Logopenic progressive aphasia
Logopenic progressive aphasia (LPA) is a variant of primary progressive aphasia.[1] It is defined clinically by impairments in naming and sentence repetition.[2] It is similar to conduction aphasia and is associated with atrophy to the left posterior temporal cortex and inferior parietal lobule. It is suspected that an atypical form of Alzheimer's disease is the most common cause of logopenic progressive aphasia.[3][4]
Although patients with the logopenic variant of PPA are still able to produce speech, their speech rate may be significantly slowed due to word retrieval difficulty.[4] Over time, they may experience the inability to retain lengthy information, causing problems with understanding complex verbal information.[5] Some additional behavioral features include irritability, anxiety and agitation.[3]
Compared to other subtypes of primary progressive aphasia, the logopenic variant has been found to be associated with cognitive and behavioral characteristics. Studies have shown that patients with the logopenic variant perform significantly worse on tests of calculation than other primary progressive aphasia patients. Several logopenic variant patients, especially those with Alzheimer's disease pathology, have also been found to perform poorly on memory tasks.[3]
Logopenic progressive aphasia is caused by damage to segregated brain regions, specifically the inferior parietal lobe and superior temporal regions. Difficulties in naming are produced from the thinning of the inferior parietal lobe. Damage to the dorsal pathways creates language deficiency in patients that is characteristic of logopenic progressive aphasia.[2]
References
- Harciarek M, Kertesz A (September 2011). "Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship". Neuropsychol Rev. 21 (3): 271–87. doi:10.1007/s11065-011-9175-9. PMC 3158975. PMID 21809067.
- Leyton CE, Piguet O, Savage S, Burrell J, Hodges JR (2012). "The neural basis of logopenic progressive aphasia". J. Alzheimer's Dis. 32 (4): 1051–9. doi:10.3233/JAD-2012-121042. PMID 22890099.
- Henry ML, Gorno-Tempini ML (December 2010). "The logopenic variant of primary progressive aphasia". Curr. Opin. Neurol. 23 (6): 633–7. doi:10.1097/WCO.0b013e32833fb93e. PMC 3201824. PMID 20852419.
- Gorno-Tempini ML, Hillis AE, Weintraub S, et al. (March 2011). "Classification of primary progressive aphasia and its variants". Neurology. 76 (11): 1006–14. doi:10.1212/WNL.0b013e31821103e6. PMC 3059138. PMID 21325651.
- UCSF Memory and Aging Center. (2011, February 22). SF: The Regents of the University of California. Retrieved December 5, 2011 from http://memory.ucsf.edu/education/diseases/ppa
Further reading
- Harciarek M, Kertesz A (September 2011). "Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship". Neuropsychol Rev. 21 (3): 271–87. doi:10.1007/s11065-011-9175-9. PMC 3158975. PMID 21809067.
- Gorno-Tempini ML, Dronkers NF, Rankin KP, et al. (March 2004). "Cognition and anatomy in three variants of primary progressive aphasia". Ann. Neurol. 55 (3): 335–46. doi:10.1002/ana.10825. PMC 2362399. PMID 14991811.
- Rohrer JD, Knight WD, Warren JE, Fox NC, Rossor MN, Warren JD (January 2008). "Word-finding difficulty: a clinical analysis of the progressive aphasias". Brain. 131 (Pt 1): 8–38. doi:10.1093/brain/awm251. PMC 2373641. PMID 17947337.