Causes of ADHD - Genetics
Margaret V. Austin, Ph.D., edited by C. E. Zupanick, Psy.D.What Causes ADHD?
Researchers investigate the causes and cures of many diseases and disorders. Thus, ongoing ADHD research has attempted to answer the question, "What causes ADHD?" Because of this research, we now know a great deal more about ADHD than we did 10 years ago (See section on New and Exciting Brain Research). Despite this large body of research, the specific cause of this disorder remains uncertain.
The vast majority of researchers conclude that ADHD is primarily a neurological or brain-based disorder. It is either present at birth, or it develops early on in childhood. Although our everyday surroundings can affect the severity of symptoms, these environmental factors do not seem to be the primary cause of the disorder.
Is ADHD inherited and caused by genetics?
Research has established that genetics play a powerful role in many behavioral symptoms. These include behavioral symptoms observed in ADHD: impulsiveness, hyperactivity, and inattention. The estimated heritability of ADHD (i.e., the proportion of a trait that can be attributed to genetics) ranges from 75 to 91%. This does not mean a parent of an ADHD child must have ADHD. It does mean that the gene for ADHD exists in the family line of one of the biological parents. The specific gene has not yet been identified.
Twin studies support a genetic basis for ADHD. Concordance rates (the occurrence of similar traits) are higher among identical twins (58-82%) than fraternal twins (31%-38%). (Martin, Scourfield, & McGuffin, 2002). Interestingly, when one twin has ADHD, but the other does not, the 'normal' twin is still more likely to have problems with impulse control. Although genetics play a key role in ADHD, the specific genes have not yet been identified.
While twin studies provide the strongest evidence of a genetic influence, studies of brain chemistry lend further support. These studies investigate what happens in the brain when people take medications used to treat ADHD symptoms. Stimulant drugs increase brain activity. Initially, experts thought ADHD was a result of an overactive brain. Therefore, it seemed counter-intuitive to give stimulant drugs to someone who has problems with inattention, hyperactivity, and impulsivity. The unexpected, calming effect of these drugs baffled experts. To explain this paradox, experts theorized that stimulant medication must have some unique and opposite effect on children with ADHD.
It turns out that ADHD is not a result of an overactive brain as once assumed. In fact, quite the opposite is true. Research has determined that ADHD is actually a result of reduced brain functioning (particularly frontal lobe) and decreased levels dopamine. Dopamine is a naturally occurring chemical in the brain that creates sensations of arousal and pleasure. In other words, children with ADHD have cognitive 'sluggishness,' or a slower thinking process than their peers. In children with ADHD, stimulants raise the brain activity to a level more comparable to their peers. In people with ADHD, stimulants also increase their ability to screen out irrelevant stimuli, control impulsive behavior, and to focus on the designated task.
Can parents help prevent ADHD in their children?
The short answer is no. Parents cannot 'prevent' ADHD any more than they can prevent their hair color: It's genetic. However, there are many things caregivers and families can do to enable the success of their ADHD children.
That said, there are ways to help children to do their best. Since complications of pregnancy have been linked to ADHD, good prenatal care is a great way to start looking after your child's health. Eat healthy, avoid alcohol and drugs, and see your doctor regularly to make sure you are doing everything within your power to give your baby a healthy start in life.
Are there other causes of ADHD?
ADHD is recognized as a genetic condition that is passed from parents to children. As no one can choose their genetics, there is nothing parents can do to prevent ADHD. However, caregivers and teachers can do things than can lessen the severity of ADHD symptoms. Likewise, various situational factors can worsen ADHD, or create similar symptoms in people without the disorder. For instance, a calm, quiet environment promotes concentration while a noisy, chaotic location diminishes our ability to focus on any one thing.
Do prenatal and postnatal factors affect ADHD?
The root causes of ADHD are biological. Nonetheless, certain factors may increase the severity of symptoms. These are: prenatal and perinatal complications (e.g., low birth weight, fetal distress); prenatal alcohol or tobacco exposure; lead poisoning and pesticides; moderate to severe protein deficiency; head injuries that involve the frontal lobe; allergies; abuse or other violent trauma. These stressors must be examined more fully to determine their exact connection, if any, to ADHD.
Resources
-
Articles
-
Childhood ADHD Overview
- Introduction to Attention Deficit Hyperactivity Disorder (ADHD)
- Signs & Symptoms of ADHD
- ADHD Signs and Symptoms: Attention Difficulties
- ADHD Signs and Symptoms: Hyperactivity
- ADHD Signs and Symptoms: Impulsivity
- Are There Different Types of ADHD?
- The Social, Educational, Financial & Occupational Impact of ADHD
- What are the Legal Rights of Caregivers and Their Children with ADHD (USA)?
- A Positive Spin: Is There Anything Good about ADHD?
- Signs of ADHD in Children at Home
- Signs of ADHD in Children at School
- Signs of ADHD in Children in Peer Relationships
- How Do I know if My Child Needs an ADHD Evaluation?
- What Should I Do If I Think My Child Might Have ADHD?
-
ADHD Discoveries and Controversies
- ADHD: New and Exciting Brain Research
- ADHD: New and Exciting Brain Research - Part II
- Neurotransmitter Changes with ADHD
- Executive Functions
- Neurodiversity: Is ADHD a True Mental Disorder?
- ADHD Statistics
- Cultural and Gender Differences in Prevalence Rates
- Should Children with ADHD Be Medicated?
- New and Promising Areas of Research
- Causes of ADHD in Children
- ADHD or Another Condition?
-
Diagnosis of ADHD in Children
- Who Can Diagnose ADHD?
- How Does ADHD Multi-Source Assessment Work?
- Assessment Instruments: Behavioral Checklists
- Assessment Instruments: Intelligence Tests
- Assessment Instruments: Achievement Tests (or Academic Tests)
- Assessment Instruments: Tests of Attention
- Assessment Instruments: Memory and Other Common Tests
- Step 2: Clinical Interviews
- Step 3: Physical Exam and Medical History
-
ADHD Treatment in Children
- Multimodal ADHD Treatment Approach
- ADHD Medications
- Treating ADHD with Stimulant Drugs
- Commonly Prescribed ADHD Stimulant Medications
- Treating ADHD with Non-Stimulant Drugs
- Risks of ADHD Medication
- Risks of ADHD Medications - Part II
- Benefits of ADHD Medication
- Side Effects of ADHD Medications
- Medication Decisions and Medication Management
- How Long Should ADHD Medication Treatment Last
- Psycho-Education about ADHD and Its Management
- Family Therapy
- Individual and Cognitive Behavioral Psychotherapy for the Child with ADHD
- Skills Training
- Social Skills Training and Coaching
- Supports
- Alternative ADHD treatment: What Does NOT Work?
-
Family and Personal Supports
- Effective Disciplinary Techniques
- Learn about Resources and Be Proactive
- Manage Stress, Self-Regulation & Provide Order
- Develop Routines, Organization and Expectations
- Communicate and Collaborate with Schools
- Express Confidence in Your Child's Abilities
- Help Children Improve Social Skills and Peer Relationships
- Avoid Homework Battles and Monitor Medication
- I Think I have ADHD. What should I do?
- I Think I Have ADHD - Part II
- Famous People with ADHD
- Adult ADHD Overview
-
Diagnosis of Adult ADHD
- How is Adult ADHD Diagnosed?
- Diagnostic Challenge 1: Looking into the Past
- Diagnostic Challenge 2: ADHD versus Similar Disorders
- Diagnostic Challenge 2 - Part II
- Diagnostic Challenge 3: ADHD Symptoms
- Diagnostic Challenge 3 - Part II
- Diagnostic Challenge 4: A Concealed Disorder
- Specialized Tests and Tools
-
Adult ADHD Treatment
- ADHD Medication Treatment
- Stimulant and Non-Stimulant Drugs for Adult ADHD
- Medication Timing, Dosage, Monitoring, and Duration of Treatment
- Weighing the Risks and Benefits of Adult ADHD Medications
- Psychotherapy for ADHD
- Coaching/Supported Employment for Adult ADHD
- Social Skills Training for Adult ADHD
- Psycho-Education and Cognitive Behavioral Therapy (CBT)
- ADHD Resources and References
-
Childhood ADHD Overview
-
Questions and Answers
- Does This Sound Like Bipolar?
- Do I Have Adult ADD?
- Why do I See Words and Numbers in my Mind...
- ADD Maybe?
- How do I Get Medical Treatment for my Medicine Refill Without Insurance?
- Is There Something Wrong With Me?
- I Can't function Normally Anymore, Can More Diagnoses issues Risk Survival?
- Bipolar Teen Son, ........
- Is My Daughter ADD?
- ODD and Risperdal
-
34 more
- If There's Nothing New, There's Nothing Good.
- Mystery Symptoms
- Bipolar Disorder and ADHD
- How To Help My Son
- Anger
- Depression in College Seniors
- Odd Eating Behavior
- 5 Year Old Behavior-Is it ADHD or Bipolar or Both?
- odd (ADHD)
- Attention Deficit and Depression
- What Should I do? Noah
- 16 year old girl with Attention Deficit Disorder
- Thoughts
- Diagnosed ADHD at 13, now being told I have bipolar disorder
- ADHD in Twins
- Inherited ADHD
- How to get off Focalin
- new diagnosis
- am i off my head i feel i have no feelings and want to harm ppl
- 17 yr old refuses help with bi-polar disorder
- Is Depression a Factor in Children With ADD?
- IS ADHD CAUSING HIM TO FAIL?
- heightened sexual behavior in my 8 yr. old with adhd
- seperation anxiety disorder or environment?
- my 7 year old nephew
- my daughter
- Do I have adult ADD?
- Fantasy land for attention
- 13 Yearl Old
- ADD
- Misdiagnosed and Lied To
- Funding Treatment (Without Insurance)
- Can ADHD Turn Into Bipolar?
- How Long To Diagnose ADHD?
-
Tests
-
Book & Media Reviews
- 10 Simple Solutions to Adult ADD
- A Walk in the Rain With a Brain
- ADD-Friendly Ways to Organize Your Life
- ADHD & Me
- ADHD Grown Up
- ADHD in Adults
- ADHD Nation
- Attention Deficit Disorder
- Attention-Deficit/Hyperactivity Disorder
- Buzz
-
29 more
- Driven to Distraction
- Facts About ADHD Children
- Healing ADD
- Helping Hyperactive Kids
- I Am Not Joey Pigza
- Joey Pigza Loses Control
- Joey Pigza Swallowed the Key
- Learning Outside the Lines
- Making ADD Work
- Medicating Children
- Mind Fields
- New Look at ADHD: Inhibition, Time, and Self-Control
- Non-Drug Treatments for ADHD
- Overcoming ADHD
- Parenting Children With ADHD
- Reclaiming Our Children
- Rethinking ADHD
- Ritalin is Not the Answer Action Guide
- Ritalin Nation
- Running on Ritalin
- Should I Medicate My Child?
- Taking Charge of ADHD, Revised Edition
- The Explosive Child
- The Gift of Adult ADD
- The Little Monster
- The Science of ADHD
- Thumbsucker
- Treating ADHD and Comorbid Disorders
- What Would Joey Do?
-
Links
-
Videos
- How to Select the Best School Accommodations for Your Child with ADHD
- How to Manage ADHD and Anxiety
- What You Need to Know about Students with ADHD and Anxiety
- ADHD and Eating Right
- Tourette Syndrome and ADHD
- Homework, Organization, and Time Management Strategies to Help Kids with ADHD
- Nutrition in Support of ADHD Treatment
- Behavioral Therapy: What it is and finding a therapist
- Project-Based Learning and ADHD
- Conditions May Mimic ADHD
-
102 more
- Department of Education Guidance Broadens Understanding of 504 Rights for Kids with ADHD Part I
- Treating ADHD in the African American Community
- How to Build Self-Motivation in Teens with ADHD
- Goal Setting and Keeping for the ADHD Brain
- Neurofeedback Treatment for ADHD
- ADHD in Preschoolers: What to Look For and How to Help
- FYI on ADHD Evaluations
- Teaching Grit, Perseverance and Frustration Tolerance to Students with ADHD
- Does my Child Have ADHD?
- How to Start Eating Well When You Have ADHD
- 5 Solutions for Common ADHD Social Struggles
- Is My High School Student Ready for College? (And Is My College Student Ready to Go Back?)
- Understanding and Applying the Science of Time Management
- ADHD Medication and College Students: Prevent Misuse, Abuse, and Diversion
- Improve Homework Time with Strategies That Work For ADHD
- Student Voices: What Really Matters to Young Adults With Learning and Attention Issues
- 5 Ways Nutrition can Impact ADHD Symptoms
- 3 Tips for Adjusting to a New Diagnosis of ADHD
- Creating the Best Learning Environment for Students with ADHD
- ADHD & Executive Functioning
- Department of Education Guidance Broadens Understanding of 504 Rights for Kids with ADHD Part II
- Ask The Expert: Neurofeedback Treatment for ADHD
- ADHD and Suicide Risk Factors
- The Choice is in the Details: Medication Options for ADHD
- Understanding and Supporting Young Adults with ADHD
- Helping Your Young Adult Become Independent
- Creating Structure and Routines for Children with ADHD
- When You and Your Child Have ADHD - Communication Skills to Resolve Conflict
- Guidance for Uncertain Times: Navigating Relationship Challenges
- Guidance for Uncertain Times: Mindful Parenting
- Couples with ADHD: Creating Caring Connection amid the Chaos
- Disclosure and Workplace Accommodations for Individuals With ADHD
- A Summer At Camp
- Self-Advocacy Tips For Teens With ADHD
- ADHD and Curbing Impulsive Spending to Help Your Relationship
- ADHD: Signs, Symptoms, Research
- ADHD & Risk of Adult Drug Use
- Health and Life Expectancy in ADHD
- Focus on ADHD
- Pediatrics: ADHD and Food Allergies
- ADHD: It's a Family Affair
- Does Your Child Have ADHD?
- ADHD in Children
- Living with ADHD
- Rise in ADHD Cases in Children
- Why is Dating Difficult When You Have ADHD
- Video Games, Screens, and ADHD A Potent Mix
- Ask the Expert Helping Children with ADHD LD Conquer Chronic Stress
- Ask the Expert: Mindfulness, Stress, & Emotion
- Attention Deficit Hyperactivity Disorder
- Ask the Expert Educator Edition: ADHD & Executive Functioning
- Ask the Expert - Academic Evaluations - What Parents Need to Know
- ADHD and Sibling Relationships
- Medication Treatment for ADHD
- Using Time Out
- Treating Childhood ADHD
- ADHD-friendly Summer Family FUNdamentals
- Preparing Older Teens for the Road Ahead
- Tips for Teachers: Tailoring homework to make a difference
- Your Active Preschooler: Could it be ADHD?
- Tips for Teachers: Creating a positive dialogue with parents of students with ADHD
- Helping Parents & Kids Understand the Social & Emotional Aspects of ADHD
- Social and Emotional Concerns of Children with ADHD: Strategies to Help
- Holiday Gifts for Children with ADHD
- Behavior Management and Combined Treatment for Children with ADHD
- Setting Realistic School Expectations for Students with ADHD
- On Their Own: Helping College Students with ADHD
- Children's Communication Challenges: Is it Attention, Language or Both?
- Out-of-School: Parenting During the Summer
- ADHD in the Workplace: Finding Success
- Emotions and Motivation in ADHD
- The Role of Medication in Managing Children's ADHD Symptoms
- Top Tips for Combating Stigma and Addressing Myths about ADHD
- Facts and Myths about ADHD
- What To Do If Your Child Has ADHD?
- How Common is ADHD?
- Children, Meds, and Heart Safety: A Tale of ADHD and Public Health
- ADHD & Your Child’s Transition to College
- Your Teen with ADHD: Challenges and Strategies for Success
- Ask the Expert - No more homework battles
- A Frontline to ADHD
- Understanding Girls with ADHD
- What is ADHD?
- What To Do When Your Child With ADHD is Bullied
- Stop the Chaos! Tips for Creating a Peaceful Household When Mom has ADHD
- Is It ADHD?
- Ask the Expert - What else can I do? Complementary approaches to ADHD treatment
- All in a row: Getting your kids with ADHD organized
- Your Student With ADHD Was Admitted to College, Now what?
- Evidence-based treatment for ADHD in young children
- Home life when Mom or Dad has ADHD: Succeeding with your family
- How does technology affect ADHD?
- Diagnosing ADHD
- Helping Your Child Successfully Handle Change
- Recognizing challenging behaviors in young children: Could it be ADHD?
- Classroom Managment Supports for ADHD Behaviors in Preschool Settings
- Getting through to your teenager with ADHD
- What Everyone Should Know about ADHD
- Make Learning Exciting: Apps for Executive Functioning
- Teenagers, ADHD, and Substance Abuse
- Past Procrastination -- Get Your Kids Organized, Focused and Motivated
- Ask the Expert: Late, Lost, and Unprepared: How to Help Your Child with Executive Functioning
-
More Information
Topics
-
Related Topic Centers
-
Addictions
-
Aging & Elder Care
-
Assessments & Interventions
-
Career & Workplace
-
Emotional Well-Being
-
Life Issues
-
Parenting & Child Care
-
Abuse
-
ADHD: Attention Deficit Hyperactivity Disorder
-
Adoption
-
Autism
-
Child & Adolescent Development: Overview
-
Child & Adolescent Development: Puberty
-
Child Development & Parenting: Early (3-7)
-
Child Development & Parenting: Infants (0-2)
-
Child Development & Parenting: Middle (8-11)
-
Child Development & Parenting:Adolescence (12-24)
-
Child Development Theory: Adolescence (12-24)
-
Child Development Theory: Middle Childhood (8-11)
-
Childhood Mental Disorders and Illnesses
-
Childhood Special Education
-
Divorce
-
Family & Relationship Issues
-
Intellectual Disabilities
-
Learning Disorders
-
Oppositional Defiant Disorder
-
Parenting
-
Self Esteem
-
-
Psychological Disorders
-
Anxiety Disorders
-
Bipolar Disorder
-
Conversion Disorders
-
Depression: Depression & Related Conditions
-
Dissociative Disorders
-
Domestic Violence and Rape
-
Eating Disorders
-
Impulse Control Disorders
-
Intellectual Disabilities
-
Mental Disorders
-
Obsessive-Compulsive Spectrum Disorders
-
Personality Disorders
-
Post-Traumatic Stress Disorder
-
Schizophrenia
-
Sexual Disorders
-
Somatic Symptom and Related Disorders
-
Suicide
-
Tourettes and other Tic Disorders
-