Visual agnosia is an impairment in recognition of visually presented objects. It is not due to a deficit in vision (acuity, visual field, and scanning), language, memory, or intellect. While cortical blindness results from lesions to primary visual cortex, visual agnosia is often due to damage to more anterior cortex such as the posterior occipital and/or temporal lobe(s) in the brain. [2] There are two types of visual agnosia: apperceptive agnosia and associative agnosia. Recognition of visual objects occurs at two primary levels. At an apperceptive level, the features of the visual information from the retina are put together to form a perceptual representation of an object. At an associative level, the meaning of an object is attached to the perceptual representation and the object is identified. If a person is unable to recognize objects because they cannot perceive correct forms of the objects, although their knowledge of the objects is intact (i.e. they do not have anomia), they have apperceptive agnosia. If a person correctly perceives the forms and has knowledge of the objects, but cannot identify the objects, they have associative agnosia. Symptoms and signs
While most cases of visual agnosia are seen in older adults who have experienced extensive brain damage, there are also cases of young children with less brain damage during developmental years acquiring the symptoms.
It can be found in the context of schizophrenia and delusional disorder, such as bipolar disorder, but is also associated with alcoholism and sexual dysfunction and has been reported after neurological illness (i.e. Parkinsons). The name "Othello Syndrome" comes from the character in Shakespeares play Othello, who murders his wife as a result of a false belief that she has been unfaithful. Recently, some psychologists and psychiatrists have asserted that Othello was deceived rather than deluded about Desdemonas alleged infidelity and thus did not have ‘the Othello Syndrome’. Psychiatric history
Presenting difficulties: neurotic or psychotic jealousy
Past psychiatric history: neurotic or psychotic disorders, deliberate self-harm and attempted suicide
Family history: mental illness including pathological jealousy
Relationship history: incorporating both the current and previous relationship and taking account of the quality of the relationships and the difficulties experienced
Forensic history: previous and pending charges and convictions as well as deviant behavior which was not reported or did not result in a charge or conviction (including aggressive behavior and stalking)
Medical history: organic causes which may be responsible for the morbid jealousy (i.e. Parkinsons)

Forms
Obsessions: the individuals own thoughts are egodystonic; they are acknowledged to be senseless, and usually resisted. Jealous thoughts are experienced as intrusive and excessive, and compulsive behavior such as checking up on their partner may follow. Egodystonicity (the distress caused by thoughts that are unwanted and viewed as contrary to conscious wishes) generally varies a large amount between patients and “a continuum from obsessional to delusional, which morbid jealousy has been suggested” (Insel & Akiskal 1986).