It is always argued that all psychiatric disorders maybe due to known organic cause, unknown organic cause or due to other psychosocial factors. Cerebral disease, brain injury or brain disorders due to alcoholand drug abuse are some of the disorders that attack the brain. Due to these organic disorders there maybe dysfunction in perception thought contents, or mood and emotion, or in the overall pattern of personality and behaviour and cognitive functions maybe minimal. While some of these disorders are seemingly irreversible and progressive, others are transient or respond to currently available treatments.
Dementia is usually of a chronic progressive disorder due to death of neurons, in which there is disturbance of cortical functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgement and interferes with personal activities of daily living, such as washing, dressing, eating, personal hygiene, excretory and toilet activities. This disorder is seen in above 65 years of age in medical conditions like Alzheimer’s, Vascular Disease, HIV, Huntington’s disease, Creutzfeldt-Jakob disease and others.
Amnesia is other prominent impairment of recent and remote memory. While immediate recall is preserved, the ability to learn new material is markedly reduced.
Delirium is disturbances of consciousness and attention, perception, thinking, memory, psychomotor behaviour, emotion, and the sleep-wake cycle. It may occur at any age but is most common after the age of 60 years. The delirious state in most cases recover within 4 weeks or less. However, delirium lasting, with fluctuations, for up to 6 months is not uncommon.
Other mental disorders due to brain damageincludes brain dysfunction due to primary cerebral disease, endocrine disorders such as Cushing’s syndrome or other somatic illnesses, and to some exogenous toxic substances or hormones.