What are the different types of aphasia?

Types of Aphasia

Aphasia is classified into several distinct types based on the pattern of language impairment, with the major categories being fluent versus non-fluent aphasia, and specific syndromes including Broca's aphasia, Wernicke's aphasia, transcortical aphasias, and in neurodegenerative contexts, the three variants of primary progressive aphasia (semantic, non-fluent/agrammatic, and logopenic). 1, 2

Classical Stroke-Related Aphasia Syndromes

Broca's Aphasia (Non-Fluent Aphasia)

• Characterized by impaired speech production with relatively preserved comprehension 3
• Associated with posterior inferior frontal lesions, though persistent deficits involve additional central and subcortical components 4
• Patients struggle with word retrieval, grammatical structure (agrammatism), and effortful speech output 2, 3
• Often co-occurs with apraxia of speech, which is a distinct motor planning disorder that should not be confused with the aphasia itself 1, 3

Wernicke's Aphasia (Fluent Aphasia)

• Fluent speech output with significant comprehension deficits 4
• Requires a superior posterior temporal lesion for diagnosis 4
• Patients may produce jargon speech (meaningless or nonsensical words) while remaining unaware of their errors 4, 5
• Persistent jargon aphasia specifically associates with supramarginal gyrus lesions 4

Transcortical Motor Aphasia

• Involves lesions of the supplementary speech area 4
• Characterized by reduced spontaneous speech with preserved repetition abilities 4

Transcortical Sensory Aphasia

• Related to lesions in the watershed area between middle cerebral and posterior cerebral arteries 4
• Features impaired comprehension with preserved repetition 4

Primary Progressive Aphasia (PPA) Variants

Semantic Variant (svPPA)

• Associated with frontotemporal lobar degeneration pathology (TDP-43 type C) 1, 2
• Characterized by difficulties in word retrieval and understanding word meaning 1, 2
• Patients lose knowledge of what words mean while maintaining fluent speech output 2

Non-Fluent/Agrammatic Variant (nfvPPA)

• Generally associated with frontotemporal lobar degeneration (tauopathy) 1, 2
• Features apraxia of speech and/or agrammatism (grammatical difficulties) 1, 2, 3
• Speech is effortful, halting, and grammatically simplified 2, 3

Logopenic Variant (lvPPA)

• Commonly associated with Alzheimer's disease pathology 1, 2
• Characterized by word-finding difficulties with preserved word meaning but impaired phonological working memory 1, 2, 3
• Patients struggle to retrieve words but understand their meanings when provided 2, 3

Key Clinical Distinctions

Fluency as a Distinguishing Feature

• Fluent aphasias (Wernicke's, transcortical sensory, semantic variant PPA) produce speech easily but with content or comprehension problems 4, 2
• Non-fluent aphasias (Broca's, transcortical motor, non-fluent/agrammatic PPA) have effortful, reduced speech output 4, 2

Comprehension Patterns

• Comprehension is severely impaired in Wernicke's aphasia and semantic variant PPA 4, 2
• Comprehension is relatively preserved in Broca's aphasia and non-fluent/agrammatic PPA 3, 4
• Logopenic variant shows specific deficits in phonological working memory rather than semantic comprehension 2, 3

Assessment Domains

All aphasia evaluations must assess multiple language domains: 1

• Spontaneous speech production 6
• Auditory comprehension 6
• Naming ability 6
• Repetition 6
• Reading comprehension 6
• Written expression 6

Common Pitfall

Do not confuse anomia (isolated word-finding difficulty) with expressive aphasia—anomia alone without agrammatism and non-fluency represents a different clinical entity 3. Similarly, apraxia of speech is a motor planning disorder that typically co-occurs with non-fluent aphasia but represents a distinct phenomenon 1, 3.