Biology subjects

Piorecky, M.

Publications and source records attributed to Piorecky, M..

3 recordsLinked to original sources

bioRxiv2025

Bright Light Exposure Reduces Negative Affect and Modulates EEG Activity in Sleep-Deprived and Well-Rested Adolescents

This study investigated whether a single morning session of bright light exposure modulates alertness, cognition, mood, and EEG activity in well-rested and partially sleep-deprived adolescents. Forty-seven subjects (15 - 21 years) were assigned to a well-rested (8 h sleep; 9 men, 15 women) or a sleep-deprived group (4 h sleep; 11 men, 12 women). All underwent 30 minutes of morning bright light exposure, with EEG, cognitive testing, and ratings of sleepiness and affect conducted pre- and post-intervention. Behavioral and electrophysiological changes were compared within and between groups. Associations between changes in EEG activity and behavioral outcomes were explored using correlation analyses. Bright light significantly reduced negative affect and improved Digit Span Forward task performance. No changes were observed in positive affect, subjective sleepiness, or Digit Span Backward scores. EEG analysis revealed decreased delta activity in the anterior cingulate cortex and increased beta activity in the right insula and fronto-parietal regions. Behavioral and EEG effects were similar across groups; however, only in the sleep-deprived group changes in beta activity significantly correlated with reduced negative affect. These results suggest that bright light may acutely enhance emotional state, cognitive performance, and cortical arousal in adolescents. The link between beta activity and affective improvement under sleep deprivation suggests a potential mechanism by which light supports emotional regulation.

neuroscience↗

bioRxiv2025

Microstate in rats EEG: a proof of concept study

The electroencephalogram (EEG) reflecting brain activity can be characterized through brief periods of stable neural activity patterns that recur over time and are referred to as microstates. Microstates are related to a range of cognitive processes, and their analysis has become an increasingly popular tool for studying human brain function. While microstates have been extensively studied in humans, their presence and characteristics in animal models have yet to be as thoroughly investigated. This study aims to address this gap by detecting and characterizing microstates in EEGs of rats collected using a superficial electrode system corresponding to homological areas of the human 10-20 system. Specifically, we demonstrate the presence of microstates in rats EEG; those can be captured by the same metrics as in humans. We define these microstates, describe them through topology and parameters, and identify the EEG frequency bands and intracranial sources that predominantly determine microstate topography. These findings have important implications for the use of microstates as a preclinical tool for investigating brain functions, detecting new biomarkers of brain diseases, and translating this knowledge to humans.

animal behavior and cognition↗

bioRxiv2024

Unveiling Stimulus Transduction Artifacts in Auditory Steady-State Response Experiments: Characterization, Risks, and Mitigation Strategies

This scientific paper addresses the potential risk of spurious responses in neuroscientific auditory steady-state response (ASSR) experiments attributed to transduction artifacts. The focus is particularly on click train stimuli, given their spectral content in the frequency range of interest (e.g., 40 Hz). Building upon a pilot experiment demonstrating the existence of the artifact in a phantom head, this study focuses on the characterization of stimulus artifacts in extended measurements with phantoms and the evaluation of associated risks in experiments involving human subjects. The investigation is divided into two parts: the first part scrutinizes stimulus artifact properties crucial for mitigation, while the second part assesses risks in ASSR experiments with human subjects based on the characterized artifact. The discussion covers stimulus characterization, experimental setups with phantoms, and experiments with human subjects, exploring potential sources of the artifact, its spatial properties, and the influence of re-referencing. The results reveal the role of headphone cables as a source of stimulus artifacts, along with the surprising impact of headphone transducers. The study emphasizes the need for careful experimental design and data analysis to avoid misinterpretations of stimulus artifacts as genuine brain responses in ASSR experiments.

neuroscience↗