Visual extinction: Difference between revisions

Latest revision as of 10:53, 15 February 2025

A neurological condition affecting visual perception

Visual extinction is a neurological condition characterized by the inability to perceive a stimulus in one visual field when a simultaneous stimulus is presented in the opposite visual field. This phenomenon is often observed in patients with damage to the parietal lobe of the brain, particularly following a stroke.

Pathophysiology[edit]

Visual extinction is typically associated with lesions in the right hemisphere of the brain, which is responsible for attention and spatial awareness. The condition is thought to arise from a deficit in the brain's ability to process and integrate visual information from both visual fields simultaneously. When two stimuli are presented, the brain fails to attend to the stimulus in the affected visual field, leading to extinction.

Clinical Presentation[edit]

Patients with visual extinction may not be aware of the deficit, as it only becomes apparent when both visual fields are stimulated simultaneously. In clinical settings, this is often tested using a technique called "double simultaneous stimulation," where the patient is asked to report stimuli presented to both sides of their visual field.

Diagnosis[edit]

The diagnosis of visual extinction is primarily clinical, based on the patient's history and neurological examination. Neuroimaging techniques such as MRI or CT scan may be used to identify lesions in the brain that could be responsible for the condition.

Management[edit]

There is no specific treatment for visual extinction, but rehabilitation strategies may help improve the condition. These strategies often focus on retraining the brain to attend to stimuli in the affected visual field. Occupational therapy and visual scanning exercises are commonly used.

Prognosis[edit]

The prognosis for visual extinction varies depending on the underlying cause and the extent of brain damage. Some patients may experience improvement over time, especially with rehabilitation, while others may have persistent deficits.

Related pages[edit]

Diagram of the visual pathways in the brain, showing areas that may be affected in visual extinction.

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-'''Visual extinction''' is a [[neurological disorder]] that occurs when a person is unable to perceive a stimulus in the presence of another stimulus. This condition is often associated with [[stroke]]s and [[brain injury]].
+{{Short description|A neurological condition affecting visual perception}}
-== Overview ==
+'''Visual extinction''' is a neurological condition characterized by the inability to perceive a stimulus in one visual field when a simultaneous stimulus is presented in the opposite visual field. This phenomenon is often observed in patients with damage to the [[parietal lobe]] of the brain, particularly following a [[stroke]].
-Visual extinction is a phenomenon that occurs when a person is unable to perceive a stimulus in the presence of another stimulus. This is often seen in patients who have suffered a [[stroke]] or a [[brain injury]]. The person may be able to perceive each stimulus individually, but when they are presented together, the person may only be able to perceive one of them.
+==Pathophysiology==
+Visual extinction is typically associated with lesions in the [[right hemisphere]] of the brain, which is responsible for attention and spatial awareness. The condition is thought to arise from a deficit in the brain's ability to process and integrate visual information from both visual fields simultaneously. When two stimuli are presented, the brain fails to attend to the stimulus in the affected visual field, leading to extinction.
-== Causes ==
+==Clinical Presentation==
+Patients with visual extinction may not be aware of the deficit, as it only becomes apparent when both visual fields are stimulated simultaneously. In clinical settings, this is often tested using a technique called "double simultaneous stimulation," where the patient is asked to report stimuli presented to both sides of their visual field.
-Visual extinction is often caused by damage to the [[parietal lobe]] of the brain. This can occur as a result of a stroke or a brain injury. The parietal lobe is responsible for processing sensory information, including visual stimuli. When this area of the brain is damaged, it can lead to a variety of sensory deficits, including visual extinction.
+==Diagnosis==
+The diagnosis of visual extinction is primarily clinical, based on the patient's history and neurological examination. Neuroimaging techniques such as [[MRI]] or [[CT scan]] may be used to identify lesions in the brain that could be responsible for the condition.
-== Symptoms ==
+==Management==
+There is no specific treatment for visual extinction, but rehabilitation strategies may help improve the condition. These strategies often focus on retraining the brain to attend to stimuli in the affected visual field. Occupational therapy and visual scanning exercises are commonly used.
-The main symptom of visual extinction is the inability to perceive a stimulus when it is presented alongside another stimulus. This can occur in any sensory modality, but it is most commonly seen in the visual domain. For example, a person with visual extinction may be able to see a car on the left side of the road, but if a car is also present on the right side of the road, they may only be able to perceive the car on the left.
+==Prognosis==
+The prognosis for visual extinction varies depending on the underlying cause and the extent of brain damage. Some patients may experience improvement over time, especially with rehabilitation, while others may have persistent deficits.
-== Diagnosis ==
+==Related pages==
+* [[Parietal lobe]]
+* [[Stroke]]
+* [[Visual field]]
+* [[Hemineglect]]
-Diagnosis of visual extinction is typically made through a series of neurological tests. These tests may include visual field testing, in which the person's field of vision is tested to determine if there are any areas where they cannot perceive visual stimuli. Other tests may include sensory testing, in which the person's ability to perceive different types of sensory stimuli is tested.
+[[File:Gray1197.png|thumb|right|Diagram of the visual pathways in the brain, showing areas that may be affected in visual extinction.]]
-== Treatment ==
+[[Category:Neurology]]
-Treatment for visual extinction typically involves [[rehabilitation therapy]]. This may include visual training exercises to help the person improve their ability to perceive multiple stimuli at once. In some cases, medication may also be used to help manage the symptoms of visual extinction.
-== See also ==
-* [[Neglect syndrome]]
-* [[Hemianopsia]]
-* [[Agnosia]]
-[[Category:Neurological disorders]]
 [[Category:Visual perception]]
-[[Category:Stroke]]
-[[Category:Brain injury]]
-{{stub}}