<unk>  is attributed to a range of various pathologies such as vascular and infectious midbrain, pontine and thalamic lesions, local subarachnoid hemorrhage, compression by tumors, basilar migraine, basilar vascular hypoplasia, and following regional surgical or angiographic interventions. These pathologies are mainly near the base of the brain and the hallucinations have gone away in patients that had their pathology corrected such as the removal of a tumor. The most commonly reported hallucinations are animals, people of any age, scary or deformed faces and heads, landscapes, or people walking in a line. Lesions The lesions that disturb brainstem reticular formation or thalamic targets seem to be the source behind<unk> . For example, lesions affecting the dorsal raphe system can lead to hallucinations by preventing ascending inhibition to the dorsal lateral geniculate nucleus (LGN). This inhibition may hyper-excite the LGN, inducing visual hallucinations. Lesions of the retina and areas proximal to it can remove or alter the inputs coming in from the external environment to the visual system.<unk>  therefore might emanate from disturbances in distal portions of the visual system. Lesions in the frontal and temporal lobes can also lead to complex visual hallucinations because the lobes connect to the visual system via the lateral geniculate nucleus and medial pulvinar. In addition, visual processing and salience can be disrupted by thalamic lesions which affect important structures such as the pulvinar. The effect lesions on the brainstem have on the ascending reticular activating system (ARAS) has also been hypothesized. It was proposed that since the ARAS plays a role in consciousness and waking, the lesions of the brainstem common to<unk>  may “disrupt ARAS impulses from the brainstem reticular formation” and, as a consequence, lead to the sleep disturbances characteristic of<unk> . The use of drugs such as Olanzapine may help treat sleep disturbances as it has been found to “improve sleep continuity, sleep quality, and to increase slow wave sleep.” Correlation between other diseases People diagnosed with Parkinson's disease, narcolepsy-cataplexy syndrome, delirium tremens, Lewy body dementia, and temporal lobe epilepsy are more prone to complex visual hallucinations such as<unk> .<unk>  is more common in patients with a long duration of Parkinson's disease and also with a long treatment history, depression, and cognitive impairment. Paranoid delusions are common in these patients even though the hallucinations can occur during clear sensorium. Differences from other visual hallucinations Other visual hallucinations tend to stem from psychological disorders. Whereas a person with a psychological disorder thinks their hallucinations are real, people with<unk>  normally know that the visual hallucinations they see are not real.<unk>  hallucinations are independent of seizures, unlike some other visual hallucinations.
Peduncular hallucinosis
Capgras delusion
Klazomania
Cotard delusion
Acholia
Fregoli delusion
Visual hallucinations in psychosis
Gemütlose psychopathy