CHANGES IN PERCEPTION FOLLOWING YOGA PRACTICEWritten by Manoj Dash,BHMS,DYT,Ph.D.
Perception is sensation with added complexity due to factors such as memories and emotions. Yoga practice influences perception in three ways: (1) by increasing perceptual sensitivity, (2) by selectively `shutting out’ undesirable stimuli, and (3) by changing distorted perception, which occurs in schizophrenia. Practicing yoga improved auditory and visual perception, by increasing sensitivity to various characteristics of stimuli (e.g., intensity, frequency). Also, electrophysiological studies using evoked potentials have shown that during yoga practice transmission of sensory information is facilitated. These studies suggest several applications of yoga practice, in activities ranging from aviation to art. Interestingly, other studies suggest that yoga practice can also help to `shut off’ undesirable external stimuli, which is possibly due to cortical feedback connections to sensory pathway. It is also possible that through changes in cognitive factors yoga influences perception, so that even though stimulus is `sensed’ it is not disturbing. This concept has been studied using yoga to help persons with chronic pain to willfully ignore it. Finally, preliminary studies have shown that yoga practice may modify distorted perception in conditions such as schizophrenia. Hence, there is sufficient research to support idea that yoga practice influences perception in different ways, with varied applications. Perception is process of interpretation, organization, and elaborating `raw materials’ of sensation (1). Sensation involves sensory receptors and pathways, whereas perception is a cognitive process. The actual perception of a sensation depends on factors such as what has been learned, memories, and emotions. It is also important to remember that while perception usually refers to sensory stimuli, this definition can be extended to include perception of situations. Recordings of middle latency auditory evoked potentials (AEP-MLRs) have shown that practice of ujjayi pranayama modifies AEP-MLRs components in two ways. A specific component (the Na wave) has reduced latency and increased amplitude during pranayama practice (2). These results suggest that this practice facilitates processing of auditory information at mesencephalic and diencephalic levels. A similar result was also seen during practice of meditation on syllable Om (3), where subjects who had more than ten years of meditation experience, showed an increase in Na wave amplitude and a decrease in its’ latency while mentally repeating (Om). No such effect was seen when same subjects mentally repeated `one’, during a control session, for comparison. These electrophysiological data are corroborated by neuropsychological studies. Previous studies on meditation have shown significant changes in perception, attention and cognition (4). Brown and Engler in 1980 (5), reported that meditators were found to be more sensitive to subtle aspects of color and shading of Rorschach test inkblots, than they had been before meditation. Two studies on Critical Flicker Fusion Frequency have shown that perceptual sensitivity is not restricted to subtle aspects of stimulus alone, as detection of a high frequency flickering stimulus was found to improve following yoga training (6,7). A study on degree of a visual geometric illusion, based on Müller-Lyer lines showed that a combination of focusing and defocusing yoga visual exercises reduces optical illusion more than focusing alone (8). These studies were conducted on adult subjects with varying durations of yoga training. It was reported in a recent study on Critical Flicker Fusion Frequency and optical illusion on children who practiced yoga for a shorter duration of 10 days that there was also a significant improvement following practice of yoga (9). To perceive an optical illusion with minimal error and for accurate depth perception spatial component of visual perception is necessary (10). The decrease in degree of optical illusion perceived over a short period would be mainly due to cognitive judgmental factors, but not retinal or cortical factors as generally understood (11). The cognitive judgmental factors involve way in which subject interprets incoming visual information based on experience, hypothesis and strategies of judgment. Hence training through yoga to focus and defocus might have influenced cognitive judgmental factors of subjects, to significantly reduce degree of optical illusion perceived. Critical flicker fusion frequency (CFF), on other hand, assesses temporal component of perception of a visual stimulus (12). The increase in CFF following yoga could be attributed to effects of yoga reducing physiological signs of stress, as CFF was found to be lower during specific stressors, such as food and water deprivation (13). This showed that both spatial and temporal components of visual perception are modified following yoga practices.
| | 9 Ways to Nurture Your Emotional HealthWritten by Brian B. Carter, MS, LAc
I think we need to break Chinese medicine's wisdom down into bite-sized, practical pieces. Though I think they are rather cliché and simplistic, popular magazine style, "5 Tips to Make Your Life Perfect in 5 Minutes Without Lifting a Finger!" piques curiosity, and gets in our heads. If we can pick up one useful thing, we've learned and can live better. On other hand, it does no good to overwhelm people with something they can't digest or use. Nine Ways to Nurture Your Emotional Well Being This list is based on Chinese medicine advice for emotions through centuries. The how-to's and benefits are mostly my ideas. The daily blueprint comes from book, "The Power of Focus". You can find other self-examination and spiritual tools in a wide range of books. 1. Be Grateful: Recognize what you've achieved, and enjoy it. Once you've reached a goal, celebrate. Otherwise you get stuck in 'never enough' trap. How: Make a weekly list of things in your life for which you are grateful. Review both new and perpetual reasons for gratitude. Benefit: You can't be grateful and hateful at same time, so more grateful you are, happier you'll be. 2. Choose Achievable Goals: Avoid overly ambitious goals, because foiled plans lead to frustration, with-drawal, and depression. How: Review your plans and dreams, and then break them down into subtasks you can definitely finish (this is called a critical path). Set realistic dates for each task. If you run into an impasse, then reassess your path, or your goal. Benefit: You'll achieve more, and feel more capable and successful. 3. Live Moderately: Work and live moderately. Balance means not overworking and not being lazy. How: Make a blueprint for each day that allocates specific times for action, learning, exercise, review, relaxation, and family. See book, The Power of Focus. Benefit: Stay well and avoid diseases that come from overwork. Feel fulfilled and avoid guilt, which drains your energy. Sharpen your saw. Improve your effectiveness and understanding. Feel satis-fied you're available to loved ones. 4. Be Regular: Keep a consistent routine in work, meals, exercise, and rest. Regularity is easier on your nervous system, so your body will know what to expect. How: Use daily blueprint tool from #3. Benefit: You experience less stress and have more vitality. 5. Eat and Sleep Sensibly: Quality sleep and a normal appetite are best signs of health, and everything else depends on them. If you want to get or stay well, take care of these two aspects of your health. How: See healthful eating tips in chapter 33 and sleep tips in chapter 56. Benefit: Natural, deep sleep renews and refreshes your mind and heals your body. Proper eating and digestion optimize your immune system and prev-ent sickness.
|
