Awake
Encyclopedia
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
state and state of consciousness in which an individual is conscious and engages in a coherent cognitive and behavior responses to the external world such as communication
Communication
Communication is the activity of conveying meaningful information. Communication requires a sender, a message, and an intended recipient, although the receiver need not be present or aware of the sender's intent to communicate at the time of communication; thus communication can occur across vast...
, ambulation, nutritional ingestion
Ingestion
Ingestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in the substance through the mouth into the gastrointestinal tract, such as through eating or drinking...
and procreation. Being awake is the opposite of the state of being asleep
Sleep
Sleep is a naturally recurring state characterized by reduced or absent consciousness, relatively suspended sensory activity, and inactivity of nearly all voluntary muscles. It is distinguished from quiet wakefulness by a decreased ability to react to stimuli, and is more easily reversible than...
in which most external inputs to the brain are excluded from neural processing.
Effects upon the brain
The longer the brain has been awake, the greater the spontaneous firing rates of cerebral cortexCerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
neurons with this increase being reversed by sleep. Another effect of wakefulness (which may or may not be related to this) is that it lowers the small stores of glycogen
Glycogen
Glycogen is a molecule that serves as the secondary long-term energy storage in animal and fungal cells, with the primary energy stores being held in adipose tissue...
held in the astrocyte
Astrocyte
Astrocytes , also known collectively as astroglia, are characteristic star-shaped glial cells in the brain and spinal cord...
s that can supply energy to the brain's neurons—one of the functions of sleep it has been proposed is to create the opportunity for them to be replenished.
Maintenance by the brain
The posterior hypothalamusHypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...
plays a key role in the maintenance of the cortical activation that underlies wakefulness. Several systems originating in this part of the brain control the shift from wakefulness into sleep and sleep into wakefulness. Histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
neurons in the tuberomamillary nucleus and nearby adjacent posterior hypothalamus project to the entire brain and are the most wake-selective system so far identified in the brain. Another key system is that provided by the orexins (also known as hypocretins) projecting neurons. These exist in areas adjacent to histamine neurons and like them project widely to most brain areas and associate with arousal. Orexin deficiency has been identified as responsible for narcolepsy
Narcolepsy
Narcolepsy is a chronic sleep disorder, or dyssomnia, characterized by excessive sleepiness and sleep attacks at inappropriate times, such as while at work. People with narcolepsy often experience disturbed nocturnal sleep and an abnormal daytime sleep pattern, which often is confused with insomnia...
.
Research suggests that orexin and histamine neurons play distinct, but complementary roles in controlling wakefulness with orexin being more involved with wakeful behavior and histamine cognition and activation of cortical EEG
EEG
EEG commonly refers to electroencephalography, a measurement of the electrical activity of the brain.EEG may also refer to:* Emperor Entertainment Group, a Hong Kong-based entertainment company...
.
It has been suggested the fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
is not awake with wakeness occurring in the newborn due to the stress of being born
Childbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
and the associated activation of the locus coeruleus.
As a state of awareness
Wakefulness is described by the American physician and meditation teacher Jon Kabat-ZinnJon Kabat-Zinn
Jon Kabat-Zinn is Professor of Medicine Emeritus and founding director of the Stress Reduction Clinic and the Center for Mindfulness in Medicine, Health Care, and Society at the University of Massachusetts Medical School. Kabat-Zinn was a student of Zen Master Seung Sahn and a founding member of...
as a state of mindful awareness or mindfulness
Mindfulness (psychology)
Modern clinical psychology and psychiatry since the 1970s have developed a number of therapeutic applications based on the concept of mindfulness in Buddhist meditation.-Definitions:...
. By being fully awake in the present moment, Kabat-Zinn suggests that we can live more fully and with greater awareness and intent, which has the potential to give us an improved sense of peace, contentment and well-being. For lying down meditation practices (as opposed to sitting
Meditation
Meditation is any form of a family of practices in which practitioners train their minds or self-induce a mode of consciousness to realize some benefit....
or walking meditation
Kinhin
In Zen Buddhism, kinhin , or , is the walking meditation that is practiced between long periods of the sitting meditation known as zazen.Practitioners walk clockwise around a room while holding their hands in shashu , with one hand closed in a fist, while the other hand grasps or covers the fist...
practices), Kabat-Zinn suggests that it may be helpful to begin by first splashing cold water on your face so that you are less likely to fall asleep. Instead, Kabat-Zinn describes the benefit of meditation as "falling awake." By being able to "fall awake," we learn to be more aware in the present moment no matter what else is happening.
Awakefulness has a special meaning within oriental schools of thought and associated esoteric teachings. These include the idea of antroposophy in which four modes of awareness are distinguished: wakefulness (conferring with dhyana
Dhyāna in Buddhism
Dhyāna in Sanskrit or jhāna in Pāli can refer to either meditation or meditative states. Equivalent terms are "Chán" in modern Chinese, "Zen" in Japanese, "Seon" in Korean, "Thien" in Vietnamese, and "Samten" in Tibetan....
), dream
Dream
Dreams are successions of images, ideas, emotions, and sensations that occur involuntarily in the mind during certain stages of sleep. The content and purpose of dreams are not definitively understood, though they have been a topic of scientific speculation, philosophical intrigue and religious...
(conferring with dharani
Dharani
A ' is a type of ritual speech similar to a mantra. The terms dharani and satheesh may be seen as synonyms, although they are normally used in distinct contexts....
), sleep (conferring with pratyahara
Pratyahara
Pratyahara or the 'withdrawal of the senses' is the fifth element among the Eight stages of Patanjali's Ashtanga Yoga, as mentioned in his classical work, Yoga Sutras of Patanjali composed in the 2nd century BCE....
) and moment of death
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....
or absorption of spirit
Spirit
The English word spirit has many differing meanings and connotations, most of them relating to a non-corporeal substance contrasted with the material body.The spirit of a living thing usually refers to or explains its consciousness.The notions of a person's "spirit" and "soul" often also overlap,...
(conferring with samādhi
Samadhi
Samadhi in Hinduism, Buddhism,Jainism, Sikhism and yogic schools is a higher level of concentrated meditation, or dhyāna. In the yoga tradition, it is the eighth and final limb identified in the Yoga Sūtras of Patañjali....
). Each of these modes of awareness (citta
Citta
Citta was one of the chief lay disciples of the Buddha. He was a wealthy merchant from Savatthi. His life and character were so pure that near his death, had he wished to be a chakravartin, it would've been granted. However, he turned down this wish as it was temporal...
) may be exercised (i.e. Yoga
Yoga
Yoga is a physical, mental, and spiritual discipline, originating in ancient India. The goal of yoga, or of the person practicing yoga, is the attainment of a state of perfect spiritual insight and tranquility while meditating on Supersoul...
) in order to enhance wisdom
Wisdom
Wisdom is a deep understanding and realization of people, things, events or situations, resulting in the ability to apply perceptions, judgements and actions in keeping with this understanding. It often requires control of one's emotional reactions so that universal principles, reason and...
(prajna
Prajña
Prajñā or paññā is wisdom, understanding, discernment or cognitive acuity. Such wisdom is understood to exist in the universal flux of being and can be intuitively experienced through meditation...
) and enlightenment
Enlightenment in Buddhism
The English term enlightenment has commonly been used in the western world to translate several Sanskrit, Pali, Chinese and Japanese terms and concepts, especially bodhi, prajna, kensho, satori and buddhahood.-Insight:...
(buddhi
Buddhi
Buddhi is a feminine Sanskrit noun derived from the same root as the more familiar masculine form Buddha Buddhi is a feminine Sanskrit noun derived from the same root as the more familiar masculine form Buddha Buddhi is a feminine Sanskrit noun derived from the same root as the more familiar...
). In Yoga these four modes of awareness, mental energies, are united with corresponding life forces (prana
Prana
Prana is the Sanskrit word for "vital life" .It is one of the five organs of vitality or sensation, viz. prana "breath", vac "speech", chakshus "sight", shrotra "hearing", and manas "thought" Prana is the Sanskrit word for "vital life" (from the root "to fill", cognate to Latin plenus...
s.) The mental states of wakefulness, Dhyanas, are corresponding to the Asana
Asana
Asana is a body position, typically associated with the practice of Yoga, originally identified as a mastery of sitting still, with the spine as a conduit of biodynamic union...
s, the commonsensical understanding of Yoga
Yoga
Yoga is a physical, mental, and spiritual discipline, originating in ancient India. The goal of yoga, or of the person practicing yoga, is the attainment of a state of perfect spiritual insight and tranquility while meditating on Supersoul...
exercises, but specifically refers to the corporeal
Corporeal
Corporeal may refer to:*Corporeal undead, See also: :Category:Corporeal undead*Matter *Body, of or relating to the body*Corporeal...
conduct or seat of the wakefulness.
See also
- ConsciousnessConsciousnessConsciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...
- Dream argumentDream argumentThe dream argument is the postulation that the act of dreaming provides preliminary evidence that the senses we trust to distinguish reality from illusion should not be fully trusted, and therefore any state that is dependent on our senses should at the very least be carefully examined and...
- Lucid dreamingLucid dreamingA lucid dream is a dream in which one is aware that one is dreaming. The term was coined by the Dutch psychiatrist and writer Frederik van Eeden . In a lucid dream, the dreamer can actively participate in and manipulate imaginary experiences in the dream environment. Lucid dreams can seem real and...
- SleepSleepSleep is a naturally recurring state characterized by reduced or absent consciousness, relatively suspended sensory activity, and inactivity of nearly all voluntary muscles. It is distinguished from quiet wakefulness by a decreased ability to react to stimuli, and is more easily reversible than...
- SleepwalkingSleepwalkingSleepwalking, also known as somnambulism, is a sleep disorder belonging to the parasomnia family. Sleepwalkers arise from the slow wave sleep stage in a state of low consciousness and perform activities that are usually performed during a state of full consciousness...
- Sleep inertiaSleep inertiaSleep inertia is a physiological state characterised by a decline in motor dexterity and a subjective feeling of grogginess immediately following an abrupt awakening. The impaired alertness may interfere with the ability to perform mental or physical tasks...