Attention deficit hyperactivity disorder (ADHD) is a chronic condition made up of behavioral symptoms that include inattentiveness, hyperactivity, and impulsiveness. ADHD affects around 6.4 million children in the United States and often continues into adulthood.

ADHD is more common in boys than girls but is equal among men and women, which suggests girls may be under-diagnosed during childhood. ADHD symptoms usually begin before age 12.

Schizophrenia is a long-term mental health condition that affects how a person thinks, feels, and behaves. Schizophrenia affects around 3.5 million individuals in the U.S.

Schizophrenia is slightly more common in males than females. Symptoms may begin between ages 16 and 30.

Although ADHD and schizophrenia have many differences, there is also an overlap in symptoms and some similarities between the two disorders.

ADHD and Schizophrenia Links
ADHD symptoms have been reported in individuals who develop schizophrenia in adulthood. Sometimes these symptoms are also seen in their children.

Some possible links that have been found between ADHD and schizophrenia in studies include:

• ADHD is diagnosed in numerous children at genetic risk of schizophrenia
• People with schizophrenia often have symptoms of other psychiatric disorders in early adolescence and ADHD is one of the most frequently reported
• Childhood ADHD diagnosis may be more a better predictor of adulthood schizophrenia than depression
• Children with ADHD are at a high risk of developing a wide range of psychiatric disorders
• Children and teenagers with ADHD could be 4.3 times more likely to develop schizophrenia as adults than people without ADHD
• Stress-inducing factors may be associated with both ADHD and schizophrenia and may affect proper brain development of a child before birth
• ADHD and schizophrenia occurring together might be due to shared genetic factors
• Alternative forms of a gene that arise by mutation in people with schizophrenia are also found in ADHD.

Causes
The cause of ADHD is not clear. Factors that may be involved include:

• Genetics: Research indicates that ADHD can run in families and genes may play a role
• Environment: Environmental factors, such as exposure to toxic materials
• Development: Problems with the central nervous system at important stages of development

The cause of schizophrenia is unknown. Factors that may increase the chances of developing schizophrenia include:

• Genetics: Schizophrenia can run in families. Different combinations of genes might make people more at risk from the condition.
• Brain development: Research shows that some individuals with schizophrenia have subtle differences in brain structure.
• Neurotransmitters. An imbalance between the chemical messengers in the brain – dopamine and serotonin – may be connected to schizophrenia. Research shows that drugs that alter the levels of these chemicals relieve schizophrenia symptoms.
• Pregnancy and birth complications: A low birth weight, premature labor, or lacking oxygen during birth are more likely to have happened to people with schizophrenia before or during their birth.

Neurofeedback training, which enables the individuals to regulate their brain activity using a real-time feedback loop, has long been known as a suitable soliton for symptoms of ADHD, and neurofeedback is increasingly been investigated as a potential alternative intervention for schizophrenia. This study aimed to explore the effect of short but intensive neurofeedback training for schizophrenic patients with difficulty for long-time training. For example, a middle-aged woman with chronic schizophrenia completed the intensive training of alpha/beta2 (20–30 Hz) in four consecutive days with a total training duration of 13.5 hours. The results showed that her alpha/beta2 increased over sessions, and her behavior performance including short-term memory, mood, and speech pattern was improved at the end of neurofeedback training. Importantly, a 22-month follow-up found a dramatic improvement in both positive and negative symptoms. These positive outcomes suggest that such intensive neurofeedback training may provide new insight into the treatment of schizophrenia and thus deserves further study to fully examine its scope.