ALTERATIONS IN AUDITORY MIDDLE LATENCY EVOKED POTENTIALS DURING MEDITATION ON A MEANINGFUL SYMBOL - OM 
Abstract: Middle latency auditory evoked potentials were recorded in 18 male volunteers with ages between 25 and 45 years, 9 of whom had more than ten years of experience in OM meditation (senior subjects), whereas the other 9 had no meditation experience (naive subjects). Both groups were studied in two types of sessions. (1) Before, during, and after 20 minutes of mentally repeating "one" (control session), and (2) a similar session, though with 20 minutes of mentally chanting OM (meditation session). The senior subjects showed a statistically significant (paired t-test) increase in the peak amplitude of Na wave (the maximum negative peak between 14 and 18 ms) during meditation, while the same subjects showed a statistically significant reduction in the Na wave peak amplitude during control sessions. In contrast, the naive subjects had a significant decrease in the Na wave peak amplitude during meditation sessions and a nonsignificant trend of reduction during control sessions, as well. This difference between senior and naive subjects was significant (two way ANOVA). There were no significant changes in short latency wave V or Pa wave (the positive peak between the Na wave and 35 ms). The changes in the Na wave suggest that both meditation on a meaningful symbol, and mental repetition of a neutral word cause neural changes at the same level (possibly diencephalic). However, the change could be in opposite directions, and this difference could be correlated with differences in the duration of experience in meditation between senior and naive subjects. Read More...

RECORDING OF AUDITORY MIDDLE LATENCY EVOKED POTENTIALS DURING THE PRACTICE OF MEDITATION WITH THE SYLLABLE "OM"
Abstract: Middle latency auditory evoked potentials were examined in 7 proficient subjects during the practice of meditation on the syllable "Om", to determine whether these potentials would differ significantly from those recorded during the baseline state without practicing meditation. Similar records were also obtained in 7 "naive" subjects, matched for age, before and during a control period which involved sitting with eyes closed, and with no special instructions for focusing their thoughts. There was considerable inter-subject variability in the different components. However, during meditation there was a small but significant reduction in the peak latency of the Nb wave (the maximum negativity occurring between 35 and 65 msec). This reduction was observed consistently during the 3 repeat sessions of each subject, while the "naive" subjects did not show this change. These results suggest that the inter-subject variability of middle latency auditory evoked potentials precludes using them as the method of choice for assessing the effects of meditation. The small but consistent decrease in the Nb wave peak latency, indicates that the middle latency auditory evoked potentials do change with meditation. However, the variability of the potentials may mask subtle changes. Read More...

SHORT COMMUNICATION AUTONOMIC CHANGES DURING "OM" MEDITATION 
Abstract: The autonomic and respiratory variables were studied in seven experienced meditators (with experience ranging from 5 to 20 years). Each subject was studied in two types of sessions - meditation (with a period of mental chanting of "OM") and control (with a period of non-targetted thinking). The meditators showed a statistically significant reduction in heart rate during meditation compared to the control period (paired "t" test). During both types of sessions there was a comparable increase in the cutaneous peripheral vascular resistance. Keeping in mind similar resulta of other authors, this was interpreted as a sign of increased mental alertness, even while being physiologically relaxed (as shown by the reduced heart rate). Read More...

HEART RATE AND RESPIRATORY CHANGES ACCOMPANYING YOGIC CONDITIONS OF SINGLE THOUGHT AND THOUGHTLESS STATES
It has been established (1, 2) that certain yogis can alter the patterns of their cardiovascular functions voluntarily. This report presents information obtained in a subject who practised yoga of thoughtless state for many years. The heart rate and respiratory changes associated with states of thought control have been recorded. Informed consent was obtained from the subject for the study. YS was a 76 year old healthy and active male, at the time of the study. Read More...

AUTONOMIC CHANGES WHILE MENTALLY REPEATING TWO SYLLABLES - ONE MEANINGFUL AND THE OTHER NEUTRAL
Abstract: Autonomic and respiratory variables were recorded in 12 volunteers in three types of sessions (1) Before, during and after a test period of mentally repeating a meaningful syllable "OM" (MOM session) ,(2) A similar session except that the test period was spent mentally repeating a neutral word "one" (COM session), (3) A session with non-targeted thinking (NT session). The subjects were familiar with both syllables, and had been meditating on "OM" for 20 days. During the test periods of both MOM and COM sessions the rate of respiration (RR) and heart rate (HR) decreased significantly [two factor ANOVA (RR), paired t test (RR. HR)],compared to the pre period, mental repetition of "OM" (but not "one") caused a significant decrease in skin resistance level (SRL) (paired t test). This was taken to mean that the subject recognized the significance of the syllable. No significant change occurred during NT sessions.  Read More...

AUTONOMIC CHANGES IN BRAHMAKUMARIS RAJA YOGA MEDITATION
Abstract: This report presents the changes in various autonomic and respiratory variables during the practice of Brahmakumaris Raja yoga meditation. This practice requires considerable commitment and involves concentrated thinking. 18 males in the age range of 20 to 52 years (mean 34.1 ± 8.1), with 5-25 years experience in meditation (mean 10.1± 6.2), participated in the study. Each subject was assessed in three test sessions which included a period of meditation, and also in three control (non-meditation) sessions, which included a period of random thinking. Group analysis showed that the heart rate during the meditation period was increased compared to the preceding baseline period, as well as compared to the value during the non-meditation period of control sessions. In contrast to the change in the heart rate, there was no significant change during meditation, for the group as a whole, in palmar GSR, finger plethysmogram amplitude, and respiratory rate. On an individual basis, changes which met the following criteria were noted: (1) changes which were greater during meditation (compared to its preceding baseline) than changes during post meditation or non- meditation periods (also compared to their preceding baseline); (2) Changes which occurred consistently during the three repeat sessions of a subject and (3) changes which exceeded arbitrarilychosen cut- off points (described at length below). This individual level analysis revealed that changes in autonomic variables suggestive of both activation and relaxation occurred simultaneously in different subdivisions of the autonomic nervous system in a subject. Apart from this, there were differences in patterns of change among the subjects who practised the same meditation. Hence, a single model of sympathetic activation or overall relaxation may be inadequate to describe the physiological effects of a meditation technique. Read More...

YOGA BASED GUIDED RELAXATION REDUCES SYMPATHETIC ACTIVITY IN SUBJECTS BASED ON BASELINE LEVELS
Summary: 35 male volunteers with ages ranged from 20 to 46 yrs were studied in two sessions, of yoga based guided relaxation and supine rest. Assessments of autonomic parameters were made in 15 subjects, before, during and after the practices, whereas oxygen consumption and breath volume were recorded in 25 subjects, before and after both types of relaxation. A significant decrease in oxygen consumption and increase in breath volume were recorded after guided relaxation (paired t test). There were comparable reductions in heart rate and skin conductance level during both types of relaxation. During guided relaxation the power of the low frequency component of the heart rate variability spectrum reduced, whereas the power of the high frequency component increased, suggesting reduced sympathetic activity. Also subjects with a base line ratio of LF/HF >0.5 showed a significant decrease in the ratio after guided relaxation, while subjects with a ratio < 0.5 at baseline showed no such change. The results suggest that sympathetic activity decreased after guided relaxation based on yoga, depending on the base line levels Read More...

OXYGEN CONSUMPTION AND RESPIRATION FOLLOWING TWO YOGA RELAXATION TECHNIQUES
The present study was conducted to evaluate a statement in ancient yoga texts which suggests that a combination of both "calming" and "stimulating" measures may be especially helpful in reaching a state of mental equilibrium. Two yoga practices, one combining "calming and stimulating" measures (cyclic meditation) and the other, a "calming" technique (shavasan), were compared. The oxygen consumption, breath rate and breath volume, of 40 male volunteers (group mean ± SD, 27.0 ± 5.7 Years) were assessed before and after sessions of cyclic meditation (CM) and before and after sessions of shavasan (SH). The two sessions (CM, SH) were one day apart. Cyclic meditation includes the practice of yoga postures interspersed with periods of supine relaxation. During SH the subject lies in a supine position throughout the practice. There was a significant decrease in the amount of oxygen consumed and in breath rate and an increase in breath volume after both types of sessions (two factor ANOVA, paired t test). However, magnitude of change on all three measures was greater after cyclic meditation. (i) Oxygen consumption decreased 32.1 % after CM compared with 10.1% after SH; (ii) breath rate decreased 18.0% after CM and 15.2% after SH; and (iii) breath volume increased 28.8% after CM and 15.9% after SH. These results support the idea that a combination of yoga postures interspersed with relaxation reduces arousal more than relaxation alone does. Read More...

YOGA BASED ISOMETRIC RELAXATION VERSUS SUPINE REST: A STUDY OF OXYGEN CONSUMPTION, BREATH RATE AND VOLUME AND AUTONOMIC MEASURES R.P.
Forty male volunteers with ages ranging from 16 to 46 yrs ware studied in two sessions, yoga based isometric relaxation technique (IRT) and supine rest (SR). Assessments of autonomic parameters were made in 15 subjects, before and after the practices, whereas oxygen consumption, breath rate and breath volume were recorded in 25 subjects, before and after IRT and SR. A significant decrease in breath rate after IRT and in linger Plethysmogram was recorded after SR. The results suggest possibilities for IRT in reducing some physiological signs of anxiety. Read More...