Gerstmann Syndrome: The Inability To Recognize Fingers

Gerstmann syndrome is a rare neurological disorder. It is known for its most prominent feature: the patient’s inability to recognize their own fingers. However, far beyond this symptom, it is a much more complex and acquired disease – the set of symptoms appears after an injury.

Its name comes from Josef Gerstmann, a young assistant in the Department of Neurology at the University of Vienna, Austria. This student described a set of symptoms in a woman who had suffered a stroke. From then on, the disease composed of agraphia, digital agnosia and acalculia took its name.

The Causes of Gerstmann Syndrome

First, it should be noted that most reported cases arise from a vascular problem. This seems to be the main cause of a syndrome that is characterized by the dissolution of the morphological knowledge of the hands and the inability to work with them. The symptoms can be summarized, then, in:

• Digital Agnosia. Impossible to recognize fingers. The patient acts as if he doesn’t count on his fingers, as if he doesn’t have them.
• Agraphia. Together with the previous symptom, the patient loses the ability to express himself through writing.
• Calculate. Gerstmann syndrome patients also lose the ability to perform simple arithmetic operations.
• Disorientation. Inability to orient oneself correctly in space, confusing or not recognizing the difference between left and right.

The damage acquired

In 1930, Gerstmann described the syndrome by studying the lesions of his patients. He found that most had damage to the dominant parietal lobe, specifically the angular gyrus.

In the parietal lobe is the Penfield homunculus, a somatosensory mapping of the body. Within the parietal lobe there is a specific region focused on the fingers.

This area is much larger in proportion to the rest of the body, due to the importance and amount of nerve endings our hands have.

the angular turn

This area especially damaged in Gerstmann syndrome occupies a posterior portion of the parietal lobe. It is related to the interpretation of language, the designation of a common code for visual and auditory information.

In general, patients with this syndrome have a stroke in the left middle cerebral artery, which supplies the angular gyrus.

Clinical features

It should be clarified that Gerstmann syndrome usually presents incompletely. This means that the top three symptoms do not necessarily need to be present to make the diagnosis.

On many occasions, there is no agraphia, and semantic aphasia is common in its place , a defect in the understanding of logical-grammatical structures.

Gerstmann’s syndrome today

Since this syndrome was described a long time ago, the advancement of science has made many of its characteristics put to the test. There are currently discussions about the organic basis of the syndrome, proposing other areas of the parietal lobe in its etiology.

Most patients have lesions in the left parietal lobe, the dominant hemisphere in the majority of the right-handed population. Anomalies occur at the cortical level, that is, in areas of complex processing.

Diagnosis of Gerstmann’s Syndrome

The main disciplines that are responsible for addressing the diagnosis of this syndrome are neurology and neuropsychology. Suspicions are often evident when proposing tasks that involve finger recognition.

For neurology, the diagnosis begins with exploratory exams and is confirmed through tomography and magnetic resonance that allow to visualize the damaged tissue. Furthermore, neuropsychology is responsible for assessing and analyzing impaired cognitive abilities through clinical observation.

Gerstmann syndrome treatment

Treatments are also divided and differentiated depending on the responsible specialist. In short, a combined approach between neurology and psychology is always needed.

• Neurological treatment. The approach is based on treating organic damage through standardized procedures. Treatment will depend on whether the cause was vascular or related to a brain tumor.
• Neuropsychological treatment. This approach is based on working the cognitive functions affected by the injury. Furthermore, given the variability of symptoms, treatment should be individualized and multidisciplinary.
• Psychoeducation. Information and awareness about the syndrome are very important to work on the underlying emotional aspects.

Finally, both treatments must be focused on the patient’s functional recovery, with goals that seek optimal functioning and discourage isolation.

At first, despite the fact that Gerstmann syndrome is rare in the population, it attracted the attention of researchers and specialists due to its characteristics.

The interest lies in the fact that the correct functioning of the brain also depends on correct vascular functioning. Therefore, all activities that are a risk factor for the circulatory system are also a danger for the nervous system.