Physical illness and disability
Common conditions include cancer, heart disease, kidney disease, diabetes, genetic disorders, and blood disorders such as hemophilia and cystic fibrosis (a congenital disease that causes digestive and respiratory problems).
Physical disability may affect the locomotor system, bones, joints, or muscles. Motor handicap can result from injury to the central nervous system. When this occurs, speech disorders and intellectual delay often follow.
Sensory disability
This includes deafness or partial hearing loss, blindness or partial sight (visual capacity below 1/10).
Intellectual disability
This occurs when someone's intellectual development has been arrested and genuine recovery is unlikely. Their abilities may remain intact in other areas—emotional, artistic, and others.
Mental illness
Psychiatric disorders affect higher functions: attention, memory, mood (sadness or euphoria), judgment, and emotional capacity. The term "illness" suggests that change is possible—improvement, recovery, and sometimes deterioration.
Every classification has limits. Illnesses and disabilities often overlap and blend together. The response of family, society, school, and workplace shapes how someone develops and improves. The essential point is this: there is always something that can be done.
A brief glossary:
Autism: a global developmental disability that prevents normal communication;
Muscular dystrophy: a hereditary illness causing progressive muscle wasting;
Epilepsy: a neurological disorder marked chiefly by seizures;
Alzheimer's disease: an illness causing progressive intellectual decline (memory loss, sleep disturbance, etc.);
Neurosis: a disorder of emotion or affect (anxiety, phobia, obsession) of which the person is aware and which does not impair their judgment.
Cerebral palsy: varies in severity and may affect movement, intellectual development, the senses, and behavior.
Psychosis: a mental illness that severely disrupts a person's relationship with reality, of which they are unaware.
Schizophrenia: a psychosis marked by psychological disintegration, loss of contact with reality, and withdrawal into oneself.
Multiple sclerosis: a chronic, slow disease of the central nervous system causing progressive paralysis.
Down syndrome: (formerly called mongolism): a genetic anomaly caused by the presence of an extra chromosome.
Spina bifida: a congenital malformation of the lower spinal cord that may cause paralysis of the lower limbs and loss of sphincter control.
Traumatic brain injury: an injury that may cause motor and/or psychiatric disturbances.