Saccadic eye movement disturbances in whiplash patients with persistent complaints

• Published in: Brain (London, England : 1878) Vol. 123; no. 4; pp. 828 - 835
• Main Authors: Mosimann, U. P., Müri, R. M., Felblinger, J., Radanov, B. P.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.04.2000; Oxford Publishing Limited (England)
• Subjects: Adult; BDI = Beck Depression Inventory; Biological and medical sciences; cortex; DSM-IV = Diagnostic and Statistical Manual of Mental Disorders; Emotions; eye movement disturbance; F = central fixation point; Female; Humans; Injuries of the limb. Injuries of the spine; Male; Medical sciences; Middle Aged; Motivation; PEA = percentage error in amplitude; Reaction Time; Recovery of Function; Reflex; Saccades; T = amplitude of the visual target; Traumas. Diseases due to physical agents; Whiplash Injuries - physiopathology; Whiplash Injuries - psychology; whiplash injury; Human; Eye disease; Diseases of the osteoarticular system; Complication; Exploration; Spine disease; Oculomotor syndrome; Trauma; Cervical spine; Saccadic eye movement
• ISSN: 0006-8950; 1460-2156; 1460-2156
• DOI: 10.1093/brain/123.4.828

In order to analyse the possible basis of subjective complaints following whiplash injury, horizontal eye movements were examined in subjects with persistent complaints (`symptomatic group') and subjects who had completely recovered (`recovered group'). The results for the symptomatic and recovered groups were compared with those for age-matched, healthy volunteers (control group). A battery of different saccade paradigms was employed: two were reflexive saccade tasks including a gap and an overlap task, and two were intentional saccade tasks consisting of an antisaccade and a memory-guided saccade task. In addition, the symptomatic and recovered groups also underwent psychiatric evaluation in a structured clinical interview, and all groups were assessed for emotional functioning using the Beck Depression Inventory (BDI). The recovered group did not differ significantly from the control group in saccade performance and emotional functioning. The symptomatic group showed dissociation of their performances of reflexive and intentional saccade tasks: performance in reflexive saccade tasks was normal, but in intentional saccade tasks the symptomatic group showed significantly impaired inhibition of unwanted reflexive saccades, impaired saccade triggering (i.e. increased latency) and a higher percentage error in amplitude in memory-guided saccades. Based on clinical interviews, no signs of major depression or dysthymia were found in any of the groups. Compared with the other two groups, the symptomatic group had significantly higher overall BDI scores, but these resulted from BDI dimensions that were non-specific to depression, viz. `physiological manifestations' (e.g. fatigue, sleep disturbance) or `performance difficulty' (e.g. work inhibition). In summary, in the symptomatic group the pattern of eye movement disturbances together with normal performance in reflexive saccade tasks and impaired performance in the intentional saccade tasks, especially impaired inhibitory function, suggests dysfunction of prefrontal and frontal cortical structures.