Brain "disorders"

What's in a label?

Ask Pamba

Trends in Education

On Neuroplasticity

Learning changes the brain

On José Martí

"Pensar es servir"

Word and Mind

Every mind is creative

"Every mental state has a corresponding brain state, consisting of a particular pattern and sequence of neural processes. Until recently, most of these processes were undetectable, but the advent of high-tech imaging has made the visible, with the result that mental disorders are increasingly being recognized as neurological brain disorders." Rita Carter in The Human Brain Book 2009

In this video, neuroscientist Vilayanur S. Ramachandran describes some brain anomalies that help us to understand our extraordinary brain.

Here are some of the mental and brain states that are commonly identified as disordered.

ADD (attention deficit disorder)

According to the Canadian Mental Health Association, people with attention deficit disorder (ADD) are inattentive and overly impulsive, have more difficulty than most people sitting still or remaining attentive, and may seem overactive.

ADD is a genetic disorder. Harvard psychiatrist Edward Hallowell has linked attention deficit traits, which are not genetic, to the pervasive presence today of electronic media.

ADHD (attention deficit hyperactivity disorder)

ADHD is one of the behavioural disorders that is most common in childhood, but which may persist into adulthood. Symptoms include persistent difficulty paying attention and/or hyperactivity. ADHD tends to run in families. In most cases, the underlying cause is thought to be genetic, but predisposition interacts with factors such as exposure to toxins, brain injury before birth or early in life, and food allergies.

ADHD may be grouped into three general types:

Inattentive - associated with short attention span, poor concentration, and difficulty following instructions and staying on task.

Hyperactive/impulsive - associated with fidgeting, excessive activity, excessive talking and interruptions, and impulsive actions.

Combined - associated with symptoms of both inattentiveness and hyperactivity.

Low dopamine levels have sometimes been associated with ADHD, and drugs such as Ritalin, which increase dopamine levels, are sometimes prescribed.

ADT (attention deficit traits)

Attention deficit traits (ADT) have reportedly often been misdiagnosed as attention deficit disorder (ADD) because they appear similar to the symptoms of ADD.

However, ADD is genetic and ADT is not. Modern neuroscience has linked the increase in ADT to the proliferation of electronic media and consequent changes to the brain. A plastic brain is changeable and vulnerable. A young brain particularly vulnerable to environmental influences during its critical periods of formation, during which the signature activities of the culture shape the brain.

Anxiety Disorders

It is normal to experience symptoms of anxiety in stressful situations; they are usually occasional, temporary, and appropriate. However, when cognitive, physical, and behavioural symptoms of anxiety occur in ordinary situations, occur frequently, and are experienced to a degree that interferes with everyday life - at work, at school, or in social relationships - they are usually beyond the normal range.

In most cases, the causes are not known, but they may include physical causes such as substance abuse or a thyroid disorder, traumatic life events, bereavement, etc. The brain processes underlying anxiety disorders are also unknown.

Types of anxiety disorders include phobias, panic disorder, obsessive-compulsive disorder (OCD), acute stress disorder, and post-traumatic stress disorder (PTSD).

Alzheimer's Disease

Alzheimer's is a progressively degenerative condition and the most common cause of dementia. Although the symptoms and progression of this brain disorder vary from person to person, its earliest symptoms include increasing forgetfulness which may be mistaken with normal symptoms of aging.

Alzheimer's progresses to severe memory loss, unstable moods, and personality changes, among other symptoms. In its later stages, memory loss, confusion, and mental instability become more severe, and physical symptoms such as incontinence and abnormal reflexes may be evident.


Norman Doidge describes the brain as "asymmetrical" when exceptional abilities exist alongside serious disabilities. Barbara Arrowsmith Young's story illustrates this phenomenon.

Characteristic impairments include problems with communication, social skills, and restricted, repetitive behaviour. Brain regions affected have been identified, but the cause of these abnormalities are unknown and there is no cure for these disorders. Problems usually appear early in childhood, before the age of three.


Children with autistic disorder typically don't respond to their name or speech directed at them, and avoid eye contact and physical contact. They start talking late, and speak with an abnormal tone or rhythm. They develop strict routines and have difficulty coping when they are changed. Other symptoms include repetitive behaviours (e.g., rocking), abnormal responses to social cues (e.g., faces and voices). While some may ignore sensory stimuli, others are unusually sensitive to sound, light and touch. Seizures are not uncommon. Many autistic children have learning disabilities. However, some may have exceptional abilities, for example, in rote memory, while others may be savants, for example, in mathematics.

Symptoms are similar but less severe in children with Asperger's. Their language and speech abilities develop on time, but they have problems with social skills. They also develop inflexible behaviour and routines, and have difficulty coping when routines are changed.

Body Dysmorphic Disorder

Body dysmorphic disorder (BDD) is a type of illness that involves body image. The person with BDD is preoccupied with a physical defect that is imagined or minor. People with this disorder are concerned with a specific body part and see themselves as "ugly." Common areas of concern are skin, hair, facial features, and body weight. Their level of anxiety eventually affects their social, work, and personal lives.

Brain Lock

Psychiatrist Jeffrey Schwartz uses the term brain lock to refer to the cycle of obsessive thoughts and compulsive behaviour that characterizes OCD (obsessive-compulsive disorder). Three parts of the brain are involved in obsessions.

1. The orbital frontal cortex, in the lower area the frontal lobe, triggers the "mistake feeling" and sends a signal to the cingulate gyrus.

2. The cingulate gyrus, which lies immediately above the corpus callosum, the large bundle of nerves that connects the right and left hemispheres, triggers the anxiety that something dreadful is going to happen, and sends signals to the gut and heart that cause panic.

3. the caudate nucleus, another structure deep in the brain, normally allows our thoughts to transition from one to the next, but in OCD, the caudate malfunctions.

Because the caudate is stuck, the orbital frontal cortex and the cingulate gyrus keep firing off signals, creating a "worry circuit" and increasing anxiety to disabling levels in the person with OCD. Schwartz calls this phenomenon brainlock.

He developed a therapy that helps the person with OCD to understand the brain process that causes brainlock, and to heighten self-awareness. It includes relabeling the problem they're experiencing - e.g., "My problem isn't germs, it's my OCD"; and refocusing their attention to "manually" transition to the next thought to "unlock" their brain - e.g., get started on a positive, enjoyable activity.

Capgras Delusion

Capgras delusion, or Capgras syndrome, is a disorder in which someone looking at a parent, spouse, friend, etc., perceives that person as an identical-looking imposter. This disorder may result from mental illness, but may also be the result of brain injury, in which case, the condition appears to heal itself. Recognizing a person or object involves an emotional response, which engages the amygdala, part of the limbic system - the emotional center of the brain.

When the connection between the visual and emotional systems is severed, the person with Capgras syndrome concludes that identical-looking imposters have replaced the parent, spouse or friend. In one of Ramachandran's case studies, the individual with Capgras syndrome recognized the parent telephoning from an out-of-view location because the connection between the auditory and emotional systems had not been damaged.

Cerebral Palsy

Cerebral palsy refers to a group of disorders that affect movement, posture, speech, etc., and may sometimes cause learning disabilities. It may be the result of brain before or around birth, or the failure of the brain to develop properly; however, often the cause is not identified. Possible causes include lack of oxygen to the fetus, infections, brain injury, or brain hemorrhage. This disorder is not progressive.

Charles Bonnet Syndrome

Visual loss of varying degrees is common among the elderly. Charles Bonnet syndrome in a condition that causes mentally healthy patients with visual loss or impairment to have vivid, recurring, and complex visual hallucinations. This condition was described by Charles Bonnet in 1760, and introduced into English-speaking psychiatry in 1982. While Charles Bonnet syndrome predominantly affects older people with visual impairments, it can also result from damage to the eyes or visual system. Oliver Sacks gives an interesting, informative and clear explanation of this syndrome in his TED Talk on hallucination.


According to the Centre for Addiction and Mental Health, depression is not simple unhappiness or something depressed individuals can "get over" by by their own effort. There are different types of depression. Generally speaking, it is "a complex mood disorder caused by various factors, including genetic predisposition, personality, stress and brain chemistry." A depressed person experiences persistent feelings of intense sadness, hopelessness, and despair, and loses interest in life. The main symptom of depression, a sad, despairing mood, is present most days, last most of the day, lasts more than two weeks, and interferes with everyday life - at work, at school, or in social relationships.

In many cases, the cause of depression is not obvious. Triggers include illness, hormonal changes - e.g., during pregnancy or after childbirth - traumatic life events, and bereavement. Various biological abnormalities have been found in the brains of depressed people, including decreased levels of the neurotransmitter serotonin, and abnormal patterns of neural activity in the amygdala and parts of the prefrontal cortex.

Down Syndrome

Down syndrome is a chromosome abnormality that affects both physical and mental development. Individuals with Down syndrome have 47 chromosomes, instead of 46 (or 23 pairs). The cause is unknown, but maternal age is a risk factor. Symptoms include slow motor and language development and learning difficulties. Individuals with Down syndrome have lower than average life expectancy, but some live to old age. As adults, they are at increased risk for eye problems such as cataracts, as well as increased risk of Alzheimer's.


There are different types of dysgraphia. Generally speaking, it is associated with impaired handwriting. Impaired motor skills make it difficult for individuals with dysgraphia to control writing movements. Dysgraphia is also a working memory problem associated with the storing of written words and processing the letters in those words. Individuals with dysgraphia have difficulty encoding auditory and visual information into letters and words. They often have difficulty putting ideas into writing, may leave out words, or may use the wrong words. They often need frequent verbal cues.

OCD (obsessive compulsive disorder)

OCD is characterized by cognitive distortions, that is, inaccurate or exaggerated thoughts and ideas, that build up to a degree of disabling anxiety that does not go away. Intrusive thoughts produce apprehension, fear, or worry - e.g., fear of germs. The resulting anxiety produces repetitive behaviours aimed at reducing the anxiety associated with germs - e.g., compulsive handwashing. People with OCD may become further distressed by the realization that their obsessions and compulsions are not rational or reasonable. See brain lock.

ODD (oppositional defiance disorder)

Sometimes called Conduct Disorder, ODD is a behavioural disorder. The behaviour of the child or adolescent with ODD is persistently and repeatedly antisocial. Studies suggest there is reduced brain activity in the area of the brain linked to shaping behaviour through responses to rewards and punishments (i.e., the right orbitofrontal cortex). Early intervention (e.g., talk therapy) has a greater likelihood of proving effective.

Factors that increase the risk of ODD include an unstable or violent home environment, physical and/or sexual abuse, bullying, social rejection, etc. Genetic factors, learning disabilities, attention deficit disorder, depression and other mental health issues also increase the risk of ODD.

Symptoms of ODD vary, but they include aggressive behaviour, rules violations, vandalism, theft, physical cruelty, persistent lying, truancy, alcohol or drug abuse, etc. These persistent and repetitive behaviours may last months or years, and usually result in low self-esteem, problems with social skills, and academic as well as behavioural problems at school.

Parkinson's Disease

Parkinson's is caused by degeneration in areas of the brain that control muscles and movement. It is a progressive brain disorder and the underlying cause is generally unknown. Symptoms develop gradually and include tremors and rigid muscles, as well as problems with movement and balance.

Phantom Limb Syndrome

Your body image is something that is constructed in your brain. Every part of your body's surface is mapped in the brain and has a corresponding area in the somatosensory cortex. Sometimes a person experiences the presence of a limb, even after it has been amputated. The limb cannot be seen, but it can be felt, and it often causes excruciating pain.

Phantom Pain

For most amputees, an amputated or phantom limb can cause chronic pain that may persist for the rest of their lives. Following injury, damage to tissues, nerves and brain maps before amputation may produce the sensation of pain in an area of the body after it has been amputated. The pain is experienced in the amputated limb when the problem is in the brain. V.S. Ramachandran's mirror box has helped some patients eliminate phantom pain.

PTSD (post-traumatic stress disorder)

PTSD is a mental disorder affecting individuals who have experienced or witnessed highly traumatic events such as war, torture, rape, murder, suicide, etc. Symptoms of PTSD include flashbacks of the traumatic event, recurrent thoughts and images, nightmares, depression and anxiety, social withdrawal, family violence, etc.

Worry Circuit

See brainlock above.