Irina Dashevsky-Kerdman PhD, BCN

 

Specialization

Learn more about the conditions Dr. Kerdman specializes in and unlock your true potential.

 

Addiction

Neurofeedback is the most important new treatment for addiction.

Addiction is a seriously debilitating mental health disorder. If left unchecked, addiction strips people of their self-respect, their ability to function optimally, their relationships, their reputation, careers, and their soul.

It’s a disease that affects thinking – and causes a person to engage in a behavior that is self-destructive and painful. It’s often accompanied by anxiety, depression, bi-polar, and other mental health disorders.  Loved ones often believe erroneously that addicts are weak … that curing addiction is a matter of self-discipline. People, who struggle with addiction, report feelings of shame, guilt, remorse, anger, and frustration. For many it’s a brain disease that is very hard to change..

Research shows that most addiction treatment programs fail. Their collective success rate is abysmal. They have a “revolving door” as people relapse and come in and out of treatment. Many people leave before completing the programs.

Neurofeedback is the most important new treatment for addiction.

Using neurofeedback combined with other addiction treatments dramatically increases the success rate of treatment.

Addiction is physiological, not psychological.

Because addiction is a brain disorder, not a moral issue or just a lack of discipline, I work directly with the brain to retrain patterns of dysfunction by teach it to remain calm, relaxed and focused. Training helps support more clear thinking. This builds a strong foundation for recovery and relapse prevention. Medications can help temporarily, and short-term that may be a good thing.

The problem is medications don’t teach a person how to cope. They may help with accompanying disorders but do not correct them.

People struggling with addictions learn to rely on substances to help them feel calm, or to pay attention or to manage mood. Medications are yet another substance.

How Neurofeedback Helps

Neurofeedback training helps teach one how to calm down. It helps you connect to the reasonable, rational regions of the brain during stressful times. When people gain control of their own emotions, they can start choosing the option to remain clean and sober.

There have been several research studies that show those who use neurofeedback as part of an addiction treatment program, in fact, show much higher success rates and much lower relapse rates than the same program without neurofeedback. This appears to be true for every age group.

In my practice I advocate support groups, talk therapy, and behavioral interventions. However, adding neurofeedback trains people to be more calm, to better manage moods and emotions, and to sleep better. This tremendously reduces the problem of “white knuckling” the recovery. Without addressing these problems effectively, traditional programs produce higher relapse rates.

Brain Training is an approach that can help you learn to gain self-control by decreasing stress, increasing reasoning, and override irrational thoughts that make abuse so compelling. It helps overcome the problem. Although the complications with addiction can make training more complex, dealing with the networks in the brain that are malfunctioning and restoring them to more normal neurological patterns, helps to correct the underlying physiological manifestation of addiction.

We know that people suffering from addiction don’t choose this disease. They want to learn new ways of dealing with it. With the help of a brain map (a representation of the brain that maps out areas of over/under arousal and connectivity or lack of if throughout the brain) we can map out areas of concern and target for correction.

How does brain training teach the brain?

Neurofeedback effectively improves mood, anxiety, impulsivity, and behavior through consistent reinforcement of the state the brain is in when it is calm and focused. This is a normal state for the brain. Through neurofeedback the brain learns to return to normal regulation and balance.

During neurofeedback the client is rewarded and, through feedback, is made aware when the brain is producing the proper brain waves, reducing malfunctioning and, as a result, maladaptive behaviors. Without reinforcement it would be impossible to know when you were practicing the proper balance, which would allow you to improve regulation.

What type of results can I expect from brain training?

Surveys of health professionals, who use neurofeedback in their practice, estimate that over 85% of their clients successfully learn to focus, regulate behavior, and decrease impulsivity when they train on a consistent schedule.

Once the learning goal is achieved, we work with the client and his physician to decrease medications, where applicable, while decreasing his training schedule. Many individuals are able to decrease medications and training all together, while some are left with the minimal dose and a maintenance training schedule.

We also have several other tools available that compliment and often optimize the training experience. Depending upon the individual client, these tools may assist by increasing the impact of neurofeedback and at times shortening the duration of training. Please contact us for an individual consultation.

 

Anxiety & Panic Disorders

Learning how to turn off chronic stress responses is life changing.

Usually anxiety results from one’s response to stress. The stress can be psychological, physiological, dietary, and/or environmental. Once a person gets locked into a pattern of anxiety, it can be hard to break.  Learning how to modulate chronic stress responses can be life changing.

There are various forms of anxiety. Sometimes it manifests as excessive worrying, a nagging sense of fear, restlessness, overly emotional responses, negative thinking, catastrophizing, and defensiveness. Anxiety is involved in addiction, perfectionism, being overly controlling, and behavioral issues.

Anxiety sufferers are often overwhelmed, exhausted, and stressed. Some can’t concentrate due to their intense internal focus. Others ruminate about specific things. Anxiety is easily detected if someone appears outwardly nervous. At other times, anxious people can appear calm but their brain seems to never quiet. These people can’t stop thinking; they can’t shut their brain down. The constant internal chatter can get so bad that it interrupts their sleeping and steals their quality of life. They find it difficult to live in the present, as they constantly worry about the future or live in the past.   

Helping people learn to calm or quiet themselves is by far the best and most effective solution for anxiety. Learning to decrease anxiety gives suffers hope as they take control of their lives.  Biofeedback and EEG neurofeedback are two of the quickest and fastest ways we teach people to learn to help themselves and it’s easy to learn. These technologies have been used for many years with solid proven results. One can learn how to decrease anxiety and remain calmer with neurofeedback. Learning this life-long skill decreases the need for dependence upon medications.

What medications don’t teach.

Patients with anxiety are often prescribed medications. But, medications can’t teach one to quiet his or her mind. Although there may be one or more areas in the brain causing anxiety, Neurofeedback training identifies and targets specific problematic areas and connectivity of the brain, while medications generally affect the entire brain, often resulting in side-effects.

Medications only work when taken, so patients become dependent upon them to decrease anxiety. When a person stops medications, it is likely the anxiety will remain. Certain classes of medication are addictive, therefore, improper titration can produce withdrawal symptoms. On the contrary, Neurofeedback strengthens the brain connectivity that results in self regulation.

I often treat patients who are struggling getting off their anti-anxiety medication(s). Neurofeedback has proven to help this process. As the brain learns to self-regulate, which often decreases anxiety, less medication is needed. Proper, medically supervised titration is imperative, though.

Over the years, technology and brain science have made incredible advances.  Researchers and practitioners apply this knowledge and continue to hone neurofeedback technology into an increasingly more effective teaching tool. With brain training one learns to modulate their response to stress so that anxiety is minimized and occurs less frequently.

How does Neurofeedback reduce anxiety?

Simply put, as you brain train you watch your brain waves live on our EEG monitor. As you learn to reduce anxiety and increase calmness, you can watch your brain waves change. With our coaching, you learn to recreate that state. With the proper amount of training. the brain learns to hold onto healthier patterns. Learning to correct anxiety- producing neurological patterns occurs with awareness, practice, and reinforcement.

Neurofeedback facilitates awareness, provides reinforcement, and allows one to monitor the quality of practice during a training session. Because we are hardwired to return to homeostasis, patients can learn to decrease and/or eliminate anxiety. As learning improves, patients can begin decreasing their training schedules. Most can stop training once they reach their goals and the training gains are holding. A small number of patients with persistent, extremely resistant or complex issues require occasional “tune ups” or a significantly reduced maintenance training schedule. 

 

ADD, ADHD, Impulsivity, Behavior & Attention Problems

ADD is a brain problem -- it’s not a psychological issue.

ADD, ADHD, Impulsivity, Behavior & Attention Problems

When a person struggles with ADD, others often see symptoms like distractibility, impulsivity, inattention, or lack of follow-through as a result of laziness or lack of effort.

If ADD were laziness or lack of effort, doctors wouldn’t prescribe medications. They do so because ADD is a neurological issue -- it’s not a psychological one, yet, it may cause psychological disturbances.

Medications may help, but only temporarily and they do not teach one how to be calm and focused, or to behave.  In addition, even the best talk therapy and behavioral interventions can seem to make minimal progress with challenging kids.  Neurofeedback can help almost anyone learn to gain self-control and improve attention.   

Medication concerns

As it comes to children, many parents have concerns about medication side effects.  The list of these can be long, but can include a loss of appetite (especially in growing children) cardiac risks, interference with sleep, or even becoming “less personable.”  There’s also a concern that children are taught that pills can solve their problems.

The longer someone takes medication, the larger the risk of side effects. One can build up a tolerance to medication, which means that prescriptions change, or the dosage is increased, or additional medications are added.  This can also increase the risk of side effects. 
 

Brain Training helps overcome the problem

Most people are unaware that brain training can better regulate focus while decreasing distractibility, impulsivity, and behaviors which are annoying to teachers and loved ones. So, out of desperation, people, seek artificial chemical control.
 

The Problem with the ADD Brain

Stimulants appear to slow down a hyperactive client and help him or her focus. That is so because with hyperactive ADD there may be too much slow activity in brain regions that regulate focus and attention.

ADD clients compensate for this slower than normal brain activity by stimulating their brains with constant body movement to “wake their brain up”. Stimulants increase brain activity so one can focus without the constant body movement. Slow activity in certain brain regions is also associated with lack of motivation, distractibility, inattention, depression, and worry.

brain wave adhd.jpg

Excessive fast activity in the brain can also cause problems.  That can include impulsivity, aggressiveness, and anxiety. The brain is racing so fast that it’s difficult to listen or sit still. People with ADD are often very intelligent. They often get the big picture right away.  Because their mental pace may be faster than the person giving the instructions, they move ahead and miss many details.   

Brain Training is an effective and researched alternative.

Because ADD is a brain problem, it make sense to work directly on the problem,

The brain drives all learning.  When patients train their brain with neurofeedback, they learn how to become focused, calm, and to gain self-control.   

Most people can’t control the number of heart beats they make per minute.  It’s also hard (without brain training) to learn to control the rhythm of the brain. If the brain’s waves are “not in sync” or are too fast or slow, it’s very hard to focus, be calm, or be in control. 

The good news is various studies conducted over many years show that brain training with neurofeedback improves inattention, distractibility, impulsivity and self control.

How does brain training teach the brain?

The brain is a self-regulating feedback loop.  These loops form networks ranging from resting to attentional. When one area of the brain is out of sync, these networks become disturbed.

Neurofeedback effectively improves attention and behavior through consistent reinforcement of the state the brain is in when it is calm and focused. This is a normal state for the brain. Through neurofeedback the brain learns to return to normal regulation and balance.

With neurofeedback the client is rewarded and made aware when the brain is producing the proper brain waves, reducing excessive fast or slow activity. Without reinforcement it would be impossible to know when one was practicing the proper balance which would allow one to improve self-regulation.

For example, when one learns to a catch a ball and is rewarded by catching it, over time catching a ball becomes easier. It is no longer a conscious decision to think through the steps learned to catch a ball. It becomes somewhat automatic and the more one practices the better one gets. Similarly, once a person learns to pay attention and practice it, he or she won't forget. 

What type of results can I expect from brain training?

Surveys of health professionals using neurofeedback estimate that over 85% of their clients successfully learn to focus, regulate behavior, and decrease impulsivity when they train on a consistent schedule.

Once learning is achieved,  we work with the client and his physician to decrease medications while decreasing his training schedule. Many individuals are able to decrease medications and training all together while some are left with the minimal dose and a maintenance training schedule.

We also have several other tools available that compliment and often optimize the training experience. Depending upon the individual client, these tools may assist by increasing the impact of neurofeedback and at times shortening the duration of training.  Please contact us for an individual consultation.

 

Autistic Spectrum (ASD)

Neurofeedback produces more positive change in more symptoms for autistic children than any other intervention

Why is neurofeedback so important for anyone who is on the autistic spectrum developmental delays? Neurofeedback often produces more positive change in symptoms of autistic children than any other intervention. For clinicians and families who have worked with this modality, the changes can be profound.

Most people on autistic spectrum become easily overwhelmed. Sensory integration work is often very helpful. But it’s so much more efficient to train the brain itself to calm. There are specific areas of the brain that play a role in self-calming. If they don’t work well or are overwhelmed, the child (or adult) will have a very difficult time calming. By strengthening the parts of the brain that calm through training, it gives every other technique the chance to work better.

The changes that most people notice first, once training starts are: 1) improved sleep, and 2) the ability to self-calm (or self-regulate).

Most people have a hard time understanding how it is possible for an autistic spectrum child to train their brain. Yet this group responds so consistently to brain training. For most kids, changes aren’t subtle – they have a big impact on the lives of the family and the child. Why? Neurofeedback trains more organized, better regulated brain activity. The brains of children on the autistic spectrum have clear patterns of dysregulation. It is usually evident on qEEG analysis.

Often, the most disorganized brains often show the most improvement, because they have the furthest to improve. Ever subtle changes can show up as changes in the person’s behavior. The more neurofeedback training one does, the more the individual learns to self-regulate. However, it doesn’t take that many sessions for the family members to notice changes.

Other Changes

When you help improve self-regulation, and when the brain starts to calm down and become better regulated, many other symptoms start to improve. These include eye contact, attention, and becoming more interactive and engaging with other people.

 

Depression

It’s when you can’t lift yourself out of it that depression becomes a problem.

SSRI medications are considered “standard” solutions for depression. And while medications are an absolute necessity for some, recently mental health professionals have become increasingly aware of the limitations of medication and psychotherapy for depression.

Problem with reliance on medications:

  1. Many individuals still struggle.

  2. Once on anti-depressants, it is hard to get off them as the brain becomes reliant on medication. This makes it more difficult to get out of depression or become motivated on one’s own.

Brain training in depression

Thousands of health professionals – psychologists, psychotherapists, psychiatrists, and neurologists now use neurofeedback with their clients.

How do you train mood and depression?

A great deal of research shows evidence of a neurological basis for depression. Certain image patterns often correlate to depression (see example below).

qEEG offers brain diagnostics. This can help identify connectivity issues in the brain to target and treat. After training, many depressed clients report changes in mood, motivation, and become more stable. They report being less susceptible to depression or moodiness.

Depressed or down?

Think of depression – or just chronically being down – as being “stuck.” Anyone can have an experience that gets them down or depressed. It’s when you can’t lift yourself out of it that depression becomes a problem. Even under difficult circumstances, many people can lift their mood. They may struggle, but not stay depressed.. When someone gets stuck, they can’t do that. They can’t break out of it on their own. Friends will say – “get a grip”, or “cheer up”. If one could, one would. When the brain is stuck in a pattern of being down, it’s not solely psychological. Research has shown physical patterns in the brain often correlate with depression.

A person can exercise his or her brain back to health and break up the ‘stuck’ pattern. Most patients report the impact of training on mood is very powerful. Often they notice being in a better mood within a few sessions. However, to stabilize mood regulation, more training is required. Training helps the brain practice a more efficient pattern of mood regulation. After all, the brain learns and then teaches us everything we know. It can learn to regulate mood.

The two images below (brain maps) are from different people. The map on the left is from a person with a long history of depression. On the left, there is a colored orange and yellow area. It represents an excess amount of slow brainwave activity. This pattern is often associated with depression. The picture on the right displays a relatively normal brain, without depression.

depression head.jpg

 

Heart Rate Variability

Heartmath and Coherent Breathing

Heart Rate Variability HRV

​Heart rate variability (HRV) is a physiological phenomenon where the time interval between heart beats varies. It is measured by the variation in the beat-to-beat interval. Other terms used include: "cycle length variability", and "heart period variability".  We work with this phenomenon by using techniques that involve learning how to breath more accurately/deeply, to bring calm to the whole system, and reduce stress overall.

The two primary techniques Dr. Kerdman uses are:

Heartmath

HeartMath is a unique system of rigorous scientific research, validated techniques, leading-edge products and programs, and advanced technologies for people interested in personal development and improved emotional, mental and physical health. HeartMath is internationally recognized for our practical solutions to transform the stress of change and uncertainty, and bring coherence and renewed energy into people’s lives.

Coherent Breathing

Coherent Breathing is a formal method and system for cultivating health, well-being, and longevity through breathing nd conscious regulation of certain psycho-physiological functions

 

Insomnia & Sleep Disorders

Neurofeedback is a powerful tool for helping people fall asleep and stay asleep

Sleep and Brain Training

At least 40 million Americans each year suffer from chronic, long-term sleep disorders.  An additional 20 million experience occasional sleep problems.

Neurofeedback is a powerful tool for helping people fall asleep and stay asleep. Over 3000 licensed health professionals such as psychologists and MD’s now use this new technology daily with patients.  As a group, they report significant and consistent improvements for client sleep problems. 

It’s often remarkable how quickly sleep can improve with clients who have been to many different specialists, and have struggled with sleep for years.  Falling asleep and staying asleep is clearly the job of the brain to do. 

The role of the brain and sleep

The brain regulates sleep. The EEG (brainwaves) clearly reflects changes in sleep stages. Training brainwaves using neurofeedback to decrease or increase slow brainwave activity, or to increase specific EEG activation patterns appears to help the brain normalize sleep. Based on reports from a large number of licensed health professionals the evidence shows that training the EEG impacts sleep regulatory mechanisms and people sleep better.

Since sleep is complex and involves many systems, it is not possible to suggest that sleep problems always improve as a result of neurofeedback. But clinicians say that they routinely expect changes to occur in sleep patterns after appropriate training for a large percentage of their clients. As with any program, a complete sleep assessment is helpful. Sleep hygiene issues (including caffeine, alcohol and other behavioral factors) and other potential contributory factors such as possible sleep apnea also need to be carefully reviewed and corrected in combination with neurofeedback training.

 

Learning Disabilities

Train the area of the brain involved in learning

Many techniques help teach someone with learning disabilities skills to compensate or work around their problems. 

Neurofeedback is different.  It is used to train the area of the brain involved in learning or performing certain skills, such as reading, math or auditory and visual processing. 

It is much easier to enhance learning skills when the brain works better.  That’s what neurofeedback training is about.  There are other training and regulation techniques that we also use in our center to enhance the brain’s capacity to learn. 

Recent research shows that learning involves coordination between multiple areas of the brain. These different areas of the brain communicate to each other at incredibly fast speeds.  When the timing between them is is off – even slightly, learning can be impaired. 

Neurofeedback has been used to train increased coordination and communication between different areas of the brain.  This improvement in timing is critical to learning.  Think about how hard it is to play tennis, golf or baseball if your timing is off.   It’s much harder to learn when the timing in the brain is off.  Brain training helps target and train those issues directly. 

 

Migraine

Neurofeedback can be very helpful for reducing migraines.

If you know a migrainer who is well controlled on medications and who doesn’t have major side effects from medications, he or she is not usually a candidate for neurofeedback. In general they are happy with having migraines under control and they won’t consider changing what they are doing. 

It is important to know that neurofeedback can be very helpful for reducing migraines. There are hundreds of cases that have been reported of migrainers who trained with neurofeedback that reduced the number and intensity of migraines they had.  Often health professionals report that medications have been reduced or at times eliminated. 

In addition we look at any number of factors and interventions that may be contributing to headaches.  My approach is  comprehensive based on extensive experience and research and can be highly effective. ​

 

Obsessive Thinking (OCD)

Why not change that part of the brain that is “stuck” so that it can turn off the constant repetition

Obsessive thinking (OCD)

If you can’t stop your brain from thinking about certain thoughts or repeating particular behaviors over and over again, it’s called OCD. 

A great deal of research has shown there are particular areas in the front of the brain that often are implicated in this problem.  When that part of the brain runs too slow or too fast, the person is unable to switch gears, or to put on the brakes.  Literally they can’t stop thinking or doing something even when they try.

Sometimes medications help, but often they don’t.  All medications have certain side effects that can occur.

A logical solution is – why not change that part of the brain that is “stuck” so that it can turn off the constant repetition of thoughts or behaviors can stop. 

That technology now exists – using neurofeedback.  Many clients and therapists who use neurofeedback have reported very good success in reducing OCD after training their clients.  In essence, it trains the individual to “shut it off.” 

Patients report after training, they don’t really have to work at shutting down thoughts or behaviors as much.  It just doesn’t happen as much – their mind is much more quiet.  Apparently the brain is able to manage these issues in a more normal way after training. 

 

Post Traumatic Stress Disorder (PTSD)

Training can also help target those areas of the brain implicated in PTSD

Post Traumatic Stress Disorder

PTSD is a form of anxiety where extreme life stress triggers a number of persistent symptoms. 

If you or someone you know has been diagnosed with PTSD, you’ve probably already tried other therapies and or medication.  Often, many symptoms remain. 

If neurofeedback was better known in the world of PTSD, it would be one of the first treatments used.  There are many cases of severe PTSD in which therapists and clients have reported “clients got their lives back” after training with neurofeedback.  These reports are not isolated. Reports from around the world in many disciplines such as psychiatrist, psychotherapist, and other mental health practitioners, have chimed in to give their positive responds when adding this type of technique to the regime of treating their PTSD clients. This is not isolated – these reports from around the world have come from psychiatrists, psychotherapists, and other mental health professionals.

It’s hard to overcome

Any relaxation technique, from hypnosis to yoga is useful to reduce stress.  For PTSD, many common forms of relaxation and stress just don’t have enough impact to overcome the problems. Medications are often introduced to help reduce symptoms.  But meds don’t change the underlying stress response. 

The problem is in the brain.  Something has triggered a severe stress response, which ends up producing a number of symptoms.  The person can’t turn it off.  How do you turn it off? 

Turn off the stress

Research has shown clearly that PTSD is a brain-based disorder.

By training the brain, the individual learns to increase calm, and to regulate how they respond to stress.   Training can also help target those areas of the brain implicated in PTSD.   In essence, it helps the individual learn to “calm their brain.”  Training is learning.  Once the client becomes skilled at calming, they can maintain that without further training.  Many professionals report this often reduces the reliance on medications.

During training, the first symptom usually noticed is improved sleep.  As more training occurs, other related PTSD symptoms start to improve.  Once symptoms are reduced and these gains hold for longer periods of time, training is gradually reduced until it’s clear the stability and calm is holding.  At that time, training can end.

 

Seizures & Epilepsy

Seizures are primarily a brain that loses its stability. Neurofeedback is proven to reduce seizures

Here’s a bold statement.  Every seizure patient should be given the chance to regulate his own brain – and not be completely reliant on seizure medication.  Medical professionals unfamiliar with neurofeedback perhaps may object.

But health professionals who have used it – including several thousand RN’s, psychologists, and MDs -- recognize the power of using brain training to help the individual become more stable. Increased stability is reported to correlate with decreased seizures.  Often, therapists report that the MD helps reduce seizure meds after they see the increased stability of a client. 

Seizures are primarily a brain that loses its stability.  Because there are 18 good studies showing the effectiveness of neurofeedback in reducing seizures, everyone should be given the chance to train.  They aren’t – because they aren’t told about it by the health profession who are primarily unaware of it.  It’s still considered new, though it’s been a around a while.

History of reducing seizures with neurofeedback

Neurofeedback was discovered during an experiment with cats.  Initially the cats did neurofeedback to show they could train their brain (they could).

In a later experiment, the cats whose  brains were trained had greatly reduced seizures after they were exposed to a chemical vs. normal cats with no brain training. 

Shortly after that, some labs starting training people who had seizures.  There have been over 18 studies that show that seizures are often reduced by brain training.

 

Stoke & Traumatic Brain Injury (TBI)

If you hurt your brain, you should do physical therapy directly on your brain.

The technology is now there to do that – and that’s what neurofeedback provides. 

Traumatic Brain Injury

For anyone who’s had a stroke or brain injury, relatively little formal rehab is offered once about 2 years post stroke.  Typically, it may be more physical therapy or speech therapy, or even occupational therapy.  But often, the big gains are expected in the first 2 years, and very minor slow gains occur after that. 

Many people continue to improve incrementally after 18 months, but there are few formal rehab programs that make a big difference.   The health profession has accepted the idea that the greatest recovery occurs in the first 18 -24 months.  They don’t even bother offering patients other options. 

Neurofeedback as an intervention for strokes and TBI

If your hurt your knee, you do physical therapy on your knees.

If you hurt your brain, you should do physical therapy directly on your brain.

The technology is now there to do that – and that’s what neurofeedback provides.  It helps the individual in fact exercise the brain directly. Training targets specific parts of the brain, based on the individual profile of each client.

Let’s take speech for example. If there’s a problem with speech, speech therapy is attempting to teach the person to learn how to speak again.

Neurofeedback tends to target training specific areas of the brain that relate to speech (for example, Broca’s or Wernicke’s area).  The goal is to strengthen the area and associated areas that are responsible for speech.  Because of the amount of speech recovery that can occur with neurofeedback, some neuropsychologists feel the brain there is actual rehab occurring in the brain – and that it’s not just dealing with compensating areas. 

Symptom improvement ranges from speech to movement to mood regulation to memory to control of behavior.  Headaches are often reduced.  Remember, each of these functions are regulated by the brain.