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Aims The aim of this study was to assess the differences in saccadic latency (a measure of time delay experienced in eye movements) between alcohol-dependent and healthy controls. Materials and methods Participants Ninety-nine alcohol dependent patients were examined. Thirty-eight healthy controls were matched to the affected cohort according to demographic characteristics. Assessment In this study we used the Saccadometer Advanced System (Advanced Clinical Instrumentation, Cambridge, UK). The Saccadometer System allows quick and easy collection of saccadic responses within the shortest physiologically possible time (100 saccades in 5 min). The brevity of the testing routine minimizes any potential influence on the results due to fatigue in the test subjects. The eye movement measurements are automated and synchronised with stimuli presentation. This study analyzed saccadic latency and standard deviation of mean latency. Results There was higher saccadic latency and standard deviation of mean latency in alcohol-dependent individuals (224.43±56.24 msec) when compared to healthy controls (187.84±25.65 msec). A marked asymmetry of standard deviation of mean latency between right-sided and left-sided saccades was observed in the affected cohort. There was an increased standard deviation of right-sided saccades mean latency (69.96 msec) in alcohol-dependent individuals when compared to healthy controls (30.93 msec) and also an increased standard deviation of left-sided saccades mean latency (59.33 msec) when compared to healthy controls (33.09 msec). Conclusion It was found that alcohol dependence is associated with impaired (longer time delay) saccadic reaction.

Introduction There are abnormalities in eye movements in individuals with Alzheimer's disease, which are related to oculomotor frontal-subcortical circuit dysfunctions. Objectives and aims The aim of the study is to compare the parameters of saccadic eye movements in individuals with Alzheimer's disease with those in older adults without dementia. Methods 31 individuals with mild and intermediate Alzheimer's dementia (MMSE > 13) (26 women, mean age 76.8 ± 6.41 and 5 men, mean age 79.1 ± 5.21) and 30 individuals without symptoms of dementia (matched for age) were examined. The parameters of saccadic eye movements were measured with the use of Saccadometer Advanced. Two experiments were performed: Latency Trials (LAT) and Reflexive with Gap (RXG). Saccadic latency [ms], the reaction time [ms] and the number of executed saccades were measured. Results: LAT: Statistically significant differences in the number of saccades (α = 0.05, p = 0.000024) and in average latency [ms] (α = 0.05, p = 0.039) between the individuals with AD and the healthy ones were found. RXG: Statistically significant differences were found in all the variables tested: number of executed saccades (α = 0.05, p = 0.0265), average latency [ms] (α = 0.05, p = 0.043) and average duration [ms] (α = 0.05, p = 0.000035) between persons from the control group and those from the experimental group. Conclusions It was found that the level of oculomotor efficiency in mild and intermediate Alzheimer's disease is significantly lower in relation to older people without dementia.

We compared horizontal saccadic eye movements in patients with dementia (n=18), and age-matched patients with major depression (n=18) or healthy controls (n=18). Cognitive functions were evaluated using Mini-Mental-State-Examination (MMSE) and ADAS-cog.Results:Saccadic latency and number of saccadic intrusions were significantly (p< 0.001) higher in patients with dementia relative to healthy controls and depressed patients. There were significant correlations between MMSE total score and latency (r = -0.78, p< 0.01) or number of saccadic intrusions (r = -0.80, p< 0.001) in the demential group. In addition, both saccadic parameters were significantly associated with ADAS-cog total score of patients with dementia, whereas the subscale “orientation” showed the strongest correlation with latency (r = 0.71, p< 0.01) and intrusions (r = 0.74, p< 0.01).There were no significant differences in saccadic eye movements between healthy controls and patients with major depression as a whole, or a subgroup of depressed patients with the worst cognitive performance (n=9).Conclusions:It seems that disturbances in horizontal saccadic eye movements in patients with dementia are related to the degree of cognitive deficits in these patients. On the other hand, the lack of alterations in horizontal saccadic eye movements in depressed patients despite poor cognitive performance indicates different mechanism.