ABSTRACT
Abstract Introduction The spatial auditory system, though developed at birth, attains functional maturity in the late childhood (12 years). Spatial changes during childhood affect navigation in the environment and source segregation. Accommodation of a new skill through learning, especially during childhood, can expedite this process. Objective To explore the auditory spatial benefits of abacus training on psychoacoustic metrics in children. The study also aimed to identify the most sensitive metric to abacus training related changes in spatial processing, and utilize this metric for a detailed spatial error profiling. Methods A standard group comparison analysis with 90 participants divided into three groups: I: children with abacus training (C-AT); II: children with no training (C-UT); III: adults with no training (A-UT). The groups underwent a series of psychoacoustic tests, such as interaural time difference (ITD), interaural level difference (ILD), and virtual auditory space identification (VASI), as well as perceptual tests such as the Kannada version of the speech, spatial, and quality questionnaire (K-SSQ). Results Significant group differences were observed in the multivariate analysis of variance (MANOVA) and post-hoc tests, with the C-AT group showing significantly lower ILD scores (p = 0.01) and significantly higher VASI scores (p < 0.001) compared to the CUT group, which is indicative of better spatial processing abilities in the former group. The discriminant function (DF) analyses showed that the VASI was the most sensitive metric for training-related changes, based on which elaborate error analyses were performed. Conclusions Despite the physiological limits of the immature neural framework, the performance of the C-AT group was equivalent to that of untrained adults on psychoacoustic tests, which is reflective of the positive role of abacus training in expediting auditory spatial maturation.
ABSTRACT
Bottled water is generally accepted as safe for consumption. However, its potability is uncertain. Ninety samples of Six national and 3 local brands marketed in Mangalore City were studied. Seven of these were ISI certified. Bacteriological analysis of these samples were carried out for viable count, presumtive coliform count by multiple tube method, confirmed Esch. coli count by Eijkman test and specific intestinal pathogens, such as Salmonella, Shigella and Vibrios. Thirty out of 90 samples though free from coliforms, had viable count much higher than specified by Bureau of Indian Standard. Three samples of one of the brands which is ISI not certified had Esch. coli with most probable number 18/100 ml and Salmonella typhimurium. It is concluded that bottled water can not be taken for granted to be safe.