What Is ADHD?
Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed neurodiversity seen in children, affecting anywhere between 8% and 13% of the population worldwide.
Symptoms of ADHD Vary Considerably Among Individuals
Some people with ADHD exhibit symptoms of hyperactivity and/or impulsivity, whereas others struggle to focus their attention, especially in traditional learning environments. Some children with this disorder have difficulty with emotional regulation, whereas others are more likely to find sitting still to be a challenge.
ADHD is significantly more common in males, and approximately half of all children diagnosed with it will continue to experience symptoms well into adulthood. The age of onset, developmental course, and responsivity to pharmaceutical and/or behavioral treatments also vary among individuals.
Although the world may be becoming more accepting of neurodiversities and schools may be more flexible in their curricula, children and adults with ADHD may still find it difficult to thrive. Different individuals respond differently to therapies, making it challenging for those seeking assistance. Low self-esteem, depression, anxiety, sleep disorders, and substance-abuse disorders are more common in those with ADHD than in neurotypical individuals.
Treatment for ADHD has traditionally involved a combination of behavioral therapy and drug therapy. The most commonly used medications are stimulants, including Ritalin, Concerta, Focalin, Metadate, and Adderall. Although these drugs have proved helpful for increasing focus and reducing hyperactivity for some, they don’t work for everyone. Furthermore, they can cause unwanted side effects, and the effects of taking these drugs long-term still aren’t clear.
The ability of stimulants to reduce hyperactivity was discovered accidentally in the 1930s—not from the ridiculous animal experiments that are performed today.
What Are the Causes of ADHD?
The exact causes of ADHD are still unknown. What we do know from decades of research with human volunteers is that it’s a “polygenic” condition, which means that a number of genes are involved in the manifestation of physical and behavioral characteristics observable in individuals. For example, small variations in genes that affect the functioning of dopamine, serotonin, and other neurotransmitters in the brain can increase an individual’s risk for developing the disorder.
We also know that environmental influences—including in utero exposure to neurotoxic substances, birth complications, obesity, diabetes, asthma, epilepsy, visual problems, and autoimmune diseases—also appear to put children at a higher risk for ADHD.
Most Individuals Who Develop ADHD Have Both Genetic and Environmental Risk Factors
In other words, ADHD is a very complex condition with variable symptoms, multiple genetic and environmental risk factors, and frequent psychiatric and physical comorbidities.
Can Animals Have ADHD?
ADHD is a human-specific condition, and other animals don’t exhibit symptoms the way they appear in humans. However, many experimenters still try (and fail) to induce symptoms in mice and rats.
ADHD Experiments on Mice, Rats, and Owls
Experimenters have tried everything from breeding hyperactive rats to genetically engineering animals to have genes that interfere with brain development or neurotransmitter function.
In other experiments, young animals are deliberately exposed to a host of harmful substances, including lead, nicotine, alcohol, pesticides, and methamphetamine. Other experimenters purposely deprive developing mice and rats of oxygen by putting them in oxygen-deprivation chambers. Some experimenters have injected neurotoxins directly into the brains of baby rats, whereas others force mice to endure social isolation in order to cause extreme stress.
In an absurd and cruel test known as the Morris water maze, animals are dropped into a pool of water and forced to swim frantically in order to find a platform hidden under the surface.
Believe it or not, an experimenter at Johns Hopkins University has been using barn owls in a cruel attempt to study attention deficits in humans. To do this, he breeds the birds, restrains them in tubes or jackets, inserts electrodes into their brains, and then bombards them with lights and sounds. Needless to say, how the brain of a captive barn owl forced into a straightjacket responds to stimuli has little relevance to how the human brain processes and attends to information.
While all these animal “models” of ADHD have resulted in hundreds of thousands of sick and miserable animals, none truly mimics the complex condition that is human ADHD.
In a survey of 121 animal studies claiming to investigate ADHD, only five were found to be in any way relevant to the hypotheses of the medical articles in which they were cited. The authors of the survey concluded that “animal research has contributed very little to contemporary understanding of ADHD.”
Fortunately, some researchers are using non-invasive methods to study ADHD in humans. Advanced neuroimaging and genetic tools are unlocking the complex mystery of attention disorder without harming animals.
Critically, funds must be shifted away from experiments on animals and toward providing patients with greater access to mental health care.
For an accurate diagnosis of suicidality, depression, alcohol problems, or other mental illnesses, consult a qualified healthcare professional. If you are in crisis or think that you may have an emergency, call your doctor or 911 immediately. If you’re feeling suicidal, thinking about hurting yourself, or concerned that someone you know may be in danger of hurting themselves, call the National Suicide Prevention Lifeline at 1-800-273-TALK (1-800-273-8255). This free service is available 24 hours a day, seven days a week, and is staffed by certified crisis-response professionals. If you’re located outside the U.S., call your local emergency line immediately.