Does Platelet-Rich Plasma Deserve a Role in Accelerating the Recovery of Reflex Sympathetic Dystrophy Following Distal Radius Fracture?

Introduction: This study was to evaluate the efficacy of multiple platelet-rich plasma injections in reflex sympathetic dystrophy following distal radius fracture after previous various treatments have failed. Materials and methods: This comparative prospective study was designed for 64 patients of reflex sympathetic dystrophy developed following distal radius fracture, from January 2009 to December 2020 were enrolled in this study. This cohort of patient was given either four multiple subcutaneous platelet-rich plasma injections at weekly interval (n = 32) or two injections in a month with 15 days interval (n = 32). The primary outcome measure assessed with patient rated wrist evaluation questionnaire score. The secondary outcome was a visual analogue scale pain score. The final follow up was at 2 years. p ≤ 0.05 is considered statistically. Results: The patient rated wrist evaluation score for usual and specific activities and EQ-VAS for pain level showed statistically significant greater improvement in group A (42 ± 21%) compared to group B (19 ± 24%), (p = 0.37). Patients also had improvement in wrist movements with no statistically significant differences in both groups. The standard difference in means of all three functional scores was almost similar between both groups A and B (standard difference in means = 0.032; 95% CI 0.236-0.830; p = 0.495), considered clinically meaningful. Conclusion: This study results suggest autologous platelet-rich plasma injections seem to be safe, cost effective, efficacious algorithm treatment for reflex sympathetic dystrophy following distal radius fracture patients where previous treatments have failed.

Evaluation of the Effect of Benzydamine Hydrochloride on the Intensity of Gag Reflex: A Randomized Single-Blind Clinical Trial.

Statement of the Problem: Gag reflex is among the most common problems during dental and endoscopic procedures. Benzydamine hydrochloride is a non-steroidal anti-inflammatory medication and a local anesthetic that might be useful in reducing the gag reflex. Purpose: This study aimed to evaluate the effects of benzydamine hydrochloride mouthwash on the intensity of the gag reflex. Materials and Method: In this randomized clinical trial study, 30 participants aged 21-26 with a gag trigger point index (GTPI) higher than 2 were divided into 2 groups. In the case group, 15 ml of 0.15% benzydamine hydrochloride mouthwash was gargled for 1 minute, and after 10 minutes GTPI test was conducted. In the control group, 4 puffs of 10% lidocaine spray were applied to the mucosa of the targeted area, and after 5 minutes, GTPI was measured. Participants were asked about the taste and smell of the medications. Results: GTPI was significantly reduced in both groups. In the lidocaine group, the GTPI score changed from 4.47 to 2.00 (p< 0.001), and that for the benzydamine group was 4.20 to 1.47 (p< 0.001). The variance rate of the gag reflex was -2.73 and -2.47 in the benzydamine group and lidocaine group, respectively. However, this reduction was not statistically significant between the two groups. Moreover, benzydamine mouthwash has a significantly better taste and smell than lidocaine (p= 0.001). Conclusion: The results of this study showed that benzydamine mouthwash could be used quite effectively in reducing the gag reflex.

Unusual Presentation of De Winter's Sign Due to Bezold-Jarisch Reflex in a Patient With Severe Aortic Valve Stenosis.

The de Winter electrocardiogram (ECG) pattern, marked by upsloping ST depression in leads V2-V6, ST elevation in lead aVR, and tall symmetric T waves, typically indicates left anterior descending artery (LAD) occlusion. Traditionally linked to LAD occlusion, it is rare in severe aortic stenosis and the Bezold-Jarisch reflex (BJR). We report an 83-year-old man with severe aortic stenosis who developed hypotension due to bleeding and exhibited the de Winter ECG pattern. This case highlights how severe aortic stenosis and BJR can lead to significant hemodynamic instability and ischemic ECG changes, resolving after hemodynamic stabilization.

Trigeminal Cardiac Reflux During Le Fort I Osteotomy: A Case Report.

The trigeminocardiac reflex (TCR) is marked by significant cardiovascular reactions, such as bradycardia and asystole, triggered by trigeminal nerve stimulation. It is described as a brief episode of bradycardia, hypotension, or even cardiac arrest resulting from trigeminal nerve stimulation. The exact cause of TCR is not yet fully understood, but it is believed to involve the release of neurotransmitters, including acetylcholine, and the involvement of central neuronal integration. In this case report, we present an occurrence of trigeminal cardiac reflux during a Le Fort I osteotomy procedure in a patient with no medical issues.

Laughter-Induced Seizures: A Rare Type of Reflex Epilepsy.

This research explores the rare occurrence of laughter-induced seizures, a form of reflex epilepsy documented in only one previous case in the literature. The patient, free from prior medical or neuropsychiatric history, exhibited seizures triggered solely by laughter. Electroencephalography and neuroimaging revealed normal results. Despite declining medical therapy, lifestyle modifications enabled seizure management. The study emphasizes the dearth of data on laughter-induced seizures, prompting the consideration of multimodal strategies for treatment. Further research is imperative to unveil the precise pathophysiology and establish standardized therapeutic approaches for this uncommon epileptic manifestation.

Non-dual awareness and sensory processing in meditators: Insights from startle reflex modulation.

Startle modulation paradigms, namely habituation and prepulse inhibition (PPI), can offer insight into the brain's early information processing mechanisms that might be impacted by regular meditation practice. Habituation refers to decreasing response to a repeatedly-presented startle stimulus, reflecting its redundancy. PPI refers to response reduction when a startling stimulus "pulse" is preceded by a weaker sensory stimulus "prepulse" and provides an operational measure of sensorimotor gating. Here, we examined habituation and PPI of the acoustic startle response in regular meditators (n = 32), relative to meditation-naïve individuals (n = 36). Overall, there was no significant difference between meditators and non-meditators in habituation or PPI, but there was significantly greater PPI in meditators who self-reported being able to enter and sustain non-dual awareness during their meditation practice (n = 18) relative to those who could not (n = 14). Together, these findings suggest that subjective differences in meditation experience may be associated with differential sensory processing characteristics in meditators.

A novel molecular assay conducted on the BD Max system to facilitate reflex testing for vanA and vanB in clinical isolates of enterococci.

Infections caused by vancomycin-resistant enterococci (VRE) are common. Real-time PCR assays targeting vanA and vanB facilitate screening of patients in healthcare settings to limit the risk of dissemination, especially amongst those at high-risk of infection or with limited treatment options. Such assays are commonly performed as reflex testing procedures where they augment phenotypic techniques and shorten turnaround time to benefit timely clinical management. 'Random access' and 'sample-to-result' real-time PCR platforms are suited for this application as they are of low complexity and less technically demanding. Modelled on these attributes, we configured a real-time PCR assay (VRE BD) for detection of vanA/B in clinical isolates of enterococci, adapted for the BD Max System (Becton Dickinson). We applied an unconventional approach by testing suspensions of microorganisms in water to circumvent the traditional pre-analytical genomic extraction process. Our objective of this study was to assess the performance of this assay for detection of VRE in cultures by validating against a traditional real-time PCR assay based on the LightCycler 2.0 platform (Roche, VRE RO). A high level of analytical sensitivity and specificity (≥99.0%) for both genes was obtained when testing suspensions derived from blood agar. Results for suspensions obtained from chromID VRE (Edwards Group) showed a similar level of performance for vanA detection (100%), but not for the vanB target (≥90.9%) where a lesser number of isolates were available for testing. However, our results for VRE detection in isolates from these media were repeatable and reproducible, and equated to positive and negative predictive values of ≥95.2% and ≥97.8%, respectively. Furthermore, the VRE BD assay was also able to accurately detect VRE in clinical and spiked BacT/ALERT (bioMérieux) blood cultures. Thus, the technical simplicity, short turnaround time and robustness of this high performing assay for VRE is suitable for reflex testing. In addition, the format developed for the BD Max platform has potential application for reflex testing other molecular targets of clinical importance.

Factors Influencing Bladder Perforation during Transurethral Resection of Bladder Cancer: A Comprehensive Analysis.

BACKGROUND: Bladder perforation (BP) is one of the important complications during transurethral resection of bladder tumour (TURBT). Additionally, multiple factors can contribute to BP. Here, we investigated the rates of BP, specifically in variant histology of bladder cancer (BC), and examined the clinical follow-up of relevant patients. METHODS: Of the 797 patients who underwent TURBT between 2015 and 2023, they were divided into two groups according to BP during the operation. Group 1 (n = 744) consisted of patients without BP, whereas Group 2 (n = 53) consisted of patients with BP. Demographic, operative, postoperative and follow-up data were investigated and analysed. Groups were examined in terms of causes of BP. Significance was set at p < 0.05. RESULTS: A significantly higher rate of BP was found in patients operated with bipolar energy (p = 0.027) than in their counterparts. In multivariable analysis, the presence of the obturator reflex during TURBT was significantly associated with an increased risk of BP (p < 0.001). We observed a statistically significant increase in the rate of BP in patients with a history of previous intravesical Bacillus Calmette-Guérin (BCG) therapy (p = 0.023). Variant histology was reported in 32 patients (4%). However, we could not find any statistically significant relationship between the development of BP and the variant histology of BC (p = 0.641). CONCLUSIONS: Multiple factors can affect BP during TURBT. Understanding the factors associated with BP is crucial for improving patient safety and outcomes. According to the results of the present study, the energy source, the presence of obturator reflex during TURBT and intravesical BCG therapy may increase BP. Nevertheless, the presence of variant histology was not significantly associated with BP.

Sex and season influence behaviour and physiology of lake trout following angling.

Catch-and-release angling exposes fish to challenges that may result in sub-lethal effects or mortality. Lake trout (Salvelinus namaycush) undergo high rates of release because of size-based harvest regulations or voluntary angler behaviour. Here, we examine short-term impairment in lake trout angled during the summer (n = 74) and fall spawning period (n = 33) to inform best practices for angling. Immediately following capture or 0.5 h post-capture, fish underwent reflex and barotrauma assessments, and a small blood sample was collected. Fish were also fitted with an externally mounted biologger equipped with depth, temperature and tri-axial acceleration sensors, that was tethered to allow retrieval of the logger after 14 min. In the summer, reflex impairment and barotrauma at 0 and 0.5 h were significantly correlated. Loss of orientation and bloating were the most observed indicators. Larger fish and those captured at increased depth had higher barotrauma scores, while prolonged fight times decreased the barotrauma score regardless of sampling time. Plasma cortisol, lactate and glucose increased 0.5 h after capture, and extracellular and intracellular pH decreased, all signs that angling was inducing a metabolic response. However, no relationships were found between blood indices and mortality (18.9%). The time required to reach maximum depth after release was longer for fish with increased air exposure but shorter for those with longer fight times. During the fall, fish displayed no mortality or reflex impairment. Anal prolapse was the most observed indicator of barotrauma but only observed in females. Blood indices were most altered 0.5 h after capture, with increased cortisol values for fish that were female, particularly large or captured at deeper depth. Locomotor activity was highest for males and increased with depth. Together, our findings suggest that the effects of catch-and-release angling may be dependent on several factors, including sex, season and angling depth.

Clinical characteristics and otolith dysfunction in presbyvestibulopathy: A retrospective cross-sectional analysis.

Objective: The Bárány Society recently established diagnostic criteria for presbyvestibulopathy, an age-related bilateral vestibular impairments in older individuals. Drawing upon a cross-sectional database, this study delves into the demographic and clinical features of presbyvestibulopathy patients and investigates the implications of otolith dysfunction. Methods: The study retrospectively analyzed 1218 patients aged 60 years or older who visited the tertiary dizziness clinic in 2020, due to symptoms of dizziness or instability. By reviewing medical records, we gathered clinical information and laboratory vestibular test results, such as cervical and ocular vestibular evoked myogenic potentials, and subjective visual vertical. Results: Out of 1218 patients aged 60 and above who reported dizziness or unsteadiness, 33 patients (2.7 %, with an average age of 74.2 ± 9.2 years) were diagnosed with presbyvestibulopathy. Deficiencies in horizontal angular vestibulo-ocular reflex were found in caloric tests (75 %), video head impulse tests (51.7 %), and rotatory chair tests (47.8 %), respectively. Otolith dysfunction was also observed, as shown by abnormal ocular and cervical vestibular evoked myogenic potentials in 62.96 % and 51.85 % of patients, and abnormal subjective visual vertical in 45.8 % of the cases. Conclusions: Among elderly patients experiencing consistent dizziness or instability, the incidence of presbyvestibulopathy was approximately 2.7 % over one year. Alongside the abnormalities detected in the horizontal angular vestibulo-ocular reflex, significant changes were also noted in the ocular and cervical vestibular evoked myogenic potentials, as well as in the subjective visual vertical tests. As a result, it's vital to underscore the significance of both otolithic function and vestibulo-ocular reflex in the fundamental mechanisms of presbyvestibulopathy.

Preliminary results of classifying otosclerosis and disarticulation using a convolutional neural network trained with simulated wideband acoustic immittance data.

Current noninvasive methods of clinical practice often do not identify the causes of conductive hearing loss due to pathologic changes in the middle ear with sufficient certainty. Wideband acoustic immittance (WAI) measurement is noninvasive, inexpensive and objective. It is very sensitive to pathologic changes in the middle ear and therefore promising for diagnosis. However, evaluation of the data is difficult because of large interindividual variations. Machine learning methods like Convolutional neural networks (CNN) which might be able to deal with this overlaying pattern require a large amount of labeled measurement data for training and validation. This is difficult to provide given the low prevalence of many middle-ear pathologies. Therefore, this study proposes an approach in which the WAI training data of the CNN are simulated with a finite-element ear model and the Monte-Carlo method. With this approach, virtual populations of normal, otosclerotic, and disarticulated ears were generated, consistent with the averaged data of measured populations and well representing the qualitative characteristics of individuals. The CNN trained with the virtual data achieved for otosclerosis an AUC of 91.1 %, a sensitivity of 85.7 %, and a specificity of 85.2 %. For disarticulation, an AUC of 99.5 %, sensitivity of 100 %, and specificity of 93.1 % was achieved. Furthermore, it was estimated that specificity could potentially be increased to about 99 % in both pathological cases if stapes reflex threshold measurements were used to confirm the diagnosis. Thus, the procedures' performance is comparable to classifiers from other studies trained with real measurement data, and therefore the procedure offers great potential for the diagnosis of rare pathologies or early-stages pathologies. The clinical potential of these preliminary results remains to be evaluated on more measurement data and additional pathologies.

Urinalysis is predictive for absence of urinary tract infection in men with and without catheters.

OBJECTIVES: To determine accuracy of negative urinalysis (UA) for predicting negative urine culture and the absence of urinary tract infection (UTI), and optimal urine culture growth cutoff for UTI diagnosis in men with and without urinary catheters. SUBJECTS AND METHODS: UAs with urine cultures within 1 week from adult men were identified and evaluated. Predictive values for the absence of UTI (absence of ≥1 of the following criteria: documentation of UTI diagnosis, antibiotic prescription, uropathogen presence on culture) were calculated. RESULTS: In total, 22 883 UAs were included. Negative UA had a high predictive value for negative urine culture (0.95, 95% confidence interval [CI]: 0.94-0.95) and absence of UTI (0.99, CI: 0.99-0.995) in the overall cohort. Negative UA also had a high predictive value for negative urine culture (0.93, CI: 0.90-0.95) and absence of UTI (0.99, CI: 0.98-0.999) in those with indwelling urinary catheters. The traditional threshold of culture growth of 100 000 colony-forming units (CFU)/mL did not capture 22% of UTIs. CONCLUSION: UA exhibits high predictive value for negative urine culture and absence of UTI in men, supporting a protocol wherein culture is only performed in the context of abnormal UA. The traditional 100 000 CFU/mL cut-off may have not captured a subset of UTI in the male population, and warrants further investigation.

Hot water epilepsy with alone and spontaneous seizures in childhood.

OBJECTIVES: Hot water epilepsy (HWE) is a type of epilepsy that primarily affects children. This study was aimed to evaluate the clinical, electroencephalogram (EEG), neuroimaging findings, and treatment options in children with HWE. METHODS: The medical records of 24 patients who had HWE were evaluated retrospectively. RESULTS: There were 2767 patients diagnosed with epilepsy during the seven-year period, and 0.86 % of the patients had HWE. The median age of the patients was three (range 1.2-7 years), with a male predominance (male/female ratio: 7.1). Six patients (25 %) had HWE with spontaneous seizures (HWESS) and 18 patients (75 %) had HWE alone (HWEA). 11 patients had focal onset seizures, 13 patients had generalized onset seizures. EEG abnormalities were found in 7 patients (29.2 %). Three patients (12.5 %) had nonspecific MRI findings. Developmental abnormalities (autism spectrum disorder, learning disability and speech disturbance.) were detected in 8 patients (33.3 %). Only one patient's (4.2 %) seizure could be controlled by changing bathroom habits. Twenty-three patients (95.8 %) were given antiepileptic drugs. 18 of 24 patients had come for follow-up visits for two years, nine of them used monotherapy and seizures did not recur. The treatment response was 55.5 %. Oxcarbazepine (8 patients, 33.3 %) and valproic acid (7 patients, 29.2 %) were the most chosen two drugs for HWE. The genetic tests performed were not accepted relevant to the patients' clinical conditions and epilepsy. CONCLUSION: The frequency of the HWE was not as high in the literature. Male predominance, EEG abnormalities may be seen. Changing bath room habits did not improve the treatment as a first line management, all the patients except one used antiepileptic drug treatment. Until now, there has been no study in Turkey showing the frequency of HWE exclusively in children.

Effect of stimulus duration on estimates of human cochlear tuning.

Auditory masking methods originally employed to assess behavioral frequency selectivity have evolved over the years to infer cochlear tuning. Behavioral forward masking thresholds for spectrally notched noise maskers and a fixed, low-level probe tone provide accurate estimates of cochlear tuning. Here, we use this method to investigate the effect of stimulus duration on human cochlear tuning at 500 Hz and 4 kHz. Probes were 20-ms sinusoids at 10 dB sensation level. Maskers were noises with a spectral notch symmetrically and asymmetrically placed around the probe frequency. For seven participants with normal hearing, masker levels at masking threshold were measured in forward masking for various notch widths and for masker durations of 30 and 400 ms. Measurements were fitted assuming rounded exponential filter shapes and the power spectrum model of masking, and equivalent rectangular bandwidths (ERBs) were inferred from the fits. At 4 kHz, masker thresholds were higher for the shorter maskers but ERBs were not significantly different for the two masker durations (ERB30ms=294 Hz vs. ERB400ms=277 Hz). At 500 Hz, by contrast, notched-noise curves were shallower for the 30-ms than the 400-ms masker, and ERBs were significantly broader for the shorter masker (ERB30ms=126 Hz vs. ERB400ms=55 Hz). We discuss possible factors that may underlay the duration effect at low frequencies and argue that it may not be possible to fully control for those factors. We conclude that tuning estimates are not affected by maker duration at high frequencies but should be measured and interpreted with caution at low frequencies.

Differences in the pupillary responses to evening light between children and adolescents.

BACKGROUND: In the mammalian retina, intrinsically-photosensitive retinal ganglion cells (ipRGC) detect light and integrate signals from rods and cones to drive multiple non-visual functions including circadian entrainment and the pupillary light response (PLR). Non-visual photoreception and consequently non-visual sensitivity to light may change across child development. The PLR represents a quick and reliable method for examining non-visual responses to light in children. The purpose of this study was to assess differences in the PLRs to blue and red stimuli, measured one hour prior to bedtime, between children and adolescents. METHODS: Forty healthy participants (8-9 years, n = 21; 15-16 years, n = 19) completed a PLR assessment 1 h before their habitual bedtime. After a 1 h dim-light adaptation period (< 1 lx), baseline pupil diameter was measured in darkness for 30 s, followed by a 10 s exposure to 3.0 × 1013 photons/cm2/s of either red (627 nm) or blue (459 nm) light, and a 40 s recovery in darkness to assess pupillary re-dilation. Subsequently, participants underwent 7 min of dim-light re-adaptation followed by an exposure to the other light condition. Lights were counterbalanced across participants. RESULTS: Across both age groups, maximum pupil constriction was significantly greater (p < 0.001, ηp2 = 0.48) and more sustained (p < 0.001, ηp2 = 0.41) during exposure to blue compared to red light. For adolescents, the post-illumination pupillary response (PIPR), a hallmark of melanopsin function, was larger after blue compared with red light (p = 0.02, d = 0.60). This difference was not observed in children. Across light exposures, children had larger phasic (p < 0.01, ηp2 = 0.20) and maximal (p < 0.01, ηp2 = 0.22) pupil constrictions compared to adolescents. CONCLUSIONS: Blue light elicited a greater and more sustained pupillary response than red light in children and adolescents. However, the overall amplitude of the rod/cone-driven phasic response was greater in children than in adolescents. Our findings using the PLR highlight a higher sensitivity to evening light in children compared to adolescents, and continued maturation of the human non-visual photoreception/system throughout development.

Effect of muscle length on the modulation of H reflex and inhibitory mechanisms of Ia afferent discharges during passive muscle lengthening.

The effectiveness of activated Ia afferents to discharge ᵯC-motoneurons is decreased during passive muscle lengthening compared with static and shortening muscle conditions. Evidence suggests that these regulations are explained by (1) greater post-activation depression induced by homosynaptic post-activation depression (HPAD) and (2) primary afferent depolarization (PAD). It remains uncertain whether muscle length impacts the muscle lengthening-related aspect of regulation of the effectiveness of activated Ia afferents to discharge ᵯC-motoneurons, HPAD, PAD and heteronymous Ia facilitation (HF). We conducted a study involving 15 healthy young individuals. We recorded conditioned or non-conditioned soleus Hoffmann (H) reflex with electromyography (EMG) to estimate the effectiveness of activated Ia afferents to discharge ᵯC-motoneurons, HPAD, PAD and HF during passive lengthening, shortening and static muscle conditions at short, intermediate and long lengths. Our results show that the decrease of effectiveness of activated Ia afferents to discharge ᵯC-motoneurons and increase of post-activation depression during passive muscle lengthening occur at all muscle lengths. For PAD and HF, we found that longer muscle length increases the magnitude of regulation related to muscle lengthening. To conclude, our findings support an inhibitory effect (resulting from increased post-activation depression) of muscle lengthening and longer muscle length on the effectiveness of activated Ia afferents to discharge α-motoneurons. The increase in post-activation depression associated with muscle lengthening can be attributed to the amplification of Ia afferents discharge.

Pain-induced effects on the pupillary light response under high and low illumination conditions.

Objective: The present study investigated the impact of two different light intensities on the pain-modulated pupillary light response (PLR). Additionally, it aimed to demonstrate parasympathetic and sympathetic influences on PLR parameters in response to pain, as predicted by functional models. Method: A total of 24 participants were included in a randomized, repeated-measures design. The PLR was measured in response to both dark and bright light stimuli within two test cycles. Pain was induced using the cold pressor test (CPT), which involved immersing participants' feet in ice water. PLR measurements were taken during baseline and ice-water immersion within each test cycle. The assessed PLR parameters included initial diameter (INIT), latency (LAT), amplitude (AMP), and re-dilation time (ReDIL25). Along with these parameters, heart rate (HR) and pain ratings were also computed and analyzed. Main results: The CPT caused moderate pain in participants, and the resulting PLR parameters were found to be congruent with the expected parasympathetic and sympathetic nervous system activities. Although the luminance of the stimulus did influence PLR parameters, no interaction with pain exposure was found. Significance: The results showed that different aspects of pain experienced by an individual, as modulated through the sympathetic and parasympathetic nervous systems, are visible in their pupillary reactions to light. Notably, within the range used in the current study, light intensity did not significantly affect the pain-related PLR effects.

Pupillary Light Reflex Detected by Ophthalmic Ultrasonography in Critically Ill Children With Difficult to Assess Pupils.

Direct visualization of the eye can be difficult or impossible when there is significant facial burns, trauma, or edema. We present 4 nonresponsive, critically ill children whose pupils could not be directly visualized. Ophthalmic ultrasound revealed pupillary reactivity at presentation and throughout their recovery. Determining pupillary reactivity in these nonresponsive patients impacted their initial triage, resuscitation, and medical management. We propose that ophthalmic point-of-care ultrasonography can assess the pupillary light reflex in critically ill children whose pupils cannot be directly visualized.

Myogenic artifacts masquerade as neuroplasticity in the auditory frequency-following response.

The frequency-following response (FFR) is an evoked potential that provides a neural index of complex sound encoding in the brain. FFRs have been widely used to characterize speech and music processing, experience-dependent neuroplasticity (e.g., learning and musicianship), and biomarkers for hearing and language-based disorders that distort receptive communication abilities. It is widely assumed that FFRs stem from a mixture of phase-locked neurogenic activity from the brainstem and cortical structures along the hearing neuraxis. In this study, we challenge this prevailing view by demonstrating that upwards of ~50% of the FFR can originate from an unexpected myogenic source: contamination from the postauricular muscle (PAM) vestigial startle reflex. We measured PAM, transient auditory brainstem responses (ABRs), and sustained frequency-following response (FFR) potentials reflecting myogenic (PAM) and neurogenic (ABR/FFR) responses in young, normal-hearing listeners with varying degrees of musical training. We first establish that PAM artifact is present in all ears, varies with electrode proximity to the muscle, and can be experimentally manipulated by directing listeners' eye gaze toward the ear of sound stimulation. We then show this muscular noise easily confounds auditory FFRs, spuriously amplifying responses 3-4-fold with tandem PAM contraction and even explaining putative FFR enhancements observed in highly skilled musicians. Our findings expose a new and unrecognized myogenic source to the FFR that drives its large inter-subject variability and cast doubt on whether changes in the response typically attributed to neuroplasticity/pathology are solely of brain origin.