Auditory mismatch negativity: detecting spectral contrasts in a modulated noise

The ability to detect sinusoidal spectral envelope from an unmodulated (flat) spectrum has shown a strong correlation with speech perception in quiet and noisy listening conditions in normal hearing, hearing-impaired, and cochlear implant users. In this study, the mismatch negativity (MMN) was collected from 10 normal-hearing adult listeners and used to determine if modulation detection thresholds derived electrophysiologically correlate with the psychophysically measured spectral modulation detection thresholds. MMNs were present for most participants with spectral contrasts of 10 and 20 dB, suggesting that the MMN may be a promising neurophysiologic measure of spectral envelope perception when nonbehavioral measures are desired.     

Effect of a Single Session of a Yogic Meditation Technique on Cognitive Performance in Medical Students: A Randomized Crossover Trial

Medical students confront enormous academic, psychosocial, and existential stress throughout their training, leading to a cascade of consequences both physically and psychologically. The declined cognitive function of these students interferes in their academic performance and excellence. The purpose of this study was to examine the effectiveness of a yogic meditation technique, mind sound resonance technique (MSRT), on cognitive functions of University Medical students in a randomized, two-way crossover study. In total, 42 healthy volunteers of both genders (5 males and 37 females) with mean age of 19.44 ± 1.31 years were recruited from a medical college in South India, based on the inclusion and exclusion criteria. A 10-day orientation in the technique of MSRT was given to all the recruited subjects after which each subject underwent both MSRT and supine rest (SR) sessions. All participants were randomized in a 1:1 ratio to receive a session of either MSRT or SR. After a day of washout, participants crossed over to receive the alternative intervention. The cognitive functions were assessed using 2 paper-pencil tasks called Digit Letter Substitution Test (DLST) and Six-Letter Cancelation Task (SLCT), before and immediately after both sessions. Both the groups showed significant improvement in net attempt of both DLST and SLCT, but the magnitude of change was more in the MSRT group than in the SR group. The MSRT group demonstrated significantly enhanced net scores in both SLCT (p < 0.001) and DLST (p < 0.001). The result of the present study suggests that a single session of MSRT, a Mind–Body Practice, may positively impact the performance in cognitive tasks by the University Medical Students.