Biology subjects

Schultz, B. G.

Publications and source records attributed to Schultz, B. G..

3 recordsLinked to original sources

bioRxiv2021

The human FLT1 regulatory element directs vascular expression and modulates angiogenesis pathways in vitro and in vivo

There is growing evidence that mutations in non-coding cis-regulatory elements (CREs) disrupt proper development. However, little is known about human CREs that are crucial for cardiovascular development. To address this, we bioinformatically identified cardiovascular CREs based on the occupancy of the CRE by the homeodomain protein NKX2-5 and cardiac chromatin histone modifications. This search defined a highly conserved CRE within the FLT1 locus termed enFLT1. We show that the human enFLT1 is an enhancer capable of driving reporter transgene expression in vivo throughout the developing cardiovascular system of medaka. Deletion of the human enFLT1 enhancer ({Delta}enFLT1) triggered molecular perturbations in extracellular matrix organisation and blood vessel morphogenesis in vitro in endothelial cells derived from human embryonic stem cells and vascular defects in vivo in medaka. These findings highlight the crucial role of the human FLT1 enhancer and its function as a regulator and buffer of transcriptional regulation in cardiovascular development.

genomics↗

bioRxiv2020

Left frontal motor delta oscillations reflect the temporal integration of multimodal speech

During multimodal speech perception, slow delta oscillations (~1 - 3 Hz) in the listeners brain synchronize with speech signal, likely reflecting signal decomposition at the service of comprehension. In particular, fluctuations imposed onto the speech amplitude envelope by a speakers prosody seem to temporally align with articulatory and body gestures, thus providing two complementary sensations to the speech signals temporal structure. Further, endogenous delta oscillations in the left motor cortex align with speech and music beat, suggesting a role in the temporal integration of (quasi)-rhythmic stimulations. We propose that delta activity facilitates the temporal alignment of a listeners oscillatory activity with the prosodic fluctuations in a speakers speech during multimodal speech perception. We recorded EEG responses in an audiovisual synchrony detection task while participants watched videos of a speaker. To test the temporal alignment of visual and auditory prosodic features, we filtered the speech signal to remove verbal content. Results confirm (i) that participants accurately detected audiovisual synchrony, and (ii) greater delta power in left frontal motor regions in response to audiovisual asynchrony. The latter effect correlated with behavioural performance, and (iii) decreased delta-beta coupling in the left frontal motor regions when listeners could not accurately integrate visual and auditory prosodies. Together, these findings suggest that endogenous delta oscillations align fluctuating prosodic information conveyed by distinct sensory modalities onto a common temporal organisation in multimodal speech perception.

neuroscience↗

bioRxiv2020

Effects of face masks on acoustic analysis and speech perception: Implications for peri-pandemic protocols

Wearing face masks (alongside physical distancing) provides some protection against infection from COVID-19. Face masks can also change how we communicate and subsequently affect speech signal quality. Here we investigated how three face mask types (N95, surgical and cloth) affect acoustic analysis of speech and perceived intelligibility in healthy subjects. We compared speech produced with and without the different masks on acoustic measures of timing, frequency, perturbation and power spectral density. Speech clarity was also examined using a standardized intelligibility tool by blinded raters. Mask type impacted the power distribution in frequencies above 3kHz for both the N95 and surgical masks. Measures of timing and spectral tilt also differed across mask conditions. Cepstral and harmonics to noise ratios remained flat across mask type. No differences were observed across conditions for word or sentence intelligibility measures. Our data show that face masks change the speech signal, but some specific acoustic features remain largely unaffected (e.g., measures of voice quality) irrespective of mask type. Outcomes have bearing on how future speech studies are run when personal protective equipment is worn.

bioengineering↗