It has been suggested that infants resonate emotionally to others' positive and negative affect displays, and that these responses become stronger towards emotions with negative valence around the age of 12-months. In this study we measured 6- and 12-month-old infants' changes in pupil diameter when presented with the image and sound of peers experiencing happiness, distress and an emotionally neutral state. For all participants the perception of another's distress triggered larger pupil diameters. Perceiving other's happiness also induced larger pupil diameters but for shorter time intervals. Importantly, we also found evidence for an asymmetry in autonomous arousal towards positive versus negative emotional displays. Larger pupil sizes for another's distress compared to another's happiness were recorded shortly after stimulus onset for the older infants, and in a later time window for the 6-month-olds. These findings suggest that arousal responses for negative as well as for positive emotions are present in the second half of the first postnatal year. Importantly, an asymmetry with stronger responses for negative emotions seems to be already present at this age.

Sensory storage shows a short-lived part-report advantage that survives an aftercoming visual noise pattern (Smithson & Mollon, 2006). We tested whether such an advantage survives different types of high-contrast mask. The target was a 3 × 4 array of digits. The mask could be (a) a noise pattern, (b) an array of eights, or (c) an array of random digits. In a preliminary experiment, target and mask were interleaved (at 140 Hz) and target contrast was varied to determine the level at which performance fell to chance. In the main experiment, target and mask were separated by an inter-stimulus-interval (ISI) of 100, 150, or 200 ms. An auditory part-report cue that was presented 240 ms after target offset supported a part-report advantage at all ISIs for noise masks, at ISIs greater than 100 ms for digit-8 masks, but not at any ISI for random-number masks. Increasing cue delay, in the range 240 to 730 ms, produced a decline in the advantages we measured. The differences in part-report superiority with different types of mask call for revision of the model of visual sensory storage as a single canvas on which successive items are superposed. When mask and target are sufficiently different, a representation of low-contrast target digits can be maintained independently of the representation of an aftercoming, high-contrast mask. However, when the same target is followed by a mask composed of high-contrast random digits, an independent representation of the target does not remain available for access.

Excessive stimulation of ionotropic glutamate receptor is associated with glutamate-mediated excitotoxicity, thereby causing oxidative imbalance and mitochondrial dysfunction, resulting in the excitotoxic death of neurons. Eminent role of endoplasmic reticulum under glutamate-induced excitotoxicity has been highlighted in numerous literatures which have been observed to trigger endoplasmic reticulum stress (ER stress) as well as regulating oxidative stress. However, combating ER stress in excitotoxic neurons can provide a novel approach to alleviate the mitochondrial dysfunctioning and ROS generation. Therefore, we propose to investigate the cross-communication of α-amino-3-hydroxy-5-methyl-4-isoxzole-propionate (AMPA) excitotoxicity-induced oxidative injury with ER stress by employing ER stress inhibitor-4-phenlybutyric acid (4-PBA). Male SD rats were divided into four groups viz sham group (group 1), AMPA (10 mM)-induced excitotoxic group (group 2), curative group of AMPA-induced excitotoxic animals given 4-PBA at a dose of 100 mg/kg body weight (group 3), and alone 4-PBA treatment group (100 mg/kg body weight) (group 4). Animals were sacrificed after 15 days of treatment, and hippocampi were analyzed for histopathological examination, ROS, inflammatory markers, mitochondrial dysfunction, and ER stress markers. AMPA-induced excitotoxicity exhibited a significant increase in the levels of ROS, upregulated ER stress markers, inflammation markers, and compromised mitochondrial functioning in the hippocampus. However, 4-PBA administration significantly curtailed the AMPA-induced excitotoxic insult. This study suggests that targeting ER stress with a chemical chaperone can provide a better therapeutic intervention for neurological disorders involving excitotoxicity, and thus, it opens a new avenue to screen chemical chaperones for the therapeutic modalities.

During binocular rivalry, one stimulus is visible (dominant), while the other stimulus is invisible (suppressed); after a few seconds, perception reverses. To determine whether these alternations involve competition between the eyes or between the images, we measured suppression depth to monocular probes. We did so in conventional rival stimuli and in rival stimuli swapping between the eyes at 1.5 Hz (both sorts of rivalry were shown either with or without 18-Hz flicker). The conventional conditions cause rivalry that could involve either competition between the eyes or between the images or both. The eye-swapping conditions cause rivalry that could involve competition between the images. Probes were either a small spot or a contrast increment to one of the rival stimuli. Using both yes-no and forced-choice procedures, we found that conventional conditions yielded large suppression depth and that eye-swapping conditions yielded small suppression depth. Weak suppression during image rivalry is consistent with conventional rivalry's involving competition between eyes and between images and flicker-and-swap rivalry's involving little, if any competition between eyes and mainly competition between images.

Purpose: To investigate visual performance during reading under different illumination sources.Methods: This experimental quantitative study included 40 (20 females and 20 males) emmetropic participants with no history of ocular pathology. The participants were randomly assigned to read a near visual task under four different illuminations (400-lux constant): compact fluorescent light (CFL), tungsten light (TUNG), fluorescent tube light (FLUO), and light emitting diode (LED). Subsequently, we evaluated the participants' experiences of eight symptoms of visual comfort. Results: The mean age of the participants was 19.86 ± 1.09 (range: 18-21) years. There was no statistically significant difference between the reading rates of males and females under the different illuminations (P = 0.99); however, the reading rate was fastest among males under CFL, and among females under FLUO. One way analysis of variance (ANOVA) revealed a strong significant difference (P = 0.001) between males and females (P = 0.002) regarding the visual performance and illuminations. Conclusion: This study demonstrates the influence of illumination on reading rate; there were no significant differences between males and females under different illuminations, however, males preferred CFL and females preferred FLUO for faster reading and visual comfort. Interestingly, neither preferred LED or TUNG. Although energy-efficient, visual performance under LED is poor; it is uncomfortable for prolonged reading and causes early symptoms of fatigue.