Exploring physiological stress response evoked by passive translational acceleration in healthy adults: a pilot study utilizing electrodermal activity and heart rate variability measurements.

Passive translational acceleration (PTA) has been demonstrated to induce the stress response and regulation of autonomic balance in healthy individuals. Electrodermal activity (EDA) and heart rate variability (HRV) measurements are reliable indicators of the autonomic nervous system (ANS) and can be used to assess stress levels. The objective of this study was to investigate the potential of combining EDA and HRV measurements in assessing the physiological stress response induced by PTA. Fourteen healthy subjects were randomly assigned to two groups of equal size. The experimental group underwent five trials of elevator rides, while the control group received a sham treatment. EDA and HRV indices were obtained via ultra-short-term analysis and compared between the two groups to track changes in the ANS. In addition, the complexity of the EDA time series was compared between the 4 s before and the 2-6 s after the onset of PTA to assess changes in the subjects' stress levels in the experimental group. The results revealed a significant increase in the skin conductance response (SCR) frequency and a decrease in the root mean square of successive differences (RMSSD) and high frequency (HF) components of HRV. In terms of stress assessment, the results showed an increase in the complexity of the EDA time series 2-6 s after the onset of PTA. These results indicate an elevation in sympathetic tone when healthy subjects were exposed to a translational transport scenario. Furthermore, evidence was provided for the ability of EDA complexity to differentiate stress states in individual trials of translational acceleration.

Word-Level and Sentence-Level Automaticity in English as a Foreign Language (EFL) Learners: A Comparative Study.

The present study aimed to investigate second language (L2) word-level and sentence-level automatic processing among English as a foreign language students through a comparative analysis of students with different proficiency levels. As a multidimensional and dynamic construct, automaticity is conceptualized as processing speed, stability, and accuracy which are indexed by reaction time, coefficient variation and accuracy rate. Sixty students (39 undergraduate students and 21 graduate students) who majored in English participated in this study. They completed the lexical semantic classification task, the sentence construction task, the sentence verification task under two different modalities (visually- and aurally-presented situations). Multivariate analyses were conducted to examine the differences between the students with different proficiency levels pertaining to their L2 performance. The results indicated that the processing speed was not found to be a good indicator of automatic language processing. Moreover, both levels of students appeared to reach a plateau in word-level processing but there were some variations in students' sentential processing. Finally, the findings showed that automatic language processing seemed to be module-specific and non-sharable across different modalities and skills.