Psychophysiology
May 22, 2008
Sahib S. Khalsa, David Rudrauf, António R. Damásio et al.
276 citations
Meditation traditions claim that paying attention to internal body sensations increases awareness of them, but scientific evidence is lacking. Experienced meditators (Tibetan Buddhist and Kundalini) were compared to nonmeditators matched for age and body mass index on a heartbeat detection task, a standard measure of interoceptive awareness. Contrary to predictions, meditators showed no superior performance across several sessions and respiratory conditions. However, meditators consistently rated their interoceptive performance as better and the task as easier. These results suggest that practicing attention to internal body sensations, a core feature of meditation, does not enhance the ability to sense the heartbeat at rest.
Psychophysiology
April 22, 2018
Michael Christopher Melnychuk, Paul M. Dockree, Redmond G. O'Connell et al.
117 citations
The locus coeruleus (LC), a small brain nucleus, regulates both attention and respiration. Optimal attention requires LC activity to match task demands, while LC neurons also respond to carbon dioxide levels, causing respiratory-linked fluctuations in LC activity. This overlap may synchronize breathing and attention, creating subtle oscillations that aid attentional flexibility but can also destabilize it. The authors present original findings of respiration-LC coupling using fMRI and pupil dilation, show that respiratory phase relates to attentional performance, and offer a mathematical model of this coupling. They propose that meditation and pranayama practices enhance attention, emotion, and physiology partly through the LC's role as a nexus in this coupled system.
Psychophysiology
March 27, 2021
Sebastian Olbrich, Katrin H. Preller, Franz X. Vollenweider
34 citations
Lysergic acid diethylamide (LSD) predominantly increases sympathetic nervous system activity, while the serotonin 2A receptor antagonist ketanserin counteracts this effect by increasing parasympathetic tone. In a randomized, placebo-controlled crossover trial, heart rate variability measures showed that sympathetic activity was positively associated and parasympathetic activity negatively associated with the subjective psychedelic effects of LSD. Additionally, placebo heart rate variability measures predicted subjective experiences after LSD intake. This association between trait autonomic nervous system activity and LSD-induced subjective experiences may serve as a candidate biomarker for the effectiveness of LSD in treating psychopathological conditions.
Psychophysiology
February 12, 2016
Ayla Kruis, Heleen A. Slagter, David R. W. Bachhuber et al.
29 citations
Long-term meditators blink less frequently and show a different eyeblink pattern than meditation-naive participants, with high consistency over three time points. This pattern may reflect differences in striatal dopamine activity, as spontaneous eyeblink rate is a peripheral correlate of such activity. An 8-week mindfulness-based stress reduction course did not alter eyeblink rates compared to active or waitlist controls, and a full day of two different meditation types also had no effect. These results suggest either that individual differences in dopaminergic neurotransmission predispose people to meditation, or that long-term, but not short-term, practice induces stable changes in baseline striatal dopaminergic functioning.
Psychophysiology
May 1, 2025
Isaac N Treves, Anna O Tierney, Simon B Goldberg et al.
5 citations
A breath-counting task designed to measure mindfulness in adults was tested in 78 adolescents with high rumination. The task showed fair reliability but did not correlate positively with self-reported mindfulness, either as a trait or in daily life. Unexpectedly, more mindful adolescents performed worse on breath counting, and the task showed negative correlations with observing emotions and body sensations and with nonreactivity. Breath-counting performance was also unrelated to clinical, personality, and executive functioning measures. The findings indicate that, in this population, breath counting may measure only a narrow form of sustained attention and may not capture broader mindfulness qualities or have predictive validity.
Psychophysiology
August 1, 2024
Paweł Orłowski, Justyna Hobot, Anastasia Ruban et al.
5 citations
Regular naturalistic use of classic psychedelics does not appear to alter long-term neural representations of the self, but it may affect how attentional resources are allocated to task-relevant stimuli. In a cross-sectional study comparing 56 experienced psychedelics users (15 or more lifetime uses) with 57 nonusers, no difference was found in the P300 brain response to hearing one's own name, a stimulus that robustly activates self-representation. However, psychedelics users showed a larger P300 response to other people's names and a smaller increase in P300 amplitude when processing task-relevant target names compared to nonusers. These results suggest that while self-representation remains unchanged, regular psychedelic use might subtly shift attentional processing.
Psychophysiology
February 1, 2025
Maik Mylius, Simon Guendelman, Fivos Iliopoulos et al.
4 citations
Expert meditators show a lower decision threshold rather than higher accuracy in detecting near-threshold tactile stimuli, compared to non-meditators who read regularly. Electroencephalography revealed reduced prestimulus alpha power in meditators, suggesting enhanced alpha modulation. A trial-by-trial analysis found a negative correlation between prestimulus alpha activity and tactile perception. Meditators also reported greater interoceptive sensibility, less emotional suppression, and fewer difficulties describing feelings. These findings suggest that enhanced tactile perception in meditators may stem from reduced sensory filtering in the somatosensory cortex, increasing response rates without improving accuracy.
Psychophysiology
July 1, 2025
Kinga Ciupińska, Marcin Koculak, Michał Bola et al.
2 citations
Comparing brain signals for visual and auditory conscious awareness in the same people shows that early awareness negativity (VAN and AAN) relates to awareness in both senses, but late positivity (LP) relates to awareness only for vision. Visual components also reach consciousness faster than auditory ones. No correlations between modalities in perceptual thresholds or ERP latencies and amplitudes suggest visual and auditory awareness mechanisms are largely separate and modality-specific, not tracking consciousness independently of content.
Psychophysiology
June 1, 2025
Yanfen Zhen, Pei Liu, Lin Jiang et al.
2 citations
Adolescents who engage in nonsuicidal self-injury (NSSI) show deficits in cognitive control, reflected in lower accuracy and sensitivity on an emotional go/no-go task, along with reduced P3 amplitude and theta power measured by EEG. A brief 10-minute deep breath meditation intervention, but not natural breath meditation, restored the decreased no-go theta power in these adolescents. Resting-state EEG microstate D, which reflects attention network activation, differed between meditation strategies and predicted NSSI remission one month later. The findings identify inhibition deficits and specific neural markers (P3, theta power, microstate D) that may aid diagnosis, track intervention effects, and forecast outcomes.
Psychophysiology
June 1, 2026
Tongxin Liu, Sonja A. Kotz, Antonio Criscuolo et al.
1 citation
Spontaneous pupil fluctuations during rest offer a non-invasive, low-cost index of central arousal dynamics. This review synthesizes evidence on the resting-state pupil-brain system, focusing on central neuromodulatory circuits and large-scale cortical networks. It examines the relationship between pupil fluctuations and the ascending arousal system, including noradrenergic, cholinergic, serotonergic, and dopaminergic nuclei, and details coupling with intrinsic functional networks—default mode, salience, and sensorimotor systems. Converging evidence from animal and human neuroimaging studies reveals robust spatiotemporal and spectral coupling between pupil fluctuations and neural activity across micro- and macro-scales. The findings support a systems-level framework where pupil fluctuations serve as integrative markers linking subcortical neuromodulation with large-scale cortical dynamics, with potential utility as biomarkers for neuropsychiatric conditions and altered states of consciousness.
Psychophysiology
May 1, 2025
Qin Huang, Anmin Li
1 citation
Unconscious processing plays a significant role in cognitive control, affecting how we resolve conflicts. In two experiments involving 60 participants, subliminal Stroop primes influenced brain activity, specifically showing Stroop effects on N450 amplitudes. Participants exhibited slower reaction times when previously exposed to conflicting primes, indicating that early unconscious conflict detection impacts conscious decision-making. However, there was no evidence supporting unconscious conflict resolution. These findings underscore the complexities of cognitive control and the neural mechanisms involved in managing conflicts without conscious awareness.
Psychophysiology
January 1, 2026
Neel Muzumdar, Kelly Sun, Samuel Zhang et al.
Volitional sighing at fixed intervals produces a sympathetic cardiovascular response similar to exercise, with heart rate, low-frequency heart rate variability, pulse transit time variability, mean arterial pressure, and low-frequency blood pressure variability all increasing significantly from baseline. Greater changes occurred during shorter intervals between sighs (one every 15 seconds versus one every 30 seconds). High-frequency heart rate variability decreased only during the more frequent sighing task. Males showed larger increases than females in heart rate and several sympathetic indices, but smaller decreases in high-frequency heart rate variability. The fixed-interval volitional sighing protocol may serve as a stress test to detect early cardiovascular or autonomic dysfunction.