Relationship between exploratory eye movement, P300, and reaction time in schizophrenia

Abstract

Aims: Exploratory eye movement (EEM), P300 and reaction time (RT) tests may relate to the important parts of information processing in the human brain. Therefore the aim of the present study was to compare EEM, P300 and RT test data in schizophrenic and normal control groups to investigate whether schizophrenic patients have information processing abnormalities. In addition, the potential correspondence between the three tests was examined in order to investigate the information processing dysfunctions seen in schizophrenic patients. Methods:The EEM, P300 and RT performances were recorded in 34 schizophrenic and 36 normal control subjects. Ten parameters were measured: four from the EEM test (number of eye fixations, total eye scanning length, cognitive search score and responsive search score [RSS]); two from the P300 test (amplitude and latency); and four from the RT test (simple reaction time, index of reaction time crossover [IRTcrossover], set index and coefficient of variation).Results: These parameters in the schizophrenic patients differed significantly from those in the control group. Additionally, there was a significant correlation between the RSS and the IRT-crossover in the schizophrenic patients. Conclusion:The present group comparisons (schizophrenia vs normal controls) are consistent with previous studies in that the abnormalities in EEM, P300 and RT tests in schizophrenic patients were able to be replicated. Moreover, based on the former psychological theory, it is reasonable to propose that the RSS is associated with the IRT-crossover. The present results may contribute to elucidation of the pathophysiological signature of schizophrenia.

Olfactory Dysfunction in Adults from Rio Grande do Norte: A Cross-Sectional Study

“…This potential is mainly related to cognitive functions and attention, but it is related to hearing, smell, eye movements and other functions, and may, in the future, be used to access olfactory function. [18][19][20][21] As for the test result, a higher relative frequency of altered smell (41.11%) was observed than other studies that also used the CCCRC. Toledano et al 22 found a frequency of 11% in a Spanish sample (n ¼ 100), and Veyseller et al 23 This different result may be related to several factors.…”

“…This potential is mainly related to cognitive functions and attention, but it is related to hearing, smell, eye movements and other functions, and may, in the future, be used to access olfactory function. 18 19 20 21 …”

Neurocognitive Functions in Patients With Remitted and Nonremitted Schizophrenia: A Cross-Sectional Study

“…An exploratory eye movement (EEM) study examining spatial perception showed that spatial perception was worse in patients with schizophrenia than in healthy individuals (Takahashi, Tanabe, Sakai, et al, 2008). Both patients with schizophrenia and their siblings without schizophrenia demonstrated decreased EEM (Takahashi, Tanabe, Yara, et al, 2008), and EEM parameters can distinguish people with schizophrenia from those with other mental disorders (Suzuki et al, 2009).…”

P300 as an auxiliary method in clinical practice: A review of literature

“…Some studies indicated changes in P300 characteristics in patients with Parkinson's disease (the changes correlated with the degree of the disease determined according to the Hoehn and Yahr scale), growth hormone deficiency, Huntington's disease, Tourette syndrome, and narcolepsy (2,9,(24)(25)(26)(27). Changes of P300 characteristics, lowered amplitude, and extended latency have also been noticed in schizophrenia (28)(29)(30)(31)(32)(33)(34)(35)(36), post-traumatic stress disorder (36,37,40), endogenous psychoses (38)(39)(40)(41), panic disorder (42)(43)(44)(45), and depressive patients (46,47). Additionally, a few papers described changes of P300 in impulsive aggressive criminals and obsessive-compulsive disorder (48,49).…”