Conduction Aphasia: Clinical Features and Management
Conduction aphasia is a specific type of language disorder characterized primarily by impaired repetition and frequent phonemic paraphasias (sound-based errors) despite relatively preserved comprehension and fluent spontaneous speech.
Clinical Features of Conduction Aphasia
Core Characteristics
- Impaired repetition: The hallmark feature, with particular difficulty repeating complex phrases and sentences
- Phonemic paraphasias: Sound-based errors in speech production (e.g., saying "poon" instead of "spoon")
- Frequent self-corrections: Patients often recognize their errors and attempt to correct them
- Preserved comprehension: Auditory and reading comprehension are relatively intact
- Fluent spontaneous speech: Speech remains grammatical and has normal prosody
Associated Features
- Word-finding difficulties: Patients may struggle to retrieve specific words 1
- Paraphrasing: Using circumlocutions to compensate for word retrieval problems
- Reduced verbal-auditory short-term memory: Present in nearly all cases 1
- Impaired phonological working memory: Difficulty maintaining phonological information 2
- Relatively intact visual object naming: Some patients may show preserved naming ability when viewing objects directly 3
Neuroanatomical Basis
- Primary lesion location: Left temporoparietal region, particularly the posterior temporal and inferior parietal lobes 1
- Specific area involvement: Area Spt (Sylvian parietal-temporal) in the posterior planum temporale 2
- Traditional view: Historically attributed to disconnection between Wernicke's and Broca's areas via the arcuate fasciculus
- Modern understanding: Now recognized as damage to a cortical sensory-motor integration area rather than just a white matter pathway 2
Assessment and Diagnosis
Patients with suspected conduction aphasia should be referred to a Speech-Language Pathologist (SLP) for comprehensive assessment of:
- Comprehension
- Speaking
- Reading
- Writing
- Gesturing
- Pragmatics
- Conversation 4
Treatment Approaches
Speech and Language Therapy
- Early intervention: Persons with aphasia should have early access to intensive language and communication therapy tailored to their needs, goals, and impairment severity 4
- Phonological training: Focus on improving phonological processing and segmentation 5
- Semantization: Strengthening semantic associations to support word retrieval 5
Specific Therapeutic Techniques
Production-focused therapy:
- Training on words, sentences, and discourse production
- Reading and writing exercises 4
Conversational treatment:
- Constraint-induced language therapy
- Communication partner training 4
Group therapy:
- Conversation groups guided by trained volunteers and caregivers
- Community-based aphasia groups 4
Technology-assisted therapy:
- Use of non-verbal strategies
- Assistive devices (e.g., iPads, tablets)
- Computerized language therapy to supplement other treatments 4
Prognosis
- Conduction aphasia may persist as a chronic language deficit in many patients 1
- However, good recovery is possible with appropriate rehabilitation, with some patients able to return to work 5, 6
- Prognosis appears better when cognitive functions outside of language remain intact 6
Clinical Considerations and Pitfalls
- Differential diagnosis: Distinguish from other fluent aphasias (e.g., Wernicke's aphasia) and motor speech disorders
- Cognitive assessment: Evaluate for associated deficits in verbal working memory
- Avoid overreliance on repetition tasks alone: Assessment should include comprehensive language evaluation
- Consider variant presentations: Some patients may show preserved visual naming despite impaired verbal repetition 3
- Monitor for progression: In rare cases, conduction aphasia can be the presenting symptom of primary progressive aphasia 6
Early identification and referral to speech-language therapy is essential for optimizing outcomes in patients with conduction aphasia.