There are 2 subtypes of delirium based on altered psychomotor activity. The hypoactive subtype is characterized by psychomotor retardation, patient drowsiness, and reduced arousal. The hyperactivity subtype is often overly alert and agitated, with prominent autonomic hyperactivity. In addition, the hyperactive subtype most often presents with delusions and perceptual disturbances such as hallucinations. About half of the patients with delirium have a mixed type, with components of both subtypes or fluctuating between them. Only about 15% of patients are strictly hyperactive. Those who are young, have the overactive subtype and have an etiology related to substance abuse have a shorter hospital stay and a better prognosis. Common disorders include dementia syndrome, mania, and depression. Psychomotor activity deterioration is a subtype of delirium with 2 types based on altered psychomotor activity. The main causes are metabolic disorders, drug intoxication and withdrawal, infections and fever, acute stroke, and epileptic abnormalities caused by various factors. Stroke delirium is a nonspecific consequence of any acute stroke, but confusion often resolves within 24 to 48 h after cerebral infarction. Persistent delirium can be caused by atopic stroke including occlusion of the right middle cerebral artery damaging the frontal and posterior parietal regions, and occlusion of the posterior cerebral artery resulting in bilateral or left-sided occipitotemporal (sphenoid gyrus) lesions. The latter lesions often involve the right hemisphere and can slowly progress and lead to agitation, visual field changes, and even Anton (denial of visual deficit) syndrome. Delirium can also occur following occlusion of the anterior cerebral artery or rupture of an anterior communicating artery aneurysm involving the anterior part of the cingulate gyrus and the phrenic region. Delirium is often present in older adults with fractures, and delirium is present in 50% of patients hospitalized with hip fractures. Orthopedic patients with suspected fat embolism should be checked for fat in urine, sputum, or cerebrospinal fluid. Anemia, thrombocytopenia, and disseminated intravascular coagulation (DIC) in hematologic disorders can lead to delirium. Finally, heat stroke, electric shock injury, and high temperature can also be the cause of delirium.