ADD (Attention Deficit Disorder) is one of three types of ADHD (Attention-Deficit Hyperactivity Disorder), a neurobehavioral developmental disorder primarily characterized by "the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone" and symptoms starting before seven years of age.

While the term ADD is still used by laymen, it was formally changed to ADHD predominantly inattentive (ADHD-PI or ADHD-I) in 1994 with the publication of Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). The other two types of ADHD are ADHD Predominantly hyperactive-impulsive and ADHD Combined hyperactive-impulsive and inattentive.

Comparison chart

ADD versus ADHD comparison chart
Edit this comparison chartADDADHD
Medical Classification Attention Deficit Hyperactive Disorder, Inattentive Type (ADHD-I). ADD is not a medical or psychological diagnosis. ADHD is of 3 types, ADHD-I (erstwhile ADD); ADHD, Predominantly Hyperactive-Impulsive Type; and ADHD, , Combined Type: Inattentive and hyperactive/impulsive
Male to Female ratio 2:1 4:1
Symptoms Have trouble paying attention, finishing tasks, or following directions, are distracted; appear forgetful, careless and disorganized; and frequently lose things. Might or might not display significant attention problems, appear restless, fidgety, overactive and impulsive. They “act before thinking” and often “speak before thinking” by blurting out and interrupting others.
Behaviour Sluggish and slow to respond and process information, have difficulty sifting through relevant and irrelevant information. Day dream and may be shy or withdrawn. This activity is consistent and not only in a certain setting. People with these hyperactive/impulsive behaviors may play and interact loudly. They have difficulty staying in their seat, talk excessively, and have trouble waiting turns. They may seem to be perpetually “on the go.”
Stands for Attention Deficit Disorder Attention Deficit Hyperactivity Disorder


PET scans show that patients with ADHD had lower levels of dopamine transporters in the nucleus accumbens, a part of the brain's reward center, than control subjects.
PET scans show that patients with ADHD had lower levels of dopamine transporters in the nucleus accumbens, a part of the brain's reward center, than control subjects.

ADHD is a developmental disorder in which certain traits such as impulse control lag in development. Using magnetic resonance imaging of the prefrontal cortex, this developmental lag has been estimated to range from 3 to 5 years.

The delay is prominent in the frontal cortex and temporal lobe, which are believed to be responsible for the ability to control and focus thinking. In contrast, the motor cortex in the ADHD patients was seen to mature faster than normal, suggesting that both slower development of behavioral control and advanced motor development might be required for the fidgety behavior that characterizes ADHD.

Symptoms and Diagnosis

The American Medical Association concluded in 1998 that the diagnostic criteria for ADHD are based on extensive research and, if applied appropriately, lead to the diagnosis with high reliability.

The DSM-IV criteria are listed below:

Six or more of the following signs of inattention have been present for at least 6 months to a point that is disruptive and inappropriate for developmental level:


  1. Often does not give close attention to details or makes careless mistakes in schoolwork, work, or other activities.
  2. Often has trouble keeping attention on tasks or play activities.
  3. Often does not seem to listen when spoken to directly.
  4. Often does not follow instructions and fails to finish schoolwork, chores, or duties in the workplace (not due to oppositional behavior or failure to understand instructions).
  5. Often has trouble organizing activities.
  6. Often avoids, dislikes, or doesn't want to do things that take a lot of mental effort for a long period of time (such as schoolwork or homework).
  7. Often loses things needed for tasks and activities (such as toys, school assignments, pencils, books, or tools).
  8. Is often easily distracted.
  9. Often forgetful in daily activities.

Six or more of the following signs of hyperactivity-impulsivity have been present for at least 6 months to an extent that is disruptive and inappropriate for developmental level:


  1. Often fidgets with hands or feet or squirms in seat.
  2. Often gets up from seat when remaining in seat is expected.
  3. Often runs about or climbs when and where it is not appropriate (adolescents or adults may feel very restless).
  4. Often has trouble playing or enjoying leisure activities quietly.
  5. Is often "on the go" or often acts as if "driven by a motor".
  6. Often talks excessively.


  1. Often blurts out answers before questions have been finished.
  2. Often has trouble waiting one's turn.
  3. Often interrupts or intrudes on others (example: butts into conversations or games).

II. Some signs that cause impairment were present before age 7 years.

III. Some impairment from the signs is present in two or more settings (such as at school/work and at home).

IV. There must be clear evidence of significant impairment in social, school, or work functioning.

V. The signs do not happen only during the course of a Pervasive Developmental Disorder, Schizophrenia, or other Psychotic Disorder. The signs are not due to some other another mental disorder (such as mood disorder, anxiety disorder, dissociative identity disorder, or a personality disorder).


ADHD is the most commonly studied and diagnosed psychiatric disorder in children, affecting about 3% to 5% of children globally and diagnosed in about 2% to 16% of school aged children. 5% of American adults are estimated to live with ADHD.

In the United States, ADHD's prevalence varies substantially by state, from a low of less than 5% in Nevada to highs greater than 11.1% in states like Tennessee and Louisiana.
In the United States, ADHD's prevalence varies substantially by state, from a low of less than 5% in Nevada to highs greater than 11.1% in states like Tennessee and Louisiana.

By Gender

ADHD occurs two to four times more commonly in boys than girls (male to female ratio 4:1 for the predominantly hyperactive type vs. 2:1 for the predominantly inattentive type). In the United States, boys (13.2%) are more likely than girls (5.6%) to have been diagnosed with ADHD.

By Age

ADHD inattentive type is subtle in nature, likely to manifest about at 8 to 9 years of age, while ADHD predominantly hyperactive, impulsive and combined type is usually obvious by 5 years of age and peaks in severity between 7 to 8 years of age.

In the United States

A C.D.C. study of children’s health issues, conducted from February 2011 to June 2012 whose results were published in April 2013, revealed that while historically ADHD affected 3-7% of children, the rates are much higher now.

Fifteen percent of school-age boys have received an A.D.H.D. diagnosis, the data showed; the rate for girls was 7 percent. Diagnoses among those of high-school age — 14 to 17 — were particularly high, 10 percent for girls and 19 percent for boys. About one in 10 high-school boys currently takes A.D.H.D. medication, the data showed.
The figures showed that an estimated 6.4 million children ages 4 through 17 had received an A.D.H.D. diagnosis at some point in their lives, a 16 percent increase since 2007 and a 53 percent rise in the past decade. About two-thirds of those with a current diagnosis receive prescriptions for stimulants like Ritalin or Adderall, which can drastically improve the lives of those with A.D.H.D. but can also lead to addiction, anxiety and occasionally psychosis.

Medical prognosis

Children diagnosed with ADHD have significant difficulties in adolescence. Those affected are likely to develop coping mechanisms as they mature. ADHD persists into adulthood in about 30-50% of cases.

ADHD inattentive type affects the cognitive development and remains through out life. With maturation, these behaviors progressively decline and often have been "outgrown" by adolescence. However, impulse issues remain well into adulthood.

Adult ADHD

A good 4% - 5% of adults in the United States (i.e. 8 million adults) are said to have ADHD. Adult ADHD can be the continuation of childhood ADHD. Even though ADHD affects boys at higher rate than it does girls in childhood, this ratio seems to even out by adulthood.

Adults with ADHD may have difficulty concentrating, staying organized, following directions, remembering information, or completing work within time limits. If these difficulties are not managed appropriately, they can cause associated behavioral, emotional, social and professional problems.

Adults with ADHD are more likely to perform poorly and change employers frequently, have less job satisfaction and fewer occupational achievements.


ADHD cannot be ccompletely cured, but many of the symptoms that interfere with functioning and cause distress can be controlled with a combination of medication (Concerta, Ritalin, Adderall, and Vyvanse, among others) and psycho-social therapy. Organization aids like calendars, planners, task managers and timers are other ways to help people with ADHD function better.

Opinions and controversies

Opinions regarding ADHD range from, not believing it exist at all - to believing that there are genetic and physiological bases for the condition. Most healthcare providers accept that ADHD is a genuine disorder with debate in the scientific community centering mainly on how it is diagnosed and treated.

A combination of therapy and medication is prescribed. Stimulants like chain substituted amphetamine are commonly prescribed medications for ADHD. Although "under medical supervision, stimulant medications are considered safe", the use of stimulant medications for the treatment of ADHD has generated controversy because of undesirable side effects, uncertain long term effects and social and ethical issues regarding their use and dispensation.


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