Facilitating or disturbing? An investigation about the effects of auditory frequencies on prefrontal cortex activation and postural sway

Abstract

Auditory stimulation activates brain areas associated with higher cognitive processes, like the prefrontal cortex (PFC), and plays a role in postural control regulation. However, the effects of specific frequency stimuli on upright posture maintenance and PFC activation patterns remain unknown. Therefore, the study aims at filling this gap. Twenty healthy adults performed static double- and single-leg stance tasks of 60s each under four auditory conditions: 500, 1000, 1500, and 2000 Hz, binaurally delivered through headphones, and in quiet condition. Functional near-infrared spectroscopy was used to measure PFC activation through changes in oxygenated hemoglobin concentration, while an inertial sensor (sealed at the L5 vertebra level) quantified postural sway parameters. Perceived discomfort and pleasantness were rated through a 0–100 visual analogue scale (VAS). Results showed that in both motor tasks, different PFC activation patterns were displayed at the different auditory frequencies and the postural performance worsened with auditory stimuli, compared to quiet conditions. VAS results showed that higher frequencies were considered more discomfortable than lower ones. Present data prove that specific sound frequencies play a significant role in cognitive resources recruitment and in the regulation of postural control. Furthermore, it supports the importance of exploring the relationship among tones, cortical activity, and posture, also considering possible applications with neurological populations and people with hearing dysfunctions.

Analysis of Head Micromovements and Body Posture for Vigilance Decrement Assessment

“…Lower resources are instead dedicated to PVT execution, leading to a decrease in performance, as highlighted by the increase in RT. As a matter of fact, previous studies have pointed out that, when the vestibular system is challenged, maintaining the same balance and posture starts to be cognitively demanding [1,2,66]. However, on the other hand, the incorporation of vestibular stimulation, like swinging on a swing during leisure time, as suggested in [67], over time could instead improve cognitive function.…”

Editorial: The brain meets the body: neural basis of cognitive contribution in movement for healthy and neurological populations

“…Authors outlined how visual-vestibular interactions enhance postural stability by interpreting the head's position and generating eye movements accordingly, which helps differentiate self-motion or external motion and achieve gaze stabilization and postural control. Indirect measurement of brain responses to postural changes is also addressed through the assessment of neuromuscular and motor functions, as in the investigation of defense mechanisms adopted to keep the body away from the stimulus (Graziano and Cooke, 2006 ; Belluscio et al, 2023 ). In humans the space directly surrounding the body at a grasping distance has been depicted as defensive peripersonal space for tactile (Rizzolatti et al, 1997 ) or auditory stimulation (Ladavas et al, 2001 ), closer the stimulation to the head stronger behavioral response was found (Versace et al, 2019 ).…”

Pentatonic sequences and monaural beats to facilitate relaxation: an EEG study

“…Specifically, we used a C minor pentatonic scale (C3, Eb3, F3, G3, Bb3, C4) because minor music tends to be perceived as less arousing, more contemplative, and sadder ( Parncutt, 2014 ). Furthermore, the scale was chosen in the middle-low register (C3–C4), avoiding high-pitch tones that are mostly associated with alarm, tension, and arousal ( McAdams et al, 2017 ; Belluscio et al, 2023 ). In fact, high-pitch tones are frequently used to alarm and capture attention (e.g., Straughn et al, 2009 ; Belluscio et al, 2023 ).…”

“…Furthermore, the scale was chosen in the middle-low register (C3–C4), avoiding high-pitch tones that are mostly associated with alarm, tension, and arousal ( McAdams et al, 2017 ; Belluscio et al, 2023 ). In fact, high-pitch tones are frequently used to alarm and capture attention (e.g., Straughn et al, 2009 ; Belluscio et al, 2023 ). To keep the timbre as simple as possible pure tones were used.…”