Spatiospectral brain networks reflective of improvisational experience.

Musical improvisers are trained to categorize certain musical structures into functional classes, which is thought to facilitate improvisation. Using a novel auditory oddball paradigm (Goldman et al., 2020) which enables us to disassociate a deviant (i.e. musical chord inversion) from a consistent functional class, we recorded scalp EEG from a group of musicians who spanned a range of improvisational and classically trained experience. Using a spatiospectral based inter and intra network connectivity analysis, we found that improvisers showed a variety of differences in connectivity within and between large-scale cortical networks compared to classically trained musicians, as a function of deviant type. Inter-network connectivity in the alpha band, for a time window leading up to the behavioural response, was strongly linked to improvisation experience, with the default mode network acting as a hub. Spatiospectral networks post response were substantially different between improvisers and classically trained musicians, with greater inter-network connectivity (specific to the alpha and beta bands) seen in improvisers whereas those with more classical training had largely reduced inter-network activity (mostly in the gamma band). More generally, we interpret our findings in the context of network-level correlates of expectation violation as a function of subject expertise, and we discuss how these may generalize to other and more ecologically valid scenarios.

Chlorthalidone: the forgotten diuretic.

Chlorthalidone's safety and efficacy in the management of hypertension has been demonstrated in landmark trials. Despite understanding the effects of thiazides on urinary sodium excretion and intravascular volume, the exact mechanism of their antihypertensive effects is not clearly understood. Common compensatory mechanisms for decreases in circulating plasma volume include increased adrenergic tone and systemic vascular resistance, as well as increases in the renin-angiotensin-aldosterone system. Chlorthalidone has been shown to decrease platelet aggregation and vascular permeability and promote angiogenesis in vitro, which is thought to be, in part, the result of reductions in carbonic anhydrase-dependent pathways, including catecholamine-mediated platelet aggregation and downregulation of VEGF-C gene expression. This article reviews the comparative clinical data between chlorthalidone and hydrochlorothiazide, the pharmacologic properties that might explain some of their differences regarding half-life and efficacy, and what is known about the effect of chlorthalidone on intermediate endpoints.

Blind or deaf? A matter of aesthetics.

Blind or deaf? Surprisingly, a small but noticeable minority, 17%, opted for blindness. Another 6% were indifferent. For these individuals (23% of the sample), the loss of the aesthetic experience--music--was given relatively greater weight than the loss of the practical--conversation. This was not a symmetric effect in that those who opted for being deaf did not place greater value on the aesthetic aspects of vision compared to those who opted for being blind. What predicts the preference for being blind was not the amount of time spent listening to music but the extent to which one formally studied, created, and played music and experienced intense emotions when engaged by music.

Clinical assessment of pediatric obstructive sleep apnea.

OBJECTIVE: To determine whether children with a clinical assessment suggestive of obstructive sleep apnea (OSA) but with negative polysomnography (PSG) have improvement in their clinical assessment score after tonsillectomy and adenoidectomy (T&A) as compared with similar children who do not undergo surgery. METHODS: In a prospective, randomized, investigator-blinded, controlled trial, 59 otherwise healthy children (mean age: 6.3 years [3.0]; 31 boys, 28 girls) with a clinical diagnosis of OSA (clinical assessment score 40) were recruited from the pediatric otolaryngology and pediatric pulmonary private offices and clinics of a tertiary care, academic medical center. A standardized assessment was performed on all patients, including history, physical examination, voice recording, tape recording of breathing during sleep, lateral neck radiograph, echocardiogram, and PSG. A clinical assessment score was assigned. Children with positive PSG (n = 27) were scheduled for T&A, whereas children with negative PSG (n = 29) were randomized to T&A (n = 15) or no surgery (n = 14). Children were reassessed in an identical manner at a planned 6-month follow-up. RESULTS: Follow-up was available for 21 patients with positive PSG, 11 patients with negative PSG randomized to T&A, and 9 nonsurgery patients. In the randomized subjects, the median reduction in clinical assessment score was 49 (range: 32-61) for the T&A patients as compared with 8 (range: -9 to 29) for the nonsurgery patients. Nine (82%) of the T&A patients were asymptomatic (clinical assessment score <20) compared with 2 (22%) of the nonsurgery patients. CONCLUSION: Children with a positive clinical assessment of OSA but negative PSG have significant improvement after T&A as compared with observation alone, thus validating the clinician's role in diagnosing upper airway obstruction.