ABSTRACT
Introduction: The rate at which a successive light stimulusappears to be steady and continuous is called as the criticalflickering fusion frequency (CFFF). It is expressed in Hzand is referred to as the threshold frequency. It providesthe information about CNS activity and arousal as well asmeasures the discrete sensory events happening in the centralnervous system. To perceive the flickering light eye and brainhave to work simultaneously and have to act together. TheCFFFR was measured using critical flicker fusion apparatus.The study aimed to measure critical flicker fusion frequencyand to measure the effect of age, gender, sleep and displayscreens on critical flicker fusion frequencyMaterial and methods: The study was done in the departmentof Physiology, Maharishi Markandeshwar Medical Collegeand hospital, Solan, HP after taking institutional ethicalcommittee clearance. A total of 1000 apparently healthysubjects were recruited from the institute which included thestudents, faculty, non teaching staff and nursing staff. Criticalflicker fusion frequency was measured using Flicker Fusionapparatus (FF-705): Medicaid Ambala.The critical flickerfusion frequency threshold was noted after explaining theprocedure in their native language and obtaining consent. Thedata collected was analyzed stastically.Results: We found a significant difference in the values ofCFFFR between the younger age group and among the olderage group. CFFFR and age are indirectly proportional toeach other with increase in age there is decrease in the valueof CFFFR. The value of CFFFR was found to be higher inindividuals with a normal sleep pattern and duration comparedto those having less sleeping hours Inadequate sleep also hasbeen shown to decrease the motor functioning, decreasedlearning ability, poor productivity and shortened memory.CFFFR was higher in individuals playing games compared tothose who were using display screens normally, in addition toit those individuals who were playing instructive games had ahigher CFFRT than those playing quest games.Conclusion: In this study we measured the critical flickerfusion and the factors that have a role in increasing ordecreasing the CFFFR threshold. A simple and non invasiveprocedure helps in finding the harmful effects of variousfactors like age gender sleep disturbances or over usage ofdisplay screens on retina and central nervous system.
ABSTRACT
Introduction: The photostress recovery test (PSRT), dependson resynthesis of visual pigments and measures the time torecover after bleaching due to light exposure. Abnormalrecovery times in retinal diseases or toxicity suggests thatthe pathology in these conditions involves the outer layerof the retina or the pigment epithelium. Aim: 1) To measurephotostress recovery time in chronic alcoholics males; (2)To measure photostress recovery time in apparently healthymales; (3) To compare photostress recovery time in apparentlyhealthy males and chronic healthy malesMaterial and methods: Photostress recovery time wasrecorded using Photostress Recovery Tester (GT – 991Medicaid: Chandigarh). The subject was presented with ahigh beam of light focused on the eyes of subjects for shortand fixed period of time. As soon as light stimulation wasover, a word was displayed on screen for subject to read andautomatically the clock started counting in seconds. Whenthe subject recognized the word displayed he pressed the stopbutton on the remote control and read it out aloud, the clockstopped counting and word disappeared.Result: The p-value was statistically significant with a valueof 0.003 showing a comparable difference of PSRT in groupI and group II.Conclusion: Alcohol predisposes nervous tissue to injury viamultiple mechanisms, including the development of oxidativestress. Retina is another among the vulnerable area for redoxchanges caused due alcohol intoxication, with lower thresholdlevels of ethanol tolerance.