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We report a theoretical investigation of a new carbon nanobelt called Hexa-Penta-belt with molecular formula C $_{42}$ 42 H $_{18}$ 18 . Hexa-Penta-belt is a variation of the synthesised Methylene-bridged[6]cycloparaphenylene (M-b[6]CPP) with molecular formula C $_{42}$ 42 H $_{24}$ 24 . Hexa-Penta-belt consists of carbon pentagon and hexagon rings and was inspired by the Penta-belt (theoretically derived from the penta-graphene sheet), the [12]cyclophenacene, and the M-b[6]CPP synthesised by Itami and Segawa [1]. Using Density Functional Theory (DFT), we calculated Hexa-Penta-belt electronic, optical, and thermodynamic properties and their vibrational frequencies. Hexa-Penta-belt is a structurally and thermally stable molecule, as Quantum Molecular Dynamics (QMD) showed. The results exhibited that the Hexa-Penta-belt has excellent electronic stability comparable to C $_{60}$ 60 , and it behaves as a semiconductor with a gap estimated at 0.89 eV. It absorbs in the ultraviolet and the visible region (corresponding to the violet, green, and red colours) presenting an absorption more consistent in the visible region than M-b[6]CPP, which could indicate application, for example, as an optical nanosensor. We verified through the carbon atom binding energy that Hexa-Penta-belt is an intermediate molecule between Penta-belt and [12]cyclophenacene. [ABSTRACT FROM AUTHOR]

Prior expectations shape neural responses in sensory regions of the brain, consistent with a Bayesian predictive coding account of perception. Yet, it remains unclear whether such a mechanism is already functional during early stages of development. To address this issue, we study how the infant brain responds to prediction violations using a cross-modal cueing paradigm. We record electroencephalographic responses to expected and unexpected visual events preceded by auditory cues in 12-month-old infants. We find an increased response for unexpected events. However, this effect of prediction error is only observed during late processing stages associated with conscious access mechanisms. In contrast, early perceptual components reveal an amplification of neural responses for predicted relative to surprising events, suggesting that selective attention enhances perceptual processing for expected events. Taken together, these results demonstrate that cross-modal statistical regularities are used to generate predictions that differentially influence early and late neural responses in infants. [ABSTRACT FROM AUTHOR]

Proper neural connectivity inference has become essential for understanding cognitive processes associated with human brain function. Its efficacy is often hampered by the curse of dimensionality. In the electroencephalogram case, which is a noninvasive electrophysiological monitoring technique to record electrical activity of the brain, a possible way around this is to replace multichannel electrode information with dipole reconstructed data. We use a method based on maximum entropy and the renormalization group to infer the position of the sources, whose success hinges on transmitting information from low- to high-resolution representations of the cortex. The performance of this method compares favorably to other available source inference algorithms, which are ranked here in terms of their performance with respect to directed connectivity inference by using artificially generated dynamic data. We examine some representative scenarios comprising different numbers of dynamically connected dipoles over distinct cortical surface positions and under different sensor noise impairment levels. The overall conclusion is that inverse problem solutions do not affect the correct inference of the direction of the flow of information as long as the equivalent dipole sources are correctly found. [ABSTRACT FROM AUTHOR]

Face processing relies on predictive processes driven by low spatial frequencies (LSF) that convey coarse information prior to fine information conveyed by high spatial frequencies. However, autistic individuals might have atypical predictive processes, contributing to facial processing difficulties. This may be more normalized in autistic females, who often exhibit better socio-communicational abilities than males. We hypothesized that autistic females would display a more typical coarse-to-fine processing for socio-emotional stimuli compared to autistic males. To test this hypothesis, we asked adult participants (44 autistic, 51 non-autistic) to detect fearful faces among neutral faces, filtered in two orders: from coarse-to-fine (CtF) and from fine-to-coarse (FtC). Results show lower d' values and longer reaction times for fearful detection in autism compared to non-autistic (NA) individuals, regardless of the filtering order. Both groups presented shorter P100 latency after CtF compared to FtC, and larger amplitude for N170 after FtC compared to CtF. However, autistic participants presented a reduced difference in source activity between CtF and FtC in the fusiform. There was also a more spatially spread activation pattern in autistic females compared to NA females. Finally, females had faster P100 and N170 latencies, as well as larger occipital activation for FtC sequences than males, irrespective of the group. Overall, the results do not suggest impaired predictive processes from LSF in autism despite behavioral differences in fear detection. However, they do indicate reduced brain modulation by spatial frequency in autism. In addition, the findings highlight sex differences that warrant consideration in understanding autistic females., (© 2024 The Author(s). Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)