Oculomotor disorders have been considered to be one of the negative symptoms in 
motor neuron disease (MND). However, recently, ophthalmoplegia, abnormal Bell's 
phenomenon and disturbance of pursuit movement have been reported. We tried to 
evaluate 32 patients with MND (19 males and 13 females; age, 35 to 77 years; 
52.4 +/- 10.1 years) by bedside examination and electro-oculography (EOG) using 
an eye tracking method. Twenty-three of them were classified as amyotrophic 
lateral sclerosis (ALS) and seven as bulbospinal muscular atrophy, and two were 
unclassified. One hundred healthy persons for bedside examination and twenty-two 
for EOG were investigated as controls. Findings by bedside examinations were as 
follows; 1) Slight limitations of upward only, up & downward and upward & 
horizontal gaze were observed in 5 cases (15.6%), 1 case (3.1%) and 1 case 
(3.1%), respectively. 2) Incomplete convergence was observed in 11 cases. 
(34.4%) 3) Horizontal gaze nystagmus was observed in 6 cases. (18.8%) 4) As 
regards the frequency of limitation of upward gaze and incomplete convergence, 
there were no statistically significant differences from those in controls. 
Electrooculographic results were: 1) square wave jerks (SWJs) were recorded in 3 
cases. (9.4%) 2) Amplitude ratio of saccade was significantly higher in MND than 
that in controls with the risk less than 0.1%. 3) The degree of ocular dysmetria 
was significantly higher in MND than that in controls with the risk less than 
0.5%. These abnormalities were not directly related to suffering period. 
Although the mechanism is not known, several reports of the effectiveness of 
thyrotropin releasing hormone (TRH) in ALS were recently published.(ABSTRACT 
TRUNCATED AT 250 WORDS)