What type of disorder is characterized by an acute, temporary disturbance of mental function?

The type of disorder characterized by an acute, temporary disturbance of mental function is delirium. Delirium typically manifests as sudden onset confusion, disorientation, and fluctuating levels of consciousness. It is often triggered by medical conditions, substances, or severe stress, and its effects can be reversible once the underlying cause is addressed. This differentiates delirium from chronic mental illnesses, which are persistent and long-term, such as mood disorders or schizophrenia, and other options that either represent anxiety or compulsive behaviors. Delirium requires immediate attention to identify and treat the cause, making it distinct from disorders that do not present with such acute alterations in mental status.