Biology subjects

Zamorano, A. M.

Publications and source records attributed to Zamorano, A. M..

5 recordsLinked to original sources

bioRxiv2026

Resilience to persistent pain is characterized by stable periodic and increased aperiodic cortical activity

Individual variability in pain perception raises fundamental questions about how biological and experiential factors shape pain processing. Cognitive-demanding motor training is a key driver of use-dependent brain plasticity and may contribute to differences in pain responses. Using musicians as a model of cognitive-motor expertise, we examined how such experience influences cortical dynamics and pain perception during experimentally induced prolonged musculoskeletal pain. Resting-state electroencephalography (EEG) was recorded in musicians and non-musicians before (Day 1) and during pain development (Days 3 and 8) following intramuscular nerve growth factor (NGF) administration. We parameterized periodic (alpha peak frequency, power, frontal asymmetry) and aperiodic (exponent, offset) components of the EEG signal to characterize intrinsic cortical activity. During pain development, non-musicians exhibited slowing of peak alpha frequency, a neural marker associated with ongoing pain. In contrast, musicians showed preserved alpha dynamics and greater left frontal asymmetry, reflecting resilient top-down pain regulation. Musicians also displayed higher aperiodic exponent across sessions, suggesting that musical training shapes the excitation-to-inhibition (E:I) balance potentially reflecting a shift toward greater inhibitory activity. Notably, across all participants, only aperiodic features improved the prediction of pain severity, with higher exponents and higher offsets associated with lower pain ratings. These findings demonstrate that cognitive-motor training shapes cortical dynamics during sustained pain, supporting more stable, resilient cortical responses to pain. Such training also contributes to inter-individual variability in pain processing. Moreover, this study identifies aperiodic EEG components as predictors of pain severity and resilience.

neuroscience↗

bioRxiv2025

Embodied Singing: Dual Role of Interoception in Vocal Expertise and Musical Competence

Musical expertise is often associated with heightened perceptual sensitivity to external sensory stimuli, yet its relationship with internal bodily awareness (interoception) remains elusive. This study examined whether interoceptive ability relates differentially to varying levels of singing expertise and explored if interoception could predispose individuals to musical skills. Professional singers, amateur singers, and non-singers completed a heartbeat discrimination task (interoceptive accuracy; IAcc), self-reported interoceptive sensibility assessment, and comprehensive musical competence measures. Results demonstrated a significant positive association between singing expertise and IAcc, which notably emerged only in professional singers, who significantly outperformed both amateur singers and non-singers. Regression analyses indicated a moderate predictive role of accumulated singing practice for IAcc among trained singers, though emotional awareness partially mediated the relationship between expertise and IAcc. Critically, higher IAcc in non-singers significantly correlated with superior singing accuracy, suggesting enhanced interoception may facilitate singing competence independently of formal vocal training. Altogether, these findings highlight a dual role of interoception, linking it to expert-level singing--partially mediated by emotional awareness-- and independently to musical competence in non-singers. These results reconcile prior inconsistencies by highlighting the embodied nature of singing and the distinct role of musical expertise, while underscoring inherent musically relevant mechanisms beyond practice alone.

neuroscience↗

bioRxiv2025

Increased Callosal Thickness in Early Trained Opera Singers

Extensive research has shown how the corpus callosum adapts to early sensorimotor training in instrumental musicians, yet less is known about these effects in professional singers. This study used high-resolution MRI to investigate variations in callosal thickness in relation to vocal training in 55 participants, including 27 professionally trained opera singers and 28 non-singers. Results indicated trend-level differences with thicker callosal regions in singers, particularly at the anterior-posterior midbody border and the isthmus, though these did not survive corrections for multiple comparisons. However, a significant negative correlation between age at first singing lesson and callosal thickness was found in the anterior third (rostrum, genu, rostral body), the anterior-posterior midbody border, and the isthmus, suggesting that early vocal training facilitates lasting neuroplastic adaptations in these regions. Additionally, a positive trend between years of professional singing and greater thickness in the midbody was observed but did not remain significant after correction for multiple comparisons. Greater callosal thickness likely enhances interhemispheric connectivity to meet the demands of operatic performance, highlighting the adaptability of the corpus callosum to early, sustained sensorimotor training. By extending evidence from instrumental musicians to singers, these results underscore developmental timing as a key factor in how sensorimotor training shapes brain structure.

neuroscience↗

bioRxiv2025

Prior use-dependent plasticity triggers different individual corticomotor responses during persistent musculoskeletal pain

Movement repetition is crucial for pain interventions. It facilitates the rehabilitation of motor patterns, the acquisition of motor skills and the genesis of adaptive use-dependent plasticity. However, the influence of prior motor experience and pre-existing use-dependent plasticity on pain severity and progression remains poorly investigated. This study investigated the effects of pre-existing use-dependent plasticity during the development of prolonged experimental musculoskeletal pain. Using transcranial magnetic stimulation, corticospinal excitability was assessed by measuring the rest-motor thresholds (RMTs), motor-evoked potential (MEP), representational area of the motor map, volume, and center of gravity of the first dorsal interosseous (FDI) muscle in musicians (n=19), a well-known ecological model of use-dependent plasticity, and in non-musicians (n=20). All participants attended three sessions (Day1, Day3, Day8). Prolonged pain for several days was induced by intramuscular injection of nerve growth factor (NGF) into the right FDI muscle at the end of Day1. Compared to Day1, prolonged pain uniquely led to reduced motor map volume in non-musicians on Day3 (p=0.004), who also showed higher NGF-related pain intensity compared to musicians. The motor maps of musicians, which were already smaller in pain-free conditions (Day1) compared to non-musicians (p=0.021), remained non-significantly different across days. Notably, corticomotor responses (map volume, MEP amplitude, and RMTs) at Day1 were correlated to weekly and accumulated musical training. These findings demonstrate that pre-existing use-dependent plasticity associated with motor training may counteract the effects of prolonged pain in the motor system. Moreover, it confirms that prior motor experience acts as a source of individual variability to pain.

neuroscience↗

bioRxiv2020

Use-dependent plasticity enhances nociceptive and non-nociceptive somatosensory cortical responses in healthy individuals

Repetitive movements and multisensory integration promote use-dependent plasticity, which has been consistently demonstrated using musical training as a model. Prolonged and repeated execution of motor patterns is also a main risk factor for developing pain syndromes, yet the neural underpinnings that link repetitive movements and use-dependent plasticity to abnormal pain processing in humans are unknown. Employing nociceptive and non-nociceptive electrical stimulation to evoke brain responses, we demonstrate that healthy musicians compared to non-musicians show larger non-nociceptive N140 and nociceptive N200 responses, smaller non-nociceptive P200 responses, and faster reaction times (RTs) to both stimuli. Across participants, larger N140 and N200 amplitudes predicted the RTs, whereas amount of daily practice in musicians predicted RTs, non-nociceptive P200, and nociceptive P300 components. These novel findings indicate that the mechanisms by which repetitive sensorimotor training and multimodal integration promote neural plasticity in multisensory neural structures may also increase stimulus-selectivity to nociceptive cues in healthy individuals.

neuroscience↗