The effect of 4-weeks exposure to music on social bonding between rats.

Interpersonal synchronization of movement induced by music is believed to facilitate social bonding between human beings, but it is unknown whether it also works in animals. We allowed rats to interact and develop social bonding with a specific subject for four weeks under one of the three acoustic conditions: playback of K.448 at its original tempo, playback at its double-tempo, and silence. The strength of social bonding between each pair of rats was then measured. The results showed an increase in preference for rats that had interacted under the original tempo playback compared to the other acoustic conditions. Considering that rats move in synchrony with the beat more robustly and consistently between subjects under the original tempo playback than under the double-tempo playback, this result suggests that motor synchronization between subjects through music may facilitate social bonding between rats.

Spontaneous beat synchronization in rats: Neural dynamics and motor entrainment.

Beat perception and synchronization within 120 to 140 beats/min (BPM) are common in humans and frequently used in music composition. Why beat synchronization is uncommon in some species and the mechanism determining the optimal tempo are unclear. Here, we examined physical movements and neural activities in rats to determine their beat sensitivity. Close inspection of head movements and neural recordings revealed that rats displayed prominent beat synchronization and activities in the auditory cortex within 120 to 140 BPM. Mathematical modeling suggests that short-term adaptation underlies this beat tuning. Our results support the hypothesis that the optimal tempo for beat synchronization is determined by the time constant of neural dynamics conserved across species, rather than the species-specific time constant of physical movements. Thus, latent neural propensity for auditory motor entrainment may provide a basis for human entrainment that is much more widespread than currently thought. Further studies comparing humans and animals will offer insights into the origins of music and dancing.

Comparison of electrocardiogram quality and clinical interpretations using prepositioned ECG electrodes and conventional individual electrodes.

BACKGROUND: Efforts have been made to simplify and reduce technical errors, such as limb leads reversal and inaccurate chest leads placement, for the 12-lead ECG tests. We compared standard ECG using individual electrodes with a novel pre-positioned electrode system to determine equivalency. METHODS: Subjects were recruited from the Emergency Department and cardiac lab of an acute care hospital in Los Angeles. First, subjects underwent a conventional 12-lead ECG using Philips PageWriter (clinical ECG). A second ECG was then performed using a novel system containing pre-positioned electrodes and a compact recorder (study ECG). All ECGs were reviewed by 3 blinded, board-certified adult cardiologists using 14 pre-specified ECG diagnostic categories to determine if the interpretations of clinical ECG and study ECG of the same patient were "equivalent". Majority rule was applied when there were discrepant interpretations among the 3 cardiologists. RESULTS: One hundred subjects, ages 18 to 74 completed the study. With pre-positioned electrodes, the rate of "electrode fit" as judged by the research associates at the time of lead placement was 96.2%. We found that the study ECG system was equivalent (in clinical interpretation) to the clinical ECG system, with equivalency rate of 96% (95% confidence interval 92% to 100%) in "overall interpretation". The equivalence rate for the 14 ECG diagnostic categories ranged from 96% to 100%, with mean 99.2 ± 1.1%. CONCLUSIONS: 12-lead ECGs performed using single-piece, pre-positioned electrodes are clinically equivalent to those performed using 10 individually placed conventional electrodes. With 4 sizes for adults, the single-piece electrodes can fit 96% of the study patients.

Urban/rural residence effect on emergency department visits arising from food-induced anaphylaxis.

BACKGROUND: Anaphylaxis is a severe and potentially fatal allergic response. Early-life exposure to rural environments may help protect against allergic reaction. This study assesses urban/rural differences by age and race/ethnicity in emergency department (ED) pediatric visit rates for food-induced anaphylaxis. METHODS: This observational study examined 2009-2014 inpatient and ED data from New York and Florida, using ICD-9-CM diagnostic code (995.6) to identify food-induced anaphylaxis cases <18 y/o. Primary predictor of interest was urban/rural setting, with race/ethnicity and age also evaluated. Associations between ED visit rates and urban/rural setting were evaluated by multivariable hierarchical negative binomial regression with state and year fixed effects. RESULTS: ED visit rates (per 100,000) for food-induced anaphylaxis were 12.31 and 4.60 in urban and rural settings, respectively. Rates were highest among Blacks (15.26) younger urban children (17.29) and older rural children (6.99). Compared to rural, urban children had significantly higher anaphalaxis ED visit rates (IRR 2.77). CONCLUSIONS: Food-induced anaphylaxis ED visit rates were highest among younger urban children and Black children, with a notable contrast in age distribution between urban and rural rates. Higher urban rates may be attributed to Hygiene Hypothesis, though racial, economic and emergency care access disparities may also influence these outcomes.