What is the likely location of the issue in a patient with expressive aphasia and motor symptoms on the right side, specifically in the cerebral cortex or putamen (part of the basal ganglia)?

From the Guidelines

The patient's presentation of right-sided motor symptoms combined with expressive aphasia most likely indicates damage to the left cerebral cortex, specifically Broca's area. Expressive aphasia (also called Broca's aphasia) is characterized by difficulty producing speech while comprehension remains relatively intact, and is caused by damage to the inferior frontal gyrus of the dominant hemisphere (typically left) 1. This area is located in the cerebral cortex, not the putamen. The putamen is part of the basal ganglia and while damage there can cause motor symptoms, it would not typically cause aphasia, which is a higher cortical function.

Key Points to Consider

• The left cerebral cortex, specifically Broca's area, is responsible for expressive aphasia, which is characterized by difficulty producing speech while comprehension remains relatively intact 1.
• Damage to the putamen, part of the basal ganglia, can cause motor symptoms but would not typically cause aphasia, which is a higher cortical function.
• The left-sided cortical lesion explains both the language deficit and the contralateral (right-sided) motor symptoms due to the crossing of motor pathways in the brain.
• Studies have shown that lesion location and aphasia symptoms are related, and that functional MRI activity in the early subacute phase can predict long-term recovery 1.
• The use of structural MRI and functional brain assessments, such as fMRI, can provide insights into the neural basis of language deficits and predict outcome, but larger studies are required to validate this approach 1.

Clinical Implications

• The diagnosis of expressive aphasia should prompt a thorough evaluation of the patient's language abilities and cognitive function.
• Imaging studies, such as MRI, should be used to identify the location and extent of the lesion.
• Rehabilitation efforts should focus on improving language function and addressing any related cognitive deficits.
• The patient's prognosis and potential for recovery should be discussed with the patient and their family, taking into account the location and extent of the lesion, as well as the patient's overall health and cognitive function.

From the Research

Location of the Issue in Expressive Aphasia

The likely location of the issue in a patient with expressive aphasia and motor symptoms on the right side can be related to the cerebral cortex or putamen (part of the basal ganglia).

• The study 2 suggests that aphasia is highly correlated with a predominant right-sided movement disorder, indicating the involvement of the left hemisphere.
• Research 3, 4 indicates that lesions in the left frontal lobe, specifically in the Broca's area, can cause different types of aphasia, including Broca's aphasia and Broca area's aphasia.
• The left frontal lobe is responsible for language production, and damage to this area can result in expressive aphasia, characterized by difficulty speaking in grammatically complete sentences, finding the right words, and articulating words correctly.
• The putamen, part of the basal ganglia, is involved in motor control and can contribute to motor symptoms on the right side, as seen in corticobasal syndrome 2.
• The study 5 highlights the importance of clinical profiling in diagnosing and treating anomic aphasia, which can also present with word-finding difficulties and right-sided motor symptoms.

Cerebral Cortex Involvement

• The left frontal lobe, particularly the Broca's area, is a critical region for language production and is often implicated in expressive aphasia 3, 4.
• Damage to this area can result in a range of language deficits, including difficulty with speech articulation, word retrieval, and sentence construction.
• The study 2 suggests that the left hemisphere is involved in the presentation of aphasia with right-sided motor symptoms, pointing to the importance of the cerebral cortex in language processing.

Basal Ganglia Involvement

• The putamen, part of the basal ganglia, plays a role in motor control and can contribute to motor symptoms on the right side, as seen in corticobasal syndrome 2.
• The basal ganglia are also involved in language processing, particularly in the regulation of speech articulation and fluency.
• However, the study 2 suggests that the basal ganglia may not be the primary location of the issue in expressive aphasia with right-sided motor symptoms, as the correlation between aphasia and right-sided motor symptoms is more strongly associated with left hemisphere involvement.