Yoga and Cognitive Functions
Of late, there has been a lot of interest in understanding the human brain’s executive functions. Also called executive control or cognitive control functions, they refer to a system of mental processes that come into play when one is required to pay attention to a complex task and bring it to completion, while inhibiting automatic or habitual thought patterns and behaviours. Executive functions are also involved while handling novel, unanticipated and challenging situations for which one did not have any prior rehearsal. It takes a lot of effort or “mental stamina” so to speak, to use the executive functions of the mind; it is easier to continue with established habits than to change it. Likewise, it is easier to give in to temptations and impulsive actions than to resist them [1].
The general consensus is that there are three core components of the executive system:
1) Inhibition — which includes self-control (behavioural inhibition) and selective attention (cognitive inhibition)
2) Working memory
3) Cognitive flexibility — which is also closely connected to creativity
Inhibition: Inhibitory control involves the ability to control one’s attention, thoughts, emotions and behavior to override strong internal predispositions, old, conditioned thoughts and responses, tempting stimuli in the environment and act in a manner that is most appropriate to the situation. Inhibitory control allows one to choose the manner in which one reacts to a situation rather than becoming an impulsive creature of habit.
Self-control, an aspect of inhibitory control is to do with resisting temptations, for example, the temptation to eat a lot of fast food while trying to be healthy or going for a movie/playing video games while having to study for an exam. Self-control also involves control of emotional responses and avoiding impulsive reactions, for example, striking back at someone who said something irritating or hurtful.
The other important aspect is selective attention, which is the discipline to stay on task in spite of distractions and bring it to completion, even when one feels like giving up or moving on to more interesting or enjoyable activities. This is related to the final aspect of self-control — delayed gratification — which is basically sacrificing an immediate pleasure for a greater and long-term reward. Delayed gratification is essential to build the discipline to complete what one started, especially for long time-consuming tasks such as building a new business or organization, establishing a new medical practice, writing a scientific paper or book, training for a marathon, etc.
Working memory: Cognitive science looks at three different types of memory: long-term, short-term, and working memory. Working memory is the second core component of the executive system and involves holding information in the mind space and mentally working with it. In order to understand or contemplate any phenomenon that unfolds over time, working memory is crucial because it helps relate events in time. For example, identifying cause-effect relations, planning actions based on past information, retaining partial results while solving a math problem mentally, understanding written or spoken language by connecting ideas represented in the sentences and paragraphs, etc require an able working memory.
Cognitive flexibility: The third core component is cognitive flexibility, which builds on cognitive control and working memory and emerges later in the development process. It includes being able to change perspective or point of view, for instance, being able to imagine a scene or landscape from a different viewing direction or being able to place oneself in another person’s situation and understand their thoughts and emotions. Cognitive flexibility includes the ability to adjust to changing priorities, accept mistakes and learn from them, and utilize unexpected opportunities that arise suddenly, as is typically encountered when one starts a new business or organization. It also includes creativity and thinking “out of the box”, which is the heart of innovation and discovery of knowledge.
Higher order executive functions such as reasoning, problem solving, planning and decision making are built upon these three components. These skills are essential for almost all aspects of life, be it mental health, physical health, success in school, work, marital harmony, and social order such as prevention of crime, reckless behaviour and violence. Executive functions are impacted by psychophysical factors like stress, lack of sleep, lack of exercise, obesity, improper diet, and psychosocial factors like loneliness and drug abuse. These functions can also be trained and developed through different methods. It is also well-established that executive functions can be improved at any age, be it infancy or old age. There is a strong evidence that improving physical fitness improves executive functions in the elderly. In this article, we will look at how yogic practices impact the mind’s executive system.
In yogic thought, the emotional and cognitive processes of the mind are primarily influenced by the level of prana, the vital life energy, in the body. Yogic sciences speak of a subtle energy body, known as the pranamaya kosha, that links the mind and physical body. The mind includes the components of manomaya kosha, the indiscriminate mind involved in basic sensory and emotion processing, the vijnanamaya kosha, the higher discriminating intellect and anandamaya kosha, the innate nature of bliss and self-contentment. The development of these higher faculties of the mind require a significant shift in the quantum of prana. Among all the organs, the brain utilizes maximum prana. An insufficient supply of prana makes the mind restless and disturbed and it constantly dives into negative thoughts. As prana is externally manifested as the breath, yogis state that the level of prana is sustained and increased by deepening the inhalation and exhalation process. Yogic practices such as asana, pranayama and dhyana (meditation) generate higher levels of prana. They also create a detachment from pursuit of sensory gratification and allow the practitioner to conserve their energy for creative and spiritual development [2].
Several cognitive psychology and neuroscience studies have demonstrated the improvement of executive functions in populations following yoga and mindfulness practice. Mindfulness is a form of meditation in the Buddhist tradition. These studies make use of cognitive tests such as the Stroop task, backward digit span, creative uses task, trail making test, etc. that assess the core components such as inhibitory control, working memory and cognitive flexibility.
In a randomized control study comparing the effects of yoga and physical exercise on executive function in adolescent school children, it was found that one hour of daily yoga training for 2 months improved executive function, attention, and memory as effectively as physical exercise [3].
A review of Hatha yoga studies on executive function shows that Hatha yoga indicates benefits for executive function in healthy adults, children, adolescents, healthy older adults, prisoners, and certain medical populations [4].
In a brain imaging study on the effects of meditation practice (Sahaja Yoga Meditation) on structural and functional changes in the brain, the meditation participants, relative to control, showed a significant change in brain structure and intrinsic activity in the inferior fronto-insular regions associated with executive control relative to the control subjects. They also demonstrated a significant improvement in perceived general well-being following meditation training [5].
In yogic thought, the emotional and cognitive processes of the mind are primarily influenced by the level of prana, the vital life energy, in the body. Yogic sciences speak of a subtle energy body, known as the pranamaya kosha, that links the mind and physical body. The mind includes the components of manomaya kosha, the indiscriminate mind involved in basic sensory and emotion processing, the vijnanamaya kosha, the higher discriminating intellect and anandamaya kosha, the innate nature of bliss and self-contentment. The development of these higher faculties of the mind require a significant shift in the quantum of prana. Among all the organs, the brain utilizes maximum prana. An insufficient supply of prana makes the mind restless and disturbed and it constantly dives into negative thoughts. As prana is externally manifested as the breath, yogis state that the level of prana is sustained and increased by deepening the inhalation and exhalation process. Yogic practices such as asana, pranayama and dhyana (meditation) generate higher levels of prana. They also create a detachment from pursuit of sensory gratification and allow the practitioner to conserve their energy for creative and spiritual development [2].
Several cognitive psychology and neuroscience studies have demonstrated the improvement of executive functions in populations following yoga and mindfulness practice. Mindfulness is a form of meditation in the Buddhist tradition. These studies make use of cognitive tests such as the Stroop task, backward digit span, creative uses task, trail making test, etc. that assess the core components such as inhibitory control, working memory and cognitive flexibility.
In a randomized control study comparing the effects of yoga and physical exercise on executive function in adolescent school children, it was found that one hour of daily yoga training for 2 months improved executive function, attention, and memory as effectively as physical exercise [3].
A review of Hatha yoga studies on executive function shows that Hatha yoga indicates benefits for executive function in healthy adults, children, adolescents, healthy older adults, prisoners, and certain medical populations [4].
In a brain imaging study on the effects of meditation practice (Sahaja Yoga Meditation) on structural and functional changes in the brain, the meditation participants, relative to control, showed a significant change in brain structure and intrinsic activity in the inferior fronto-insular regions associated with executive control relative to the control subjects. They also demonstrated a significant improvement in perceived general well-being following meditation training [5].
Another fMRI study on school children found the first causal evidence that mindfulness training preserves sustained attention and associated neural plasticity [6]. The default mode network is a network of brain regions that is associated with mind-wandering and task-unrelated thoughts. The central executive network, as the name implies, is associated with executive functions. The right dorsolateral prefrontal cortex (DLPFC; shown in the figure) is a key node of the central executive network. These two networks (DMN and DLPFC) have an inverse correlation. It was found that following training, children in the mindfulness group preserved their sustained attention performance as well as the DMN-DLPFC anti-correlation when compared to the children in the active control group, who exhibited declines in both.
Executive functions are critical cognitive skills necessary for success in any endeavour that is long and requires sustained effort. They are also essential for solving many of the complex systemic problems we see today. Many successful entrepreneurs, scientists, organizational leaders and political leaders attribute their success to the time they spent in developing executive functions such as flexibility, self-control and creativity. Many such individuals pick up these skills as they tread their life path, making use of both challenges and opportunities. However, it is exciting to know that the yogic science offers clear methods by which one can overcome one’s habitual patterns of thought and behaviour and develop creative intelligence and higher order cognitive abilities with systematic practice.
REFERENCES
[1] Diamond A. Executive functions. Annu Rev Psychol 2013;64:135–68. https://doi.org/10.1146/annurev-psych-113011-143750.
[2] Saraswati SN. Prana and pranayama. Yoga Publication Trust; 2009.
[3] Vhavle SP, Rao RM, Manjunath NK. Comparison of Yoga versus Physical Exercise on Executive Function, Attention, and Working Memory in Adolescent Schoolchildren: A Randomized Controlled Trial. Int J Yoga 2019;12:172–3. https://doi.org/10.4103/ijoy.IJOY_61_18.
[4] Luu K, Hall PA. Hatha Yoga and Executive Function: A Systematic Review. J Altern Complement Med 2016;22:125–33. https://doi.org/10.1089/acm.2014.0091.
[5] Dodich A, Zollo M, Crespi C, Cappa SF, Laureiro Martinez D, Falini A, et al. Short-term Sahaja Yoga meditation training modulates brain structure and spontaneous activity in the executive control network. Brain Behav 2019;9:e01159. https://doi.org/10.1002/brb3.1159.
[6] Bauer CCC, Rozenkrantz L, Caballero C, Nieto-Castanon A, Scherer E, West MR, et al. Mindfulness training preserves sustained attention and resting state anticorrelation between default-mode network and dorsolateral prefrontal cortex: A randomized controlled trial. Hum Brain Mapp 2020;41:5356–69. https://doi.org/10.1002/hbm.25197.
