Faculty Bibliography

The production and perception of music is preferentially mediated by cortical areas within the right hemisphere, but little is known about how these brain regions individually contribute to this process. In an experienced singer undergoing awake craniotomy, we demonstrated that direct electrical stimulation to a portion of the right posterior superior temporal gyrus (pSTG) selectively interrupted singing but not speaking. We then focally cooled this region to modulate its activity during vocalization. In contrast to similar manipulations in left hemisphere speech production regions, pSTG cooling did not elicit any changes in vocal timing or quality. However, this manipulation led to an increase in the pitch of speaking with no such change in singing. Further analysis revealed that all vocalizations exhibited a cooling-induced increase in the frequency of the first formant, raising the possibility that potential pitch offsets may have been actively avoided during singing. Our results suggest that the right pSTG plays a key role in vocal sensorimotor processing whose impact is dependent on the type of vocalization produced.

Significant technological advances have fostered a movement toward minimally invasive surgical interventions for the management of ventral skull base malignancies. The care of patients with these lesions ideally involves an interdisciplinary skull base team that includes otolaryngologists, neurologic surgeons, radiation oncologists, and medical oncologists. This overview describes considerations essential for diagnosis, prognosis, and preoperative evaluation. Furthermore, surgical nuances, strategies for skull base reconstruction, and nonsurgical options are briefly discussed. Our hope is that this overview may be useful as an up-to-date description of the challenging clinical scenarios associated with these lesions.

The sequential activation of neurons has been observed in various areas of the brain, but in no case is the underlying network structure well understood. Here we examined the circuit anatomy of zebra finch HVC, a cortical region that generates sequences underlying the temporal progression of the song. We combined serial block-face electron microscopy with light microscopy to determine the cell types targeted by HVC_(RA)neurons, which control song timing. Close to their soma, axons almost exclusively targeted inhibitory interneurons, consistent with what had been found with electrical recordings from pairs of cells. Conversely, far from the soma the targets were mostly other excitatory neurons, about half of these being other HVC_(RA)cells. Both observations are consistent with the notion that the neural sequences that pace the song are generated by global synaptic chains in HVC embedded within local inhibitory networks.

Importance/UNASSIGNED:The number of patients using the internet to obtain health information is growing. This material is unregulated and heterogeneous and can influence patient decisions. Objective/UNASSIGNED:To compare the quality, readability, and technical aspects of online information about neck-lifts provided by private practice websites vs academic medical centers and reference sources. Design, Setting, and Participants/UNASSIGNED:In this cross-sectional analysis conducted between November 2015 and January 2016, a Google search of the term neck-lift was performed, and the first 45 websites were evaluated. The websites were categorized as private practice vs other. Private websites (PWs) included sites created by private practice physicians. Other websites (OWs) were created by academic medical centers or reference sources. Main Outcomes and Measures/UNASSIGNED:Quality, readability, and technical aspects of online websites related to neck-lifts. Quality was assessed using the DISCERN criteria and the Health on the Net principles (HONcode). Readability was assessed using 7 validated and widely used criteria. Consensus US reading grade level readability was provided by a website (readabilityformulas.com). Twelve technical aspects were evaluated based on criteria specified by medical website creators. Results/UNASSIGNED:Forty-five websites (8 OWs [18%] and 37 PWs [82%]) were analyzed. There was a significant difference in quality between OWs and PWs based on the DISCERN criteria and HONcode principles. The DISCERN overall mean (SD) scores were 2.3 (0.5) for OWs and 1.3 (0.3) for PWs (P < .001). Of a total possible score of 14 using the HONcode analysis, the mean (SD) was 8.6 (1.8) (range, 5-11) for OW, and the mean (SD) was 5.8 (1.7) (range, 2-9) for PW. The mean (SD) readability consensus reading grade level scores were 11.7 (1.9) for OWs and 10.6 (1.9) for PWs. Of a total possible score of 12, the mean (SD) technical scores were 6.3 (1.8) (range, 4-9) for OWs and 6.4 (1.5) (range, 3-9) for PWs. Conclusions and Relevance/UNASSIGNED:Compared with PWs, OWs had a significantly higher quality score based on both the DISCERN criteria and HONcode principles. The mean readability for OWs and PWs was grade 11 and grade 10, respectively, significantly higher than the grade 7 level recommended by the National Institutes of Health. Assessment of technical criteria demonstrated room for improvement in providing links to social media and blogs and reducing advertisements. Improving the quality and readability of online information may result in increased patient understanding, more active patient involvement, and ultimately better outcomes. Enhancing the technical aspects of websites may increase website traffic and patient volume. Level of Evidence/UNASSIGNED:NA.

BACKGROUND: Cochlear implants (CIs) successfully restore hearing in postlingually deaf adults, but in doing so impose a frequency-position function in the cochlea that may differ from the physiological one. PURPOSE: The CI-imposed frequency-position function is determined by the frequency allocation table programmed into the listener's speech processor and by the location of the electrode array along the cochlea. To what extent can postlingually deaf CI users successfully adapt to the difference between physiological and CI-imposed frequency-position functions? RESEARCH DESIGN: We attempt to answer the question by combining behavioral measures of electroacoustic pitch matching (PM) and measures of electrode location within the cochlea. STUDY SAMPLE: The participants in this study were 16 adult CI users with residual hearing who could match the pitch of acoustic pure tones presented to their unimplanted ears to the pitch resulting from stimulation of different CI electrodes. DATA COLLECTION AND ANALYSIS: We obtained data for four to eight apical electrodes from 16 participants with CIs (most of whom were long-term users), and estimated electrode insertion angle for 12 of these participants. PM functions in this group were compared with the two frequency-position functions discussed above. RESULTS: Taken together, the findings were consistent with the possibility that adaptation to the frequency-position function imposed by CIs does happen, but it is not always complete. CONCLUSIONS: Some electrodes continue to be perceived as higher pitched than the acoustic frequencies with which they are associated despite years of listening experience after cochlear implantation.

Pleomorphic xanthoastrocytoma (PXA) is a World Health Organization (WHO) Grade II glioma occurring primarily in children and young adults. Most PXAs harbor the known activating mutation BRAF V600E. We report a case of locally recurrent PXA with anaplastic features in a 10-yr-old female. The PXA was negative by immunohistochemical (IHC) staining for BRAF V600E mutation. Whole-exome and transcriptome sequencing of the tumor confirmed the absence of BRAF V600E, but identified copy-number alterations (including loss of the tumor suppressor CDKN2A) and a novel TMEM106B-BRAF fusion. Based on similar BRAF fusion proteins, this novel fusion is predicted to result in activation of BRAF signaling. Demonstration of positive IHC for phospho-ERK1/2 and phospho-MEK1/2 supported this prediction, and implicated MEK inhibitors as a potential therapeutic strategy.

Epileptogenic tumors affecting children and young adults are a morphologically diverse collection of neuroepithelial neoplasms that, as a group, exhibit varying levels of glial and/or neuronal differentiation. Recent advances in molecular profiling technology, including comprehensive DNA sequencing and methylation analysis, have enabled the application of more precise and biologically relevant classification schemes to these tumors. In this report, we describe a morphologically and molecularly distinct epileptogenic neoplasm, the polymorphous low-grade neuroepithelial tumor of the young (PLNTY), which likely accounts for a sizable portion of oligodendroglioma-like tumors affecting the pediatric population. Characteristic microscopic findings most notably include infiltrative growth, the invariable presence of oligodendroglioma-like cellular components, and intense immunolabeling for cluster of differentiation 34 (CD34). Moreover, integrative molecular profiling reveals a distinct DNA methylation signature for PLNTYs, along with frequent genetic abnormalities involving either B-Raf proto-oncogene (BRAF) or fibroblast growth factor receptors 2 and 3 (FGFR2, FGFR3). These findings suggest that PLNTY represents a distinct biological entity within the larger spectrum of pediatric, low-grade neuroepithelial tumors.