Targeted density electrode placement achieves high concordance with traditional high-density EEG for electrical source imaging in epilepsy.

OBJECTIVE: High-density (HD) electroencephalography (EEG) is increasingly used in presurgical epilepsy evaluation, but it is demanding in time and resources. To overcome these issues, we compared EEG source imaging (ESI) solutions with a targeted density and HD-EEG montage. METHODS: HD-EEGs from patients undergoing presurgical evaluation were analyzed. A low-density recording was created by selecting the 25 electrodes of a standard montage from the 83 electrodes of the HD-EEG and adding 8-11 electrodes around the electrode with the highest amplitude interictal epileptiform discharges. The ESI solution from this "targeted" montage was compared to that from the HD-EEG using the distance between peak vertices, sublobar concordance and a qualitative similarity measure. RESULTS: Fifty-eight foci of forty-three patients were included. The median distance between the peak vertices of the two montages was 13.2 mm, irrespective of focus' location. Tangential generators (n = 5/58) showed a higher distance than radial generators (p = 0.04). We found sublobar concordance in 54/58 of the foci (93%). Map similarity, assessed by an epileptologist, had a median score of 4/5. CONCLUSIONS: ESI solutions obtained from a targeted density montage show high concordance with those calculated from HD-EEG. SIGNIFICANCE: Requiring significantly fewer electrodes, targeted density EEG allows obtaining similar ESI solutions as traditional HD-EEG montage.

Neurocognitive basis of model-based decision making and its metacontrol in childhood.

Human behavior is supported by both goal-directed (model-based) and habitual (model-free) decision-making, each differing in its flexibility, accuracy, and computational cost. The arbitration between habitual and goal-directed systems is thought to be regulated by a process known as metacontrol. However, how these systems emerge and develop remains poorly understood. Recently, we found that while children between 5 and 11 years displayed robust signatures of model-based decision-making, which increased during this developmental period, there were substantial individual differences in the display of metacontrol. Here, we inspect the neurocognitive basis of model-based decision-making and metacontrol in childhood and focus this investigation on executive functions, fluid reasoning, and brain structure. A total of 69 participants between the ages of 6-13 completed a two-step decision-making task and an extensive behavioral test battery. A subset of 44 participants also completed a structural magnetic resonance imaging scan. We find that individual differences in metacontrol are specifically associated with performance on an inhibition task and individual differences in thickness of dorsolateral prefrontal, temporal, and superior-parietal cortices. These brain regions likely reflect the involvement of cognitive processes crucial to metacontrol, such as cognitive control and contextual processing.

Coordinated cortical thickness alterations across six neurodevelopmental and psychiatric disorders.

Neuropsychiatric disorders are increasingly conceptualized as overlapping spectra sharing multi-level neurobiological alterations. However, whether transdiagnostic cortical alterations covary in a biologically meaningful way is currently unknown. Here, we studied co-alteration networks across six neurodevelopmental and psychiatric disorders, reflecting pathological structural covariance. In 12,024 patients and 18,969 controls from the ENIGMA consortium, we observed that co-alteration patterns followed normative connectome organization and were anchored to prefrontal and temporal disease epicenters. Manifold learning revealed frontal-to-temporal and sensory/limbic-to-occipitoparietal transdiagnostic gradients, differentiating shared illness effects on cortical thickness along these axes. The principal gradient aligned with a normative cortical thickness covariance gradient and established a transcriptomic link to cortico-cerebello-thalamic circuits. Moreover, transdiagnostic gradients segregated functional networks involved in basic sensory, attentional/perceptual, and domain-general cognitive processes, and distinguished between regional cytoarchitectonic profiles. Together, our findings indicate that shared illness effects occur in a synchronized fashion and along multiple levels of hierarchical cortical organization.

Association between hippocampal structure and serum Brain-Derived Neurotrophic Factor (BDNF) in healthy adults: A registered report.

The hippocampus is a highly plastic brain structure supporting functions central to human cognition. Morphological changes in the hippocampus have been implicated in development, aging, as well as in a broad range of neurological and psychiatric disorders. A growing body of research suggests that hippocampal plasticity is closely linked to the actions of brain-derived neurotrophic factor (BDNF). However, evidence on the relationship between hippocampal volume (HCV) and peripheral BDNF levels is scarce and limited to elderly and patient populations. Further, despite evidence that BDNF expression differs throughout the hippocampus and is implicated in adult neurogenesis specifically in the dentate gyrus, no study has so far related peripheral BDNF levels to the volumes of individual hippocampal subfields. Besides its clinical implications, BDNF-facilitated hippocampal plasticity plays an important role in regulating cognitive and affective processes. In the current registered report, we investigated how serum BDNF (sBDNF) levels relate to volumes of the hippocampal formation and its subfields in a large sample of healthy adults (N = 279, 160 f) with a broad age range (20-55 years, mean 40.5) recruited in the context of the ReSource Project. We related HCV to basal sBDNF and, in a subsample (n = 103, 57 f), to acute stress-reactive change in sBDNF. We further tested the role of age as a moderator of both associations. Contrary to our hypotheses, neither basal sBDNF levels nor stress-reactive sBDNF change were associated with total HCV or volume of the dentate gyrus/cornu ammonis 4 (DG/CA4) subfield. We also found no evidence for a moderating effect of age on any of these associations. Our null results provide a first point of reference on the relationship between sBDNF and HCV in healthy mid-age, in contrast to patient or aging populations. We suggest that sBDNF levels have limited predictive value for morphological differences of the hippocampal structure when notable challenge to its neuronal integrity or to neurotrophic capacity is absent.

Left dorsolateral prefrontal cortex supports context-dependent prioritisation of off-task thought.

When environments lack compelling goals, humans often let their minds wander to thoughts with greater personal relevance; however, we currently do not understand how this context-dependent prioritisation process operates. Dorsolateral prefrontal cortex (DLPFC) maintains goal representations in a context-dependent manner. Here, we show this region is involved in prioritising off-task thought in an analogous way. In a whole brain analysis we established that neural activity in DLPFC is high both when 'on-task' under demanding conditions and 'off-task' in a non-demanding task. Furthermore, individuals who increase off-task thought when external demands decrease, show lower correlation between neural signals linked to external tasks and lateral regions of the DMN within DLPFC, as well as less cortical grey matter in regions sensitive to these external task relevant signals. We conclude humans prioritise daydreaming when environmental demands decrease by aligning cognition with their personal goals using DLPFC.

Review: Neurodegenerative processes in temporal lobe epilepsy with hippocampal sclerosis: Clinical, pathological and neuroimaging evidence.

Cognitive decline is increasingly described as a co-morbidity of temporal lobe epilepsy (TLE). Mechanisms underlying cognitive impairment are not fully understood despite examining clinical factors, such as seizure frequency, and cellular mechanisms of excitotoxicity. We review the neuropsychometry evidence for progressive cognitive decline and examine the pathology and neuroimaging evidence supporting a neurodegenerative process in hippocampal sclerosis (HS)-related TLE. Accelerated cognitive decline is described in groups of adult HS-related TLE patients. Large childhood studies show early onset of seizures result in poor development of verbal memory and a hindrance in achieving cognitive potential. We discuss HS classification according to different patterns of neuronal loss and correlation to post-temporal lobectomy cognitive outcomes in refractory TLE patients. Factors such as lateralization of HS pathology, neuronal density and subtype have correlated to cognitive outcomes with varying significance between different studies. Furthermore, alterations in neuronal maturity, regenerative capacity and aberrant connectivity appear to affect cognitive performance post-operatively suggesting a complex multifactorial process. More recent studies have identified tau pathology being present in HS-related TLE and correlated to post-operative cognitive decline in some patients. A traumatic head injury-related or novel tauopathy has been hypothesized as an underlying process. We discuss the value of prospective and cross-sectional imaging in assessing cognition and review volumetric magnetic resonance studies with progressive ipsilateral hippocampal atrophy identified to correlate with seizure frequency. Finally, we consider the use of positron emission tomography biomarkers, such as tau tracers, and connectivity studies that may examine in vivo pathways and further explore cognitive decline in TLE.

Expert Knowledge Influences Decision-Making for Couples Receiving Positive Prenatal Chromosomal Microarray Testing Results.

To assess how participants receiving abnormal prenatal genetic testing results seek information and understand the implications of results, 27 US female patients and 12 of their male partners receiving positive prenatal microarray testing results completed semi-structured phone interviews. These interviews documented participant experiences with chromosomal microarray testing, understanding of and emotional response to receiving results, factors affecting decision-making about testing and pregnancy termination, and psychosocial needs throughout the testing process. Interview data were analyzed using a modified grounded theory approach. In the absence of certainty about the implications of results, understanding of results is shaped by biomedical expert knowledge (BEK) and cultural expert knowledge (CEK). When there is a dearth of BEK, as in the case of receiving results of uncertain significance, participants rely on CEK, including religious/spiritual beliefs, "gut instinct," embodied knowledge, and social network informants. CEK is a powerful platform to guide understanding of prenatal genetic testing results. The utility of culturally situated expert knowledge during testing uncertainty emphasizes that decision-making occurs within discourses beyond the biomedical domain. These forms of "knowing" may be integrated into clinical consideration of efficacious patient assessment and counseling.

Kuwaiti Arabic: acquisition of singleton consonants.

BACKGROUND: Arabic, a Semitic language of the Afro-Asiatic variety, has a rich consonant inventory. Previous studies on Arabic phonological acquisition have focused primarily on dialects in Jordan and Egypt. Because Arabic varies considerably across regions, information is also needed for other dialects. AIMS: To determine acquisition benchmarks for singleton consonants for Kuwaiti Arabic-speaking 4-year-olds. METHODS & PROCEDURES: Participants were 80 monolingual Kuwaiti Arabic-speaking children divided into two age groups: 46-54 and 55-62 months. Post-hoc, eight children were identified as possibly at risk for protracted phonological development. A native Kuwaiti Arabic speaker audio-recorded and transcribed single-word speech samples (88 words) that tested consonants across word positions within a variety of word lengths and structures. Transcription reliability (point-to-point) was 95% amongst the authors, and 87% with an external consultant. Three acquisition levels were designated that indicated the proportion of children with no mismatches ('errors') for a given consonant: 90%+ of children, 75-89%, fewer than 75%. Mismatch patterns were described in terms of a phonological feature framework previously described in the literature. OUTCOMES & RESULTS: The Kuwaiti 4-year-olds produced many singleton consonants accurately, including pharyngeals and uvulars. Although the older age group had fewer manner and laryngeal mismatches than the younger age group, consonants still developing at age 5 included coronal fricatives and affricates, trilled /r/ and some uvularized consonants ('emphatics'). The possible at-risk group showed mastery of fewer consonants than the other children. By feature category, place mismatches were the most common, primarily de-emphasis and lack of contrast for [coronal, grooved] (distinguishing alveolar from interdental fricatives). Manner mismatches were next most common: the most frequent substitutions were [+lateral] [l] or other rhotics for /r/, and stops for fricatives. Laryngeal mismatches were few, and involved partial or full devoicing. Group differences generally reflected proportions of mismatches rather than types. CONCLUSIONS & IMPLICATIONS: Compared with studies for Jordanian and Egyptian Arabic, Kuwaiti 4-year-olds showed a somewhat more advanced consonant inventory than same age peers, especially with respect to uvulars, pharyngeals and uvularized (emphatic) consonants. Similar to the other studies, consonant categories yet to master were: [+trilled] /r/, coronal fricative feature [grooved], [+voiced] fricatives /ʕ, z/ and the affricate /d͡͡ʒ/ and some emphatics. Common mismatch patterns generally accorded with previous studies. This study provides criterion reference benchmarks for Kuwaiti Arabic consonant singleton acquisition in 4-year-olds.

Phonological assessment and analysis tools for Tagalog: Preliminary development.

Information and assessment tools concerning Tagalog phonological development are minimally available. The current study thus sets out to develop elicitation and analysis tools for Tagalog. A picture elicitation task was designed with a warm-up, screener and two extension lists, one with more complex and one with simpler words. A nonlinear phonological analysis form was adapted from English (Bernhardt & Stemberger, 2000) to capture key characteristics of Tagalog. The tools were piloted on a primarily Tagalog-speaking 4-year-old boy living in a Canadian-English-speaking environment. The data provided initial guidance for revision of the elicitation tool (available at phonodevelopment.sites.olt.ubc.ca). The analysis provides preliminary observations about possible expectations for primarily Tagalog-speaking 4-year-olds in English-speaking environments: Lack of mastery for tap/trill 'r', and minor mismatches for vowels, /l/, /h/ and word stress. Further research is required in order to develop the tool into a norm-referenced instrument for Tagalog in both monolingual and multilingual environments.

A Case Study on Vocal Loudness With a Young Adult With Autism Spectrum Disorder and Developmental Delay.

PURPOSE: This clinical focus article describes an exploratory case study addressing reduction of vocal loudness in a young adult with a history of autism spectrum disorder and developmental delay. The need for a short-term pullout individual intervention arose from his participation in the Advancing Language and Literacy group, a program that provides support for enhancement of speech, language, and literacy skills for young adults with developmental disabilities. METHOD: The participant attended individual treatment sessions weekly for 9 sessions, all of which were digitally audio-recorded. Client awareness of different loudness levels was first established using nonspeech sounds and speech samples. Loudness in spontaneous speech was monitored with support of verbal and visual feedback in the individual sessions and tracked in individual sessions as well as sessions of the Advancing Language and Literacy group, which served as a generalization context. RESULTS: In the individual sessions, the participant's spontaneous production of acceptable volume improved from 42% to 92% of utterances. Observation of group participation indicated generalization, with the majority of utterances produced posttreatment at an acceptable volume. CONCLUSIONS: This clinical focus article emphasizes suprasegmental aspects as a dimension of communicative competence and highlights the need for continued intervention research and services for young adults with developmental disabilities.

Evaluation of multisyllabic word production in Canadian English- or French-speaking children within a non-linear phonological framework.

Currently, there is no theoretically justified, evidence-based metric for evaluating segmental and prosodic components of multisyllabic words (MSWs). A pilot study evaluated a MSW metric embedded in non-linear phonological- and language-processing frameworks. Six MSWs were analyzed in 10 Canadian English-speaking 5-year-olds with typically developing speech, and eight French-speaking children, ages 3-4 years, with protracted phonological development (PPD). Mismatches were tallied (with and without vowels), with totals ranked by word and participant, then compared with ranks from Phonological Mean Length of Utterance (PMLU) and Percent Consonants Correct (PCC) tallies. For both groups, the number of different ranks was significant in comparisons of MSW metrics with PMLU and PCC. Rank orderings were systematically higher for English-speaking children using the MSW metric, with/without vowels, and for French-speaking children using the MSW metric with vowels. Overall, the MSW metric was particularly suitable for fine-grained differentiation of phonological accuracy in MSW production.

Fricative acquisition in English- and Icelandic-speaking preschoolers with protracted phonological development.

Few studies have directly compared fricative development across languages. The current study examined voiceless fricative production in Icelandic- versus English-speaking preschoolers with protracted phonological development (PPD). Expected were: a low fricative match (with age effect), highest match levels for /f/ and non-word-initial fricatives, developmentally early mismatch (error) patterns including deletion, multiple feature category mismatches or stops, and developmentally later patterns affecting only one feature category. Crosslinguistic differences in phonetic inventories were predicted to provide different options for mismatch patterns, e.g. affricates in English, [+spread glottis] segments in Icelandic. For each language, native speakers audio-recorded and transcribed single-word speech samples for thirteen 3-year-olds and ten 4-year-olds. Predictions regarding mismatches were generally confirmed. Accuracy data were partially confirmed, /f/ having a lower match than /s/ overall for the Icelandic children. Other results reflected language or group differences. The data provide confirmation that phonological acquisition reflects crosslinguistic, language-specific and child-specific influences.

Word structures of Granada Spanish-speaking preschoolers with typical versus protracted phonological development.

BACKGROUND: Research on children's word structure development is limited. Yet, phonological intervention aims to accelerate the acquisition of both speech-sounds and word structure, such as word length, stress or shapes in CV sequences. Until normative studies and meta-analyses provide in-depth information on this topic, smaller investigations can provide initial benchmarks for clinical purposes. AIMS: To provide preliminary reference data for word structure development in a variety of Spanish with highly restricted coda use: Granada Spanish (similar to many Hispano-American varieties). To be clinically applicable, such data would need to show differences by age, developmental typicality and word structure complexity. Thus, older typically developing (TD) children were expected to show higher accuracy than younger children and those with protracted phonological development (PPD). Complex or phonologically marked forms (e.g. multisyllabic words, clusters) were expected to be late developing. METHODS & PROCEDURES: Participants were 59 children aged 3-5 years in Granada, Spain: 30 TD children, and 29 with PPD and no additional language impairments. Single words were digitally recorded by a native Spanish speaker using a 103-word list and transcribed by native Spanish speakers, with confirmation by a second transcriber team and acoustic analysis. The program Phon 1.5 provided quantitative data. OUTCOMES & RESULTS: In accordance with expectations, the TD and older age groups had better-established word structures than the younger children and those with PPD. Complexity was also relevant: more structural mismatches occurred in multisyllabic words, initial unstressed syllables and clusters. Heterosyllabic consonant sequences were more accurate than syllable-initial sequences. The most common structural mismatch pattern overall was consonant deletion, with syllable deletion most common in 3-year-olds and children with PPD. CONCLUSIONS & IMPLICATIONS: The current study provides preliminary reference data for word structure development in a Spanish variety with restricted coda use, both by age and types of word structures. Between ages 3 and 5 years, global measures (whole word match, word shape match) distinguished children with typical versus protracted phonological development. By age 4, children with typical development showed near-mastery of word structures, whereas 4- and 5-year-olds with PPD continued to show syllable deletion and cluster reduction, especially in multisyllabic words. The results underline the relevance of multisyllabic words and words with clusters in Spanish phonological assessment and the utility of word structure data for identification of protracted phonological development.

Physicians' perspectives on the uncertainties and implications of chromosomal microarray testing of children and families.

Chromosomal microarray analysis (CMA) has improved the diagnostic rate of genomic disorders in pediatric populations, but can produce uncertain and unexpected findings. This article explores clinicians' perspectives and identifies challenges in effectively interpreting results and communicating with families about CMA. Responses to an online survey were obtained from 40 clinicians who had ordered CMA. Content included practice characteristics and perceptions, and queries about a hypothetical case involving uncertain and incidental findings. Data were analyzed using nonparametric statistical tests. Clinicians' comfort levels differed significantly for explaining uncertain, abnormal, and normal CMA results, with lowest levels for uncertain results. Despite clinical guidelines recommending informed consent, many clinicians did not consider it pertinent to discuss the potential for CMA to reveal information concerning biological parentage or predisposition to late-onset disease, in a hypothetical case. Many non-genetics professionals ordering CMA did not feel equipped to interpret the results for patients, and articulated needs for education and access to genetics professionals. This exploratory study highlights key challenges in the practice of genomic medicine, and identifies needs for education, disseminated practice guidelines, and access to genetics professionals, especially when dealing with uncertain or unexpected findings.

A multi-modal approach to intervention for one adolescent's frontal lisp.

An adolescent with a persistent frontal lisp participated in a two-part 11-session intervention case study. The first phase used ultrasound imagery and acoustic, phonetic and voice education to provide information about articulatory setting (AS) and general awareness of the speech production process. The second phase used traditional articulation therapy, online visual-acoustic biofeedback and fluency strategies to target the frontal lisp directly (specifically /s/, /z/, /ʃ/ and /ʧ/). Trained listener evaluations of pre-intervention, post-phase 1 and post-phase 2 assessments showed no improvement after phase 1, but notable improvement in all treatment targets immediately after phase 2. These improvements were substantially maintained at assessment 4 months post-intervention. The outcomes suggest that direct training was more effective than the AS approach; however, the client's ability to self-monitor in phase 2, rapid acquisition of the targets and maintenance at 4 months post-intervention possibly reflected the knowledge gained in phase 1 about AS.

Speech assessment of Chinese-English bilingual children: accent versus developmental level.

The study aimed to evaluate the phonological profiles of Chinese-English bilingual children in primary grades relative to those of English monolinguals, and to compare these profiles with speech-language pathologists' (SLPs') ratings of children's speech in terms of accent or developmental level. Participants were 29 Chinese-English bilinguals and 25 English-monolingual children. Speech samples were collected using the Goldman-Fristoe Test of Articulation-2, either a Cantonese or Mandarin phonology test, and three sentences in a delayed repetition task. In addition, 10 SLPs rated each of the randomized sentences on either an accent or developmental level scale. Bilingual children with identified accents had significantly lower standard scores than monolingual children on the GFTA-2, but on the Chinese phonological assessments the same children showed age-expected speech. The differences in the bilingual children's scores on phonology tests in English vs Chinese highlight the need for phonological assessment in both languages. The SLP listener results further suggest that perceptual judgement may be a useful complement in phonological assessment of bilingual children but not a replacement for more formal testing.

Raman-induced Kerr-effect dual-comb spectroscopy.

We report on the first (to our knowledge) demonstration of nonlinear dual-frequency-comb spectroscopy. In multi-heterodyne femtosecond Raman-induced Kerr-effect spectroscopy, the Raman gain resulting from the coherent excitation of molecular vibrations by a spectrally narrow pump is imprinted onto the femtosecond laser frequency comb probe spectrum. The birefringence signal induced by the nonlinear interaction of these beams and the sample is heterodyned against a frequency comb local oscillator with a repetition frequency slightly different from that of the comb probe. Such time-domain interference provides multiplex access to the phase and amplitude Raman spectra over a broad spectral bandwidth within a short measurement time.

Are shoals of minnow Phoxinus phoxinus formed by close kin?

A molecular analysis examining the level of relatedness in shoaling minnows Phoxinus phoxinus was conducted. The results revealed that individuals from within the same shoal were not more closely related to each other than to individuals from other shoals. This led to the conclusion that Schreckstoff may be less likely to have evolved in the context of kin selection.

Motivations and perceptions of early adopters of personalized genomics: perspectives from research participants.

BACKGROUND/AIMS: To predict the potential public health impact of personal genomics, empirical research on public perceptions of these services is needed. In this study, 'early adopters' of personal genomics were surveyed to assess their motivations, perceptions and intentions. METHODS: Participants were recruited from everyone who registered to attend an enrollment event for the Coriell Personalized Medicine Collaborative, a United States-based (Camden, N.J.) research study of the utility of personalized medicine, between March 31, 2009 and April 1, 2010 (n = 369). Participants completed an Internet-based survey about their motivations, awareness of personalized medicine, perceptions of study risks and benefits, and intentions to share results with health care providers. RESULTS: Respondents were motivated to participate for their own curiosity and to find out their disease risk to improve their health. Fewer than 10% expressed deterministic perspectives about genetic risk, but 32% had misperceptions about the research study or personal genomic testing. Most respondents perceived the study to have health-related benefits. Nearly all (92%) intended to share their results with physicians, primarily to request specific medical recommendations. CONCLUSION: Early adopters of personal genomics are prospectively enthusiastic about using genomic profiling information to improve their health, in close consultation with their physicians. This suggests that early users (i.e. through direct-to-consumer companies or research) may follow up with the health care system. Further research should address whether intentions to seek care match actual behaviors.

The general public's understanding and perception of direct-to-consumer genetic test results.

BACKGROUND/AIMS: Direct-to-consumer (DTC) genetic testing allows consumers to discover their risk for common complex disorders. The extent to which consumers understand typical results provided by DTC genetic testing is currently unknown. Misunderstanding of the results could lead to negative consequences including unnecessary concern, false reassurance or unwarranted changes in screening behaviors. We conducted a study to investigate consumers' perceptions and understanding of DTC test results. METHODS: An online survey was posted on Facebook that included questions relating to 4 sample test results for risk of developing colorectal cancer, heart disease and skin cancer. Genetic counselors were used as a comparison group. RESULTS: 145 individuals from the general public and 171 genetic counselors completed the survey. A significant difference was found between the way the general public and genetic counselors interpreted the meaning of the DTC results. The general public respondents also believed that results in all 4 scenarios would be significantly more helpful than the genetic counselors did. Although the majority of general public respondents rated the results as easy to understand, they often misinterpreted them. CONCLUSIONS: These findings imply that the general public has the potential to misinterpret DTC results without appropriate assistance. Further research is needed to explore optimal methods of providing DTC test results and ways to minimize the risk of negative consequences for consumers.