Investigating letter recognition in the brain by varying typeface: An event-related potential study

Font disfluency and reading performance in children: An event-related potential study

Expert adult readers process fluent and disfluent fonts differently, at both early perceptual and late higher-order processing stages. This finding has been interpreted as reflecting the more difficult to read disfluent fonts requiring greater neural resources. We aimed to investigate whether neural activity is affected by font disfluency in pre-adolescent readers, and to determine if neural responses are related to reading performance. Thirty-three participants between 8 and 12 years old completed two one-back tasks using letter and word stimuli, where font was manipulated (fluent versus disfluent stimuli), during which electroencephalography was recorded. Event related potentials (ERPs) were calculated relative to non-target stimuli for both tasks. The Woodcock Johnson III Tests of Achievement reading specific tests, and the Castles and Coltheart Test 2 were also collected. Font (fluent versus disfluent stimuli) did not consistently affect neural activity during both the letter and word tasks. Fluent stimuli elicited greater late activity (450-600 ms) than disfluent stimuli during the word task, suggesting easy-to-read fonts may enhance the maintenance of words in visual working memory and facilitate the retrieval of semantic information. However, reading performance was not associated with neural disfluency effects, suggesting that pre-adolescents are still at an early developmental reading period. Font manipulation may be a useful way to track developmental reading trajectories in the brain.

MicroRNA-29a-3p Reduces TNFα-Induced Endothelial Dysfunction by Targeting Tumor Necrosis Factor Receptor 1

miR-29a-3p has been shown to be associated with cardiovascular diseases; however, the effect of miR-29a-3p on endothelial dysfunction is unclear. This study aimed to reveal the effects and mechanisms of miR-29a-3p on endothelial dysfunction. The levels of vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and E-selectin were determined by real-time PCR and immunofluorescence staining to reveal the degree of tumor necrosis factor alpha (TNFα)-induced endothelial dysfunction. A luciferase activity assay and cell transfection with a miR-29a-3p mimic or an inhibitor were used to reveal the underlying mechanisms of miR-29a-3p action. Furthermore, the effects of miR-29a-3p on endothelial dysfunction were assessed in C57BL/6 mice injected with TNFα and/or a miR-29a-3p agomir. The results showed that the expression of TNFα-induced adhesion molecules in vascular endothelial cells (EA.hy926 cells, human aortic endothelial cells [HAECs], and primary human umbilical vein endothelial cells [pHUVECs]) and smooth muscle cells (human umbilical vein smooth muscle cells [HUVSMCs]) was significantly decreased following transfection with miR-29a-3p. This effect was reversed by cotransfection with a miR-29a-3p inhibitor. As a key target of miR-29a-3p, tumor necrosis factor receptor 1 mediated the effect of miR-29a-3p. Moreover, miR-29a-3p decreased the plasma levels of TNFα-induced VCAM-1 (32.62%), ICAM-1 (38.22%), and E-selectin (39.32%) in vivo. These data indicate that miR-29a-3p plays a protective role in TNFα-induced endothelial dysfunction, suggesting that miR-29a-3p is a novel target for the prevention and treatment of atherosclerosis.

The time course of visual influences in letter recognition

This study builds on a specific characteristic of letters of the Roman alphabet-namely, that each letter name is associated with two visual formats, corresponding to their uppercase and lowercase versions. Participants had to read aloud the names of single letters, and event-related potentials (ERPs) for six pairs of visually dissimilar upper- and lowercase letters were recorded. Assuming that the end product of processing is the same for upper- and lowercase letters sharing the same vocal response, ERPs were compared backward, starting from the onset of articulatory responses, and the first significant divergence was observed 120 ms before response onset. Given that naming responses were produced at around 414 ms, on average, these results suggest that letter processing is influenced by visual information until 294 ms after stimulus onset. This therefore provides new empirical evidence regarding the time course and interactive nature of visual letter perception processes.