nearly 105 is measured at the carbonyl (C = O) vibrational marker band of the molecule. The confluence of high field enhancement, broadband plasmonic response, and facile fabrication makes this metasurface a promising platform for SEIRA spectroscopy. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures capable of broadband light trapping and field enhancement have promising applications in a wide range of fields. This study presents a platform for broadband, polarization‐independent field enhancement in the visible regime through the use of width‐graded nanocavities in a bullseye configuration. The fabrication procedure utilizes electron beam lithography (EBL) to achieve fine control over the nanocavity geometry and template stripping to enable rapid and low‐cost production. The utility of these devices as substrates for multi‐wavelength surface enhanced Raman spectroscopy (SERS) is demonstrated through molecular detection in a 10 μM solution at two excitation wavelengths. The impact of bullseye geometry on both the broadband spectral response and multi‐wavelength SERS performance is examined. The measured SERS enhancement factor (EF) is shown to depend primarily on the plasmonically active surface area of the device, regardless of the local electromagnetic field strength within the nanocavities. These results highlight not only the utility of the width‐graded bullseye as a broadband platform for SERS and other applications but also provide design guidelines to optimize the enhancement factor and broadband performance of similar devices. [ABSTRACT FROM AUTHOR]

Characterizing complex biofluids using surface-enhanced Raman spectroscopy (SERS) coupled with machine learning (ML) has been proposed as a powerful tool for point-of-care detection of clinical disease. ML is well-suited to categorizing otherwise uninterpretable, patient-derived SERS spectra that contain a multitude of low concentration, disease-specific molecular biomarkers among a dense spectral background of biological molecules. However, ML can generate false, non-generalizable models when data sets used for model training are inadequate. It is thus critical to determine how different SERS experimental methodologies and workflow parameters can potentially impact ML disease classification of clinical samples. In this study, a label-free, broadband, Ag nanoparticle-based SERS platform was coupled with ML to assess simulated clinical samples for cardiovascular disease (CVD), containing randomized combinations of five key CVD biomarkers at clinically relevant concentrations in serum. Raman spectra obtained at 532, 633, and 785 nm from up to 300 unique samples were classified into physiological and pathological categories using two standard ML models. Label-free SERS and ML could correctly classify randomized CVD samples with high accuracies of up to 90.0% at 532 nm using as few as 200 training samples. Spectra obtained at 532 nm produced the highest accuracies with no significant increase achieved using multiwavelength SERS. Sample preparation and measurement methodologies (e.g., different SERS substrate lots, sample volumes, sample sizes, and known variations in randomization and experimental handling) were shown to strongly influence the ML classification and could artificially increase classification accuracies by as much as 27%. This detailed investigation into the proper application of ML techniques for CVD classification can lead to improved data set acquisition required for the SERS community, such that ML on labeled and robust SERS data sets can be practically applied for future point-of-care testing in patients. [ABSTRACT FROM AUTHOR]

It is very well known that Japan has an extremely low rate of crime compared with other developed countries. Due to fewer serious incidents such as murder, rape, and arson, Japanese society is generally peaceful and orderly. For instance, although there are 23 million juveniles who are younger than 20 years old, only 39 homicides were committed in 2010 in Japan. Most people understand that it is very difficult to reduce crime rates, so how has Japan maintained such a low crime rate? Although there are a number of reasons, the correctional education system for serious juvenile offenders in Japan is worthy of special mention. In this commentary, the author introduces a unique correctional educational facility, Jido-Ziritsu-Shien-Shisetsu (JZSS), that she hopes will provide an interesting glimpse into service provision in Japan. (Contains 1 table.)

Eighty-three inmates of a correctional facility, who committed serious offences, participated in this study. They were all male and aged 14-17 years, with a mean age of 15.5 (SD=1.21) years. Eighty-six age- and sex-matched controls were enrolled. Some psychological questionnaires such as on self-esteem and aggression were conducted in both groups. The aims of the present study were as follows: first, to clarify the characteristics of the subjects, such as IQ, psychological traits, and AD/HD symptoms; second, to examine how the subjects' self-esteem and aggression changed and/or improved on admission and at the time of parole (during the correctional educational period). For the results of paired t-tests, the self-esteem of subjects changed little. Therefore, our findings suggest that the improvement of antisocial behavior and transition of self-esteem are not directly linked with each other. Most inmates of the correctional facility showed a borderline IQ, markedly low self-esteem, unstable aggression, and serious AD/HD symptoms. In addition, the low self-esteem of subjects was not consistently elevated during the correctional education period. Moreover, their aggression was strongly correlated with AD/HD symptoms, both on admission and at the time of parole. (Contains 4 tables.)

The purpose of this study was to clarify the following 2 points: (1) whether self-esteem changes after correctional education, and (2) whether attention deficit/hyperactivity characteristics affect self-esteem. The subjects were 118 juveniles (all males) admitted to "A" juvenile correctional facility. Our findings indicated that during the correctional education period, changes in self-esteem were limited. The AD/HD-YSR attention deficit score was negatively correlated with the self-esteem score on admission but was not associated with the self-esteem score at the time of parole. Next, the subjects were classified according to the self-esteem score. Consequently, the attention deficit score was significantly associated with self-esteem in all groups. Our results were suggested that total AD/HD-YSR score in the high self-esteem group was lower than that in the other groups. Our cross-sectional surveys have shown an association between the AD/HD-YSR score and self-esteem, suggesting the influences of developmental problems on self-esteem. Research implications were discussed. (Contains 3 tables.)

The objective of this article is to address the challenges of physical sample retrieval from all locations along patients' gastrointestinal (GI) tracts for studying of interactions between GI microbial communities (microbiomes) and host immune systems. We propose a novel tetherless, blindly controlled, magnetically actuated capsule for noninvasive sampling of GI microbiomes and liquid digesta. The mesoscale capsule, a soft mobile robot platform, is made from two permanent magnets encapsulated in a soft elastomer and actuated remotely by an external magnet. The capsule is controlled blindly using an external magnet to orient and activate the capsule. Following oral administration, capsules transit the GI tract and are activated at specified locations. The capsule is recovered via routine stool passage and collected samples are processed for downstream analyses (e.g., 16S rRNA surveys, metagenomics, metatranscriptomics and/or metabolomics). The localization of the capsule is estimated using the traveling time and the location of collected microbiomes will be confirmed by downstream analyses. A mathematical model of capsule activation is used to predict capsule activation and guide design optimization. We demonstrate the ability of the capsule to collect samples, as well as maintain sample integrity in vitro, ex vivo, and with twelve capsules in in vivo swine models. Eleven capsules successfully collected digesta (in the range of 18 to 61 mg). This sampling apparatus offers a technological advance for the robust sampling of GI tract contents. [ABSTRACT FROM AUTHOR]

Abstract Background Previous reports have suggested impairment in facial expression recognition in delinquents, but controversy remains with respect to how such recognition is impaired. To address this issue, we investigated facial expression recognition in delinquents in detail. Methods We tested 24 male adolescent/young adult delinquents incarcerated in correctional facilities. We compared their performances with those of 24 age- and gender-matched control participants. Using standard photographs of facial expressions illustrating six basic emotions, participants matched each emotional facial expression with an appropriate verbal label. Results Delinquents were less accurate in the recognition of facial expressions that conveyed disgust than were control participants. The delinquents misrecognized the facial expressions of disgust as anger more frequently than did controls. Conclusion These results suggest that one of the underpinnings of delinquency might be impaired recognition of emotional facial expressions, with a specific bias toward interpreting disgusted expressions as hostile angry expressions.

Aim : A tic‐related specifier is included in the DSM‐5 diagnostic criteria to identify a clinically specific obsessive–compulsive disorder (OCD) subtype. The current study sought to evaluate hemodynamic changes during executive function tasks among OCD patients with and without a lifetime history of tic disorder (TD) and healthy controls, and to investigate the relation between brain activation and clinical variables in each group using structured equation modeling. Methods : Twenty‐nine OCD patients diagnosed according to the DSM‐IV‐TR and 15 healthy controls were recruited. Patients were divided into two groups according to the presence or absence of a lifetime history of TD (TD+, n = 11; TD−, n = 18). Prefrontal hemodynamic changes were measured using multi‐channel near‐infrared spectroscopy during the Verbal Fluency Task, Trail‐Making Task, and Tower of London (ToL) Task. Results : There were significant brain activation differences in the frontopolar cortex between OCD patients with and without TD during Verbal Fluency Task and ToL performance. Brain activation in the dorsolateral prefrontal cortex (DLPFC) during the ToL Task in OCD patients with TD exerted a direct causal effect on the severity of compulsions. In addition, we detected a direct causal effect of the severity of obsessions in OCD patients without TD on brain activation in the DLPFC during the ToL Task. Conclusion : Brain activation in the frontopolar cortex exhibits different hemodynamics depending on the task, and DLPFC function may play a different role in the neural basis of developing OCD symptoms between OCD patients with and without TD. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effects of correctional education on juvenile delinquents at a children's self‐reliance support facility in Japan, which provides delinquents with familial environments and multidimensional, comprehensive education. The purpose of this study was to compare the youth's academic performance and resilience from the time of admission to discharge and to identify which interventions improved participants' academic performance and resilience. We examined juvenile database records and "juvenile diaries" of 283 male youth. Participants were categorized into either an Improvement Group (IG) or a No‐Improvement Group (No‐IG) based on their outcome at discharge. The results showed that their academic performance and resilient characteristics were significantly higher at discharge than at admission. Employing single logistic regression, we found that the length of stay, academic performance, and the number of visits by family and social workers were characteristics associated with membership in the IG. These findings can guide future clinical practices and measures implemented for juvenile delinquents. [ABSTRACT FROM AUTHOR]

Ferroelectric Ba0.7Sr0.3TiO3 films were fabricated using a PbO-doped barium strontium titanate sol-gel precursor. Ba0.7Sr0.3TiO3 thin films with 0, 10, 20, and 30 at.%PbO doping were deposited on bare silicon, and platinum coated silicon substrates, using spin coating. The influence of PbO doping both on the film microstructure and properties was studied. Doping in excess of 20 at.%PbO was found to markedly decrease film porosity, while enhancing crystallization by decreasing the annealing temperature required for the formation of the perovskite phase from above 650 °C to 500 °C. Electrical characterization of the films demonstrated their excellent properties for electronic device application. Films with 20 at.%PbO doping had room temperature dielectric constant and dissipation factor of 268 and 0.95%, respectively (measured at 10 kHz), with tunability from 30% to 75% and commutation quality factor in excess of 105 (for bias field from 200 to 800 kV/cm). Room temperature leakage current were measured to be as low as 2.45×10-9 A/cm2 (at bias field of 250 kV/cm). [ABSTRACT FROM AUTHOR]

Ferroelectric Ba0.7Sr0.3TiO3 films are fabricated using a PbO-doped barium strontium titanate sol-gel precursor. The findings show that doping in excess of 20 at. % PbO is found to markedly decrease film porosity, while enhancing crystallization by decreasing the annealing temperature required for the formation of the perovskite phase form above 650 degree C to 500 degree C.

Aim: Obsessive–compulsive disorder (OCD) is a well‐known chronic illness. This study retrospectively investigated 10‐year outcomes and associated clinical factors in Japanese OCD patients. We focused on the impact of several sociocultural factors, including medical expenses and insurance systems specific to each country, on the differences or biases in follow‐up procedures of OCD. Methods: Seventy‐nine patients diagnosed with OCD who received a standardized combination of treatments for 10 continuous years were divided into three groups according to their improvement rates on the Yale–Brown Obsessive–Compulsive Scale after 10 years of treatment. Results: A survival analysis revealed that the rate of patients achieving full remission increased every year. Following 10 years of treatment, 56% of OCD patients experienced ‘full remission’ for at least 1 year. Consequently, 48% exhibited full remission, and 37% exhibited partial remission at the end‐point of this study. We identified several factors that were predictive of poorer outcomes, including lower Global Assessment of Functioning Scale scores and the presence of hoarding symptoms or involvement behaviors. In addition, improvement rates after 1 year significantly predicted better 10‐year outcomes. Conclusion: Our findings highlight the transcultural nature of long‐term outcomes of OCD treatment, which appear to be independent of sociocultural differences. [ABSTRACT FROM AUTHOR]

Abstract: Plasmonic gratings of rectangular groove profile with gradient in the groove width perform as unique surface‐enhanced Raman spectroscopy (SERS) substrates by simultaneously confining multiple laser wavelengths proximally and inside their rectangular nanotrenches. These gratings consist of a metal–insulator–metal (MIM) groove of 40 nm width at the center, surrounded by grooves with widths increasing in 10 nm steps to a maximum of 180 nm. It is experimentally shown and theoretically confirmed that upon illumination a maximally enhanced electromagnetic field is generated at the center of these gratings as a result of plasmonic light trapping as well as waveguiding produced by the surrounding grooves. SERS enhancement factors of 106–107 are demonstrated for 20 μL min−1 flow of 1 × 10−3 m aqueous phospholipid solution using 532, 638, and 785 nm laser illumination of the gratings integrated within microfluidic devices. These robust multiwavelength SERS substrates offer highly reproducible plasmonic field enhancement that can be tuned to cover broad wavelength ranges within the visible and near‐infrared regime and are ideal for static and dynamic characterization of low concentration species. Further, the multispectral characteristic of these gratings facilitates multiplexing through various laser wavelengths thereby making it possible to readily access weak or silent Raman modes. [ABSTRACT FROM AUTHOR]

Previous studies provide clear evidence that visuospatial memory performance in children with attention-deficit/hyperactivity disorder (ADHD) is significantly lower than in typically developing children. In the present study, we investigated a major cause of their low performance using a spatial span test. Possibly, inattention resulting from lack of motivation or interest causes their low performance so that they do not correctly encode targets to be remembered. On the other hand, a deficit in temporary maintenance per se may cause their low performance; that is, their inefficient use of rehearsal during a retention interval may lead to memory traces’ fast decay. Results in this study indicated that children with ADHD could sustain attention during the encoding phase. Furthermore, their performance at delayed recall was significantly lower than immediate recall, but delayed recall did not affect typically developing children's performance. These results provide evidence for the likelihood that a factor causing children with ADHD difficulty in temporarily maintaining visuospatial information is fast decay of memory traces as a result of inefficient use of rehearsal, not inattention in the encoding phase. [ABSTRACT FROM PUBLISHER]

Continued advances in the field of ultrasound and ultrasound contrast agents have created new approaches to imaging and medical intervention. Phase-shift perfluorocarbon droplets, which can be vaporized by ultrasound energy to transition from the liquid to the vapor state, are one of the most highly researched alternatives to clinical ultrasound contrast agents (i.e., microbubbles). In this paper, part of a special issue on methods in biomedical ultrasonics, we survey current techniques to prepare ultrasound-activated nanoscale phase-shift perfluorocarbon droplets, including sonication, extrusion, homogenization, microfluidics, and microbubble condensation. We provide example protocols and discuss advantages and limitations of each approach. Finally, we discuss best practice in characterization of this class of contrast agents with respect to size distribution and ultrasound activation. [ABSTRACT FROM PUBLISHER]

Perfluorocarbon (PFC) nanodroplet agents are exciting new biomaterials that can be remotely vapourized by ultrasound or light to change into micron-scale gas bubbles in situ. After PFC nanodroplet vapourization, the micron-scale gas bubble can interact strongly with ultrasound radiation, such that the bubbles can be used for cancer imaging and therapy. For these phase-change agents to be useful, however, PFC nanodroplets must be produced in the range of 100 to 400 nm in diameter with high size control and monodispersity, restrictions that remain a challenge. Here, we address this challenge by taking advantage of the size control offered by microfluidics, in combination with the size reduction provided by cosolvent-infused PFC bubbles through both condensation and cosolvent dissolution. In this approach, PFC bubbles with a high percentage of cosolvent (in this study, diethyl ether, DEE) are produced using microfluidics at a temperature above the boiling point. After synthesis, these bubbles become much smaller through both condensation of the gas into liquid droplets and from dissolution of the DEE into the continuous phase. This approach demonstrates that monodisperse, cosolvent-incorporated PFC bubbles can directly form monodisperse PFC nanodroplets a factor of 24 times smaller than the precursor bubbles. We also demonstrate that these nanoscale droplets can be converted to echogenic microbubbles after exposure to ultrasound, showing that these PFC nanodroplets are viable for the in situ production of ultrasound contrast agents. We show that this system can overcome the minimum droplet size limit of standard microfluidics, and is a powerful new tool for generating monodisperse, PFC phase-change ultrasound contrast agents for treating and imaging cancer. [ABSTRACT FROM AUTHOR]

Background A wide range of evidence supports the methylphenidate (MPH)-induced enhancement of prefrontal cortex (PFC) functioning and improvements in behavioral symptoms in patients with attention deficit hyperactivity disorder (ADHD). Although working memory (WM) has been hypothesized to be impaired in patients with ADHD, no pharmacological studies have examined visuospatial WM (VSWM) with near-infrared spectroscopy (NIRS). Study aim The present study was designed to investigate the acute effects of MPH on neuropsychological performance and hemodynamic activation in children with ADHD during VSWM tasks. Methods The subject group included 10 boys and 1 girl previously diagnosed with ADHD. Two VSWM tasks of differing degrees of difficulty were conducted. This is the first study on the pharmacological effects of MPH in children with ADHD to evaluate hemodynamic responses in the PFC with simultaneous NIRS. Results No significant differences were found in the scores for both spatial working memory (SWM) and score of spatial span (SSP) tasks between the MPH-off and MPH?on conditions. However, a significant MPH-effect on changes in oxy-hemoglobin levels in the PFC was found only in the SWM task. Conclusion These findings suggest that PFC activation might be affected by MPH, depending on the degree of difficulty of the particular task. Although the MPH-induced change on behavior may or may not be obvious, NIRS measurements might be useful for assessing the psychological effects of MPH even when performance changes were not observed in the cognitive tasks. [ABSTRACT FROM AUTHOR]

Contrast-enhanced digital mammography (CEDM) can provide improved breast cancer detection and characterization compared to conventional mammography by imaging the effects of tumour angiogenesis. Current smallmolecule contrast agents used for CEDM are limited by a short plasma halflife and rapid extravasation into tissue interstitial space. To address these limitations, nanoscale agents that can remain intravascular except at sites of tumour angiogenesis can be used. For CEDM, this agent must be both biocompatible and strongly attenuatemammographic energy x-rays.Nanoscale perfluorooctylbromide (PFOB) droplets have good x-ray attenuation and have been used in patients for other applications. However, the macroscopic scale of x-ray imaging (50-100 μm) is inadequate for direct verification that PFOB droplets localize at sites of breast tumour angiogenesis. For efficient pre-clinical optimization for CEDM, we integrated an optical marker into PFOB droplets for microscopic assessment (⪡50 μm). To develop PFOB droplets as a new nanoscale mammographic contrast agent, PFOB droplets were labelled with fluorescent quantum dots (QDs). The droplets had mean diameters of 160 nm, fluoresced at 635 nm and attenuated x-ray spectra at 30.5 keV mean energy with a relative attenuation of 5.6 ± 0.3 Hounsfield units (HU) mg-1 mL-1 QDPFOB. With the agent loaded into tissue phantoms, good correlation between x-ray attenuation and optical fluorescence was found (R2 = 0.96), confirming co-localization of the QDs withPFOBfor quantitative assessment using x-ray or optical methods. Furthermore, the QDs can be removed from the PFOB agent without affecting its x-ray attenuation or structural properties for expedited translation of optimized PFOB droplet formulations into patients. [ABSTRACT FROM AUTHOR]

Background: Identification of gene × environment interactions (G × E) for depression is a crucial step in ascertaining the mechanisms underpinning the disorder. Earlier studies have indicated strong genetic influences and numerous environmental risk factors. In relation to childhood and adolescent depression, evidence is accumulating that the quality of the parental environment is associated with serotonin biology in children. We hypothesized that maternal depression is a crucial environmental risk factor associated with serotonin-regulating genes. Methods: This study was designed to ascertain the G × E interaction for diagnosis of depression in a Japanese pediatric sample. DNA samples from 55 pediatric patients with depression and 58 healthy schoolchildren were genotyped for the 5-HTT (2 short (S) alleles at the 5-HTT locus) promoter serotonin-transporter-linked polymorphic region (5-HTTLPR) polymorphism. We examined whether an adverse parental environment, operationalized as the mother's history of recurrent major depressive disorder, interacts with 5-HTTLPR polymorphism to predict patients' depression symptoms. Results: Binary logistic regression analyses revealed that maternal depression (adversity), gender, and FSIQ significantly affect the diagnosis of depression among children and adolescents. However, no main effect was found for adversity or genotype. Results of multivariable logistic regression analyses using stepwise procedure have elicited some models with a good fit index, which also suggests no interaction between 5-HTTLPR and adversity on depression. Conclusions: To assess G × E interaction, data obtained from children and adolescents who had been carefully diagnosed categorically and data from age-matched controls were analyzed using logistic regression. Despite an equivocal interaction effect, adversity and gender showed significant main effects [ABSTRACT FROM AUTHOR]

Female juvenile offenders are more likely to have a history of childhood abuse, emotional disturbances, mental health problems, and serious problems involving substance abuse. The aim of this study were: (1) to investigate the characteristics of self-esteem, aggressiveness, depressiveness, and adverse childhood experiences (ACEs), (2) to examine the relationships of these characteristics between female inmates of a juvenile correctional facility and age- and gender-matched controls, and (3) to propose an appropriate cause–effect relation model using structural equal modeling. The subjects were 81 female juveniles admitted to a female juvenile correctional facility and 285 age- and sex-matched comparisons. There was clear evidence for strong relationship between ACEs, aggression, depression, and low self-esteem. In addition, path analysis by structural equation modeling showed a simple clear model diagram regarding self-esteem in the female juvenile offenders. [ABSTRACT FROM AUTHOR]

The authors investigated whether impaired spatial short-term memory exhibited by children with nonverbal learning disabilities is due to a problem in the encoding process. Children with or without nonverbal learning disabilities performed a simple spatial test that required them to remember 3, 5, or 7 spatial items presented simultaneously in random positions (i.e., spatial configuration) and to decide if a target item was changed or all items including the target were in the same position. The results showed that, even when the spatial positions in the encoding and probe phases were similar, the mean proportion correct of children with nonverbal learning disabilities was 0.58 while that of children without nonverbal learning disabilities was 0.84. The authors argue with the results that children with nonverbal learning disabilities have difficulty encoding relational information between spatial items, and that this difficulty is responsible for their impaired spatial short-term memory. [ABSTRACT FROM AUTHOR]