Research of the Effect of Hyperthyroidism on Reaction Time Using the Oddball Paradigm

Aim: Thyroid hormones are so important for the normal physiological functions and the cognitive functions of brain. It is known that hyperthyroidism, the presence of excessive thyroid hormone produced by the thyroid gland, causes changes in cognitive functions. In this study, we have examined the effect of hyperthyroidism on motor response that result from this cognitive process by measuring reaction time to auditory stimuli. Material and Method: The study was conducted on newly diagnosed hyperthyroid patients (n=20) and healthy controls (n=20). The reaction time was evaluated in an auditory oddball paradigm. For that purpose, participants have been listened to 160 sound stimuli (120 standards, 40 targets). We asked them to press the button under their right hand when they hear the target sounds. The elapsed time between the presentation of the stimulus and the subsequent pressing button has been defined as reaction time. Results: Reaction time was significantly prolonged in the hyperthyroid group compared with the control group (p≤0.001). Conclusion: Hyperthyroid patients had prolonged perception time and significant decrease on attention and concentration. They can be result in prolonged reaction time because of impaired motor functions