Aphasia following right thalamic hemorrhage in a dextral

Area of Science:

• Neuroscience
• Neurolinguistics
• Clinical Neurology

Background:

• Thalamic hemorrhage is a rare cause of aphasia, typically associated with left hemisphere lesions.
• Right thalamic lesions are infrequently studied for their impact on language processing.

Observation:

• A 74-year-old woman with a right thalamic hemorrhage presented with acute aphasia, characterized by reduced spontaneous speech, fluent output with paraphasia, anomia, and mild comprehension deficits.
• Repetition abilities remained intact during the acute phase.
• Language deficits were assessed over a 1-year period through sequential neurologic examinations and aphasia testing.

Findings:

• The patient's aphasia evolved over one year, with significant recovery in most language domains.
• Object naming emerged as the primary persistent language deficit at the 1-year mark.
• This case represents the first documented instance of right thalamic involvement affecting speech and language in an individual without a history of left-handedness.

Implications:

• Right thalamic lesions can indeed cause significant aphasia, challenging the traditional view of left-hemisphere dominance for language.
• The distinct recovery pattern highlights the complex role of subcortical structures, like the thalamus, in language function.
• Further research into subcortical aphasia is warranted to refine our understanding of brain-language relationships.