Delta brain waves oscillate between 0 Hz and 4 Hz (cycles per second) and are regarded as the slowest brain waves that humans can produce. They are typically produced during the deep stages of sleep (stage 3 and stage 4) and are involved in regulating unconscious bodily processes such as heart beat regulation, kidney functioning, and digestive functioning.
It is thought to help the body with healing and is thought to release various hormones including human growth hormone (HGH) at various frequencies. There are many benefits associated with having optimal delta wave functioning. These include: getting a better night’s sleep, boosted immune system functioning, as well as increased empathy.
Delta waves are typically generated in the right hemisphere of the brain and are linked to our subconscious and unconscious processes. Younger kids tend to have more delta activity and as we age delta activity becomes increasingly sparse – even during sleep. While you are in a delta state of functioning, you have no conscious awareness.
Delta Brain Waves: What do they do?
Delta waves are the lowest in regards to frequency, but are the highest in amplitude of all brain waves. They are primarily involved in unconscious processes and help us get the deepest, restorative sleep possible. Unless you are a child and/or have severe ADHD, you likely will not experience any delta activity while you are awake. Below is a list of some experiences, conditions, and hypotheses related to delta brain waves.
- Advanced healing: The delta brain wave rhythm is known to be very restorative. This is the primary state of consciousness that you enter during the deepest stages of sleep. Delta waves help restore bodily and rejuvenate the mind. If you are injured whether its physically or mentally, delta is the brain wave that helps restore your body back to its natural homeostasis.
- Anti-aging: It has been suggested that delta waves actually release various hormones that promote slower or anti-aging processes within the body. These hormones that help restore the body include: DHEA as well as melatonin. It is unclear as to how much delta waves help with anti-aging. Obviously if these hormones are released from delta production, they may help restore the body and prevent a stress response from taking over.
- Deep sleep: When you enter your deepest sleep, delta activity slows down your metabolism and helps restore both your mind and body. Among individuals that deal with chronic stress, the delta state may not be reached. Thus the stressed out individuals may wake up and they won’t feel restored at all. This is the slowest wave sleep and is often referred to as “SWS” or “slow wave sleep” among researchers.
- Empathy: People that have a deep sense of empathy for others tend to produce slower brain waves during empathetic states. They may produce theta waves in addition to very slow delta waves. It is the slow brain wave activity that allows individuals to really get a sense of others’ emotions and relate to the person based on how they are feeling.
- GHB production: Delta waves tend to increase the production of gamma-hydroxybutyric acid – a naturally occurring substance in the central nervous system of humans. It has neuroprotective properties and is thought to help protect cells from hypoxia and other damage.
- Growth hormone (HGH): Some have suggested that HGH (human growth hormone) is released at certain frequencies in the delta range. This means that while you sleep, your body is able to enter a state of relaxation which is the ideal state for the secretion of HGH. Some would argue that deep delta sleep is the best way to promote natural release of HGH by the pituitary gland.
- Immune system: Ever notice when you get sick and sleep you typically feel better the next day? This is because when your body and mind relax in the deepest levels of delta sleep, your immune system functioning improves. Most people do not notice improvements in recovery from a sickness during the daytime, they notice after a full night’s sleep. This is because the delta waves play a huge role in immune system functioning.
- Intuition: When you have a “gut” reaction to a certain event or experience, it is typically an automatic or unconscious response from your body. If you are able to trust your intuition, it means that you trust your body’s natural response. This is primarily a result of slow wave activity in the theta and/or delta range.
- Learning disabilities: If a person’s brain is producing large quantities of delta activity while they are awake, they may experience learning disabilities or ADHD. The delta frequency range may make it extremely difficult for an individual to focus. It has been found that individuals with various types of brain injuries tend to produce delta during waking hours – making it extremely difficult for the individual to perform conscious tasks.
- Unconscious mind: Delta waves are linked with the unconscious – meaning responses that cannot be consciously controlled. Bodily functions that are regulated unconsciously include the beat of the heart, breathing, kidney function, digestion, etc. Every process that is unconsciously regulated is associated with delta activity.
Delta Brain Waves Research
- Age affects delta: In general, the younger an individual is, the more likely they are to have higher amounts of delta. As we age, delta activity tends to significantly decline. Newborn babies tend to have a lot of slow wave activity simply because their brains have not developed enough to facilitate conscious thought. As the infant continues to grow and their brain evolves, delta activity is reduced, and their brain waves tend to speed up to greater frequencies. Delta is a dominant brain wave among infants. Delta waves tend to decline during adolescent years by about 25%. In the elderly / senior citizens, they may not produce any delta activity even during sleep – it may be entirely absent from the EEG.
- Disorders: Individuals with brain functioning problems may have irregular delta activity. For example, in some cases of ADHD, brains of individuals are producing abnormally large quantities of delta and theta waves when they should be producing faster beta waves. Other problems including paranomnias involve delta irregularities. Sleep walking and sleep talking tend to occur while delta production is high. Additonal diseases and disorders in which delta plays a role include: diabetes, Parkinson’s and schizophrenia. Various brain injuries may result in an individual producing excessive delta brain waves – making concentration and learning extremely difficult.
- Gender differences: On average, females have been shown to have more delta wave activity than males. This holds true across all species of mammals, but noticeable differences do not typically appear until early adulthood (e.g. 30’s or 40’s in humans). Men tend to show significantly more restricted delta wave activity than females. Some hypothesize that this may be in part due to the fact that men tend to have larger skull sizes.
- Production: Delta waves typically are found in the thalamus or in the cortex. During sleep, delta waves tend to be dominant in the right hemisphere of the brain. Delta waves are also thought to be dominant in the thalamus to help coordinate reticular formation. Lesions to the brain are thought to disrupt delta production.