Graefes Arch Clin Exp Ophthalmol. 2013 Aug 6. [Epub ahead of print]
Characterising eye movement dysfunction in myalgic encephalomyelitis/chronic fatigue syndrome.
Source
School of Psychology, College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester, UK, s.p.badham@warwick.ac.uk.
Abstract
BACKGROUND:
People who suffer from myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) often report that their eye movements are sluggish and that they have difficulties tracking moving objects. However, descriptions of these visual problems are based solely on patients' self-reports of their subjective visual experiences, and there is a distinct lack of empirical evidence to objectively verify their claims. This paper presents the first experimental research to objectively examine eye movements in those suffering from ME/CFS.
METHODS:
Patients were assessed for ME/CFS symptoms and were compared to age, gender, and education matched controls for their ability to generate saccades and smooth pursuit eye movements.
RESULTS:
Patients and controls exhibited similar error rates and saccade latencies (response times) on prosaccade and antisaccade tasks. Patients showed relatively intact ability to accurately fixate the target (prosaccades), but were impaired when required to focus accurately in a specific position opposite the target (antisaccades). Patients were most markedly impaired when required to direct their gaze as closely as possible to a smoothly moving target (smooth pursuit).
CONCLUSIONS:
It is hypothesised that the effects of ME/CFS can be overcome briefly for completion of saccades, but that continuous pursuit activity (accurately tracking a moving object), even for a short time period, highlights dysfunctional eye movement behaviour in ME/CFS patients. Future smooth pursuit research may elucidate and improve diagnosis of ME/CFS.
- PMID:
- 23918092
- [PubMed - as supplied by publisher]
It might be interesting to note here, that I recently learned that the eye control muscles have among the highest concentrations of mitochondria. This could lend weight to the mitochondrial insufficiency model of ME: the fine motor control necessary to keep the eyes operating effectively, would likely be one of the first signs of a mitochondrial problem.
ReplyDeleteIt might be interesting to note here, that I recently learned that the eye control muscles have among the highest concentrations of mitochondria. This could lend weight to the mitochondrial insufficiency model of ME: the fine motor control necessary to keep the eyes operating effectively, would likely be one of the first signs of a mitochondrial problem.
ReplyDeleteThanks for finding this, and for anonymous' interesting comment. There is so much progress being made, and so sad it takes so long, if ever, for these small research findings to be replicated for ME/CFS.
ReplyDeleteFor the record, my ME/CFS husband has certainly been reporting odd symptoms that could line up nicely with this finding.