Ocular abnormalities have apparent effects on brain activation. However, neuroimaging data about the ocular characteristics of healthy participants are still lacking to be compared with data for patients with ocular pathology. The objective of this multiple participants’ functional magnetic resonance imaging (fMRI) studies was to investigate the brain activation characteristics of healthy participants when they view stimuli of various shapes, pattern and size. During the fMRI scans, the participants view the growing ring, rotating wedge, fl ipping hour glass/bow tie, quadrant arc and full checker board stimuli. All stimuli have elements of black-and-white checkerboard pattern. Statistical parametric mapping (SPM) was used in generating brain activation via fi xed-effects (FFX) and conjunction analyses. The stimuli of various shapes, pattern and size produce different brain activation with more activation concentrated in the left hemisphere. These results are supported by the conjunction analysis which indicated that the left pre-central, post-central, superior temporal and occipital gyrus as well as the left cingulate cortices were involved when the participants viewed each given stimulus. Differential activation analysis showed activation with high specifi city in the occipital region due to the stimuli of various shapes, pattern and size. The activation in the right middle temporal gyrus was found to be signifi cantly higher in response to moving stimuli as compared to stationary stimuli. This confi rms the involvement of the right middle temporal gyrus in the observation of movements. The black-and-white checkerboard stimuli of various shapes, pattern and size, stationary and moving was found to 1) activate visual as well as other cortices in temporal and parietal lobes, 2) cause asymmetry in brain function and 3) exhibit functional integration characteristics in several brain areas.
Photic Stimulation

Glaukoma adalah sejenis penyakit neurodegeneratif yang berlaku akibat ketidakseimbangan dalam peredaran cecair akues yang disebabkan oleh resistan pada sistem pengaliran keluar cecair tersebut. Ini meningkatkan tekanan intraokular (TIO) yang menyebabkan kerosakan pada saraf optik dan seterusnya mengakibatkan kebutaan yang kekal. Oleh kerana TIO adalah satu faktor risiko glaukoma yang boleh dikawal, ciri-ciri dan variasi tekanan sepanjang 24 jam perlu dikenalpasti sebelum rawatan dimulakan. Pemantauan TIO adalah satu aspek yang terpenting dan kritikal dalam pengurusan glaukoma. Pelbagai tindakan kawalan melalui penggunaan teknologi yang berbeza telah dan sedang dilakukan untuk pemantauan TIO yang kerap dan berterusan selama 24 jam untuk menentukan kewujudan TIO yang tinggi (peak) dan fluktuasi tekanan. Artikel ini bertujuan untuk meninjau pendekatan inovatif yang terkini serta untuk mengulas kepentingan dan kelemahan setiap teknik bagi memperolehi profil TIO selama 24 jam.