Review
Neurosciences
Carla R. Lima, Pradeep K. Sahu, Daniel F. Martins, William R. Reed
Summary: This scoping review systematically identified and summarized research findings related to the impact of experimentally-induced pain or noxious stimulation on direct MSA discharge/response. Clinical and pre-clinical studies showed discrepancies in their findings regarding the nociceptive-fusimotor relationship, highlighting the need for further investigative efforts to reconcile these differences and establish or refute the existence of such relationship in muscular pain.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Review
Physiology
Dar'ya Sas, Fanny Gaudel, Dorly Verdier, Arlette Kolta
Summary: The topic of this review is the emergence of ectopic firing in muscle spindle afferents (MSAs) and its potential role in pathological pain. The review highlights the mechanisms underlying the generation of ectopic firing, such as oscillations supported by a persistent sodium current and regulation of extracellular Ca2+ by astrocytes. The review also discusses the possible cross-talk between MSAs and nociceptors in the periphery.
EXPERIMENTAL PHYSIOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Glauce Crivelaro Nascimento, Gabrielle Jacob, Bruna Araujo Milan, Gabrielli Leal-Luiz, Bruno Lima Malzone, Airam Nicole Vivanco-Estela, Daniela Escobar-Espinal, Fernando Jose Dias, Elaine Del-Bel
Summary: The pathophysiologic mechanisms of the lateral pterygoid muscles (LPMs) and the trigeminal system related to Parkinson's Disease (PD)-induced orofacial manifestations were investigated. The study found that hemiparkinsonism increased slow skeletal myosin fibers in the LPMs, while in dyskinetic rats, these fibers decreased in the contralateral side of the lesion. Activation of the spinal trigeminal nucleus may be associated with orofacial sensorial impairment in Parkinsonian rats, while a fatigue profile on LPMs is suggested in L-DOPA-induced dyskinesia when the motor and facial nucleus are activated.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Anesthesiology
Hauke Basedau, Trine Nielsen, Katharina Asmussen, Katrin Gloss, Jan Mehnert, Rigmor H. Jensen, Arne May
Summary: This study investigates the functional relationship between the trigeminal and occipital regions in humans and finds a strong functional interplay between them.
Article
Anesthesiology
Sarasa Tohyama, Matthew R. Walker, Jia Y. Zhang, Joshua C. Cheng, Mojgan Hodaie
Summary: The study utilized diffusion tensor imaging (DTI) to identify microstructural abnormalities in the brainstem trigeminal fibers as a common biomarker of surgical response in trigeminal neuralgia (TN), which may vary across different subtypes of TN. Abnormalities in the affected pontine trigeminal fibers were found to distinguish treatment nonresponders from responders, with the degree of abnormalities associated with the likelihood of surgical response across TN subtypes. This highlights the potential value of DTI as a noninvasive tool for predicting treatment response and understanding differences in TN treatment outcomes.
Article
Neurosciences
Yuya Okutsu, Akihiro Yamada, Sotatsu Tonomura, Ryan J. Vaden, Jianguo G. Gu
Summary: The study characterized the electrophysiological properties of V2 trigeminal A beta-afferent neurons, identifying four different types based on action potential properties, which could be useful for understanding their functions in orofacial regions.
Article
Clinical Neurology
Emily P. Mills, Rahena Akhter, Flavia Di Pietro, Greg M. Murray, Chris C. Peck, Paul M. Macey, Luke A. Henderson
Summary: This study found that individuals with painful temporomandibular disorders (TMD) display altered static and dynamic functional connectivity within the brainstem pain-modulation network, potentially affecting the maintenance of pain.
Review
Clinical Neurology
Rachyl M. Shanker, Miri Kim, Chloe Verducci, Elhaum G. Rezaii, Kerry Steed, Atul Mallik, Douglas E. Anderson
Summary: This systematic review identified trigeminal neuralgia (TN) induced by brainstem infarct as an understudied pathological cause, lacking clear evidence on the most effective interventions. However, it is optimistic that this review will encourage further investigation into the best treatment for these patients.
WORLD NEUROSURGERY
(2021)
Review
Clinical Neurology
Rupert D. Smit, Nikolaos Mouchtouris, KiChang Kang, Maikerly Reyes, Anish Sathe, Sarah Collopy, Giyarpuram Prashant, Hsiangkuo Yuan, James J. Evans
Summary: This literature review examines the evidence for interventional therapies in medically intractable SUNCT/SUNA, including occipital nerve stimulation, pulsed radiofrequency, stereotactic radiosurgery, and microvascular decompression. The review finds promising outcomes with these treatments, but emphasizes the need for further research.
JOURNAL OF NEUROLOGY NEUROSURGERY AND PSYCHIATRY
(2023)
Article
Biochemistry & Molecular Biology
Amalia Callado Perez, Maxime Demers, Arash Fassihi, Jeffrey D. Moore, David Kleinfeld, Martin Deschenes
Summary: The brainstem contains neural circuits that control vital functions' homeostasis, such as breathing depth, rate, and apnea. The reflex for apnea is believed to be mediated by sensory pathways involving vagal and glossopharyngeal afferents, as well as trigeminal afferents from the nasal cavity.
Review
Biochemistry & Molecular Biology
Francesca Bonomini, Gaia Favero, Stefania Castrezzati, Elisa Borsani
Summary: Orofacial pain is a complex biomedical challenge without a satisfactory solution. This review evaluates the involvement of neurotrophins in orofacial nociception and their potential role as targets for pain modulation. Further studies are needed to clarify their application in clinical practice.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Clinical Neurology
Can Sarica, Christian Iorio-Morin, David H. Aguirre-Padilla, Michelle Paff, Samuelle-Arianne Villeneuve, Artur Vetkas, Kazuaki Yamamoto, Nardin Samuel, Vanessa Milano, Aaron Loh, Brendan Santyr, Ajmal Zemmar, Andres M. Lozano, Mojgan Hodaie
Summary: This study systematically reviewed the literature on peripheral nerve field stimulation (PNFS) for trigeminal pain and found that PNFS can provide effective long-term pain control for patients with trigeminal pain.
JOURNAL OF NEUROSURGERY
(2022)
Article
Neurosciences
Valeria Oliva, Rob Gregory, Wendy-Elizabeth Davies, Lee Harrison, Rosalyn Moran, Anthony E. Pickering, Jonathan C. W. Brooks
Summary: Pain can be alleviated by shifting attention elsewhere, and the brainstem regions including locus coeruleus, rostral ventromedial medulla, and periaqueductal grey are involved in attentional analgesia. Functional interactions between these regions and the cortex modulate nociceptive input to reduce pain, particularly in situations requiring conflicting attentional demands.
Article
Clinical Neurology
Per Kristian Eide
Summary: This study examined the occurrence of familial TN among patients with classical or idiopathic TN and found a higher prevalence of familial TN than traditionally assumed.
JOURNAL OF THE NEUROLOGICAL SCIENCES
(2022)
Article
Neurosciences
Ayano Katagiri, Kazuo Tsubota, Lou Mikuzuki, Shigeru Nakamura, Akira Toyofuku, Takafumi Kato, David A. Bereiter, Koichi Iwata
Summary: Repeated application of diquafosol sodium reduces ocular pain in dry eye disease by suppressing peripheral P2Y2 expression. Diquafosol increases tear volume and decreases eyeblink frequency, suggesting its efficacy in relieving dry eye symptoms.
NEUROSCIENCE RESEARCH
(2023)
Article
Clinical Neurology
Tiffani J. Mungoven, Kasia K. Marciszewski, Vaughan G. Macefield, Paul M. Macey, Luke A. Henderson, Noemi Meylakh
Summary: This study found that migraineurs displayed increased activation of the dorsolateral prefrontal cortex (dlPFC) during orofacial heat stimulation, along with reduced connectivity between dlPFC and pain modulatory regions. These findings suggest that the modulation of pain modulatory areas by higher cortical regions may be altered in migraineurs, particularly prior to the onset of a migraine attack.
JOURNAL OF HEADACHE AND PAIN
(2022)
Article
Neurosciences
L. Crawford, E. Mills, N. Meylakh, P. M. Macey, V. G. Macefield, L. A. Henderson
Summary: Pain perception can be modulated by various factors, and individuals show differences in pain ratings and neural circuitry during identical noxious stimulation. Considering variability of baseline pain is important in pain modulatory paradigms, as it affects brain activity and connectivity.
Article
Neurosciences
Sabrina Salberg, Angela Doshen, Glenn R. Yamakawa, Jillian Vinall Miller, Melanie Noel, Luke Henderson, Richelle Mychasiuk
Summary: Persistent postsurgical pain affects 20% of youth, with females experiencing chronic pain more than males. This study investigated the neurobiological changes underlying the transition from acute to persistent pain following surgery in adolescence, finding that injury resulted in persistent pain in both sexes, with females displaying greater sensitivity. Gray matter density changes in specific brain areas were observed, driven by different genders. The study emphasizes the importance of studying both sexes and adolescents to better understand postoperative pain.
Review
Clinical Neurology
Donggyu Rim, Luke A. Henderson, Vaughan G. Macefield
Summary: This study reviews the functional and structural brain changes in healthy aging, hypertension, and atrial fibrillation, noting their potential influence on the autonomic nervous system and cardiovascular control.
CLINICAL AUTONOMIC RESEARCH
(2022)
Article
Neurosciences
Fernando A. Tinoco Mendoza, Timothy E. S. Hughes, Rebecca Robertson, Lewis S. Crawford, Noemi Meylakh, Paul M. Macey, Vaughan G. Macefield, Kevin A. Keay, Luke A. Henderson
Summary: The PAG is a critical region for pain-related responses and shows a crude somatotopy for contextually appropriate behavioral responses. Different regions in the PAG are activated by cutaneous and muscle pain. Using ultra-high field functional magnetic resonance imaging, it was found that the PAG exhibits different signal intensity changes in response to noxious stimuli. This suggests a preserved somatotopic organization in the PAG between animals and humans.
Letter
Respiratory System
Chiara Borrelli, Jens Spiesshoefer, Vaughan Macefield, Alberto Giannoni
EUROPEAN RESPIRATORY JOURNAL
(2022)
Article
Physiology
Vaughan G. G. Macefield, Lyndon J. J. Smith, Lucy Norcliffe-Kaufmann, Jose-Alberto Palma, Horacio Kaufmann
Summary: This review focuses on hereditary sensory and autonomic neuropathy type III (HSAN III).
EXPERIMENTAL PHYSIOLOGY
(2023)
Article
Peripheral Vascular Disease
Gianni Sesa-ashton, Janis M. Nolde, Ida Muente, Revathy Carnagarin, Rebecca Lee, Vaughan G. Macefield, Tye Dawood, Yusuke Sata, Elisabeth A. Lambert, Gavin W. Lambert, Antony Walton, Marcio G. Kiuchi, Murray D. Esler, Markus P. Schlaich
Summary: Long-term follow-up studies on catheter-based renal denervation in patients with resistant hypertension show that the method can still effectively reduce blood pressure and decrease medication usage after nearly 9 years of follow-up, without any adverse effects on renal function.
Article
Neurosciences
Alastair J. Loutit, Heather E. Wheat, Heba Khamis, Richard M. Vickery, Vaughan G. Macefield, Ingvars Birznieks
Summary: Dexterous object manipulation relies on force and torque information from tactile afferents in the fingerpads. We compared how human and monkey afferents encode torque information and found differences in response characteristics. Human afferents showed inferior discrimination capacity compared to monkey afferents possibly due to differences in fingertip tissue compliance and skin friction.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Biology
Lewis S. Crawford, Noemi Meylakh, Paul M. Macey, Vaughan G. Macefield, Kevin A. Keay, Luke A. Henderson
Summary: An fMRI study with 47 participants has discovered that stimulus-independent and stimulus-dependent neural networks centered around the midbrain periaqueductal gray region are responsible for an individual's ability to experience placebo analgesia. The specific neural circuits that regulate placebo analgesic responsiveness are still unknown, but involvement of brainstem pain modulatory regions is considered crucial. This study demonstrates differences in neural circuit connectivity between placebo responders and non-responders, highlighting the importance of altered connections involving the hypothalamus, anterior cingulate cortex, and midbrain periaqueductal gray matter in the placebo analgesic response.
COMMUNICATIONS BIOLOGY
(2023)
Article
Neurosciences
Lewis S. Crawford, Emily P. Mills, A. Peek, Vaughan G. Macefield, Kevin A. Keay, Luke A. Henderson
Summary: Prior experiences, conditioning cues, and expectations of improvement play important roles in placebo analgesia expression, which is mediated by the dorsolateral prefrontal cortex (DLPFC). This study investigated the biochemistry and function of DLPFC in 38 healthy individuals during placebo analgesia. The results showed that the concentration of glutamate in DLPFC was inversely correlated with pain rating variability, and there was altered functional connectivity between DLPFC and the midbrain periaqueductal gray. These findings suggest that DLPFC is involved in formulating stimulus-response relationships during conditioning and translating them into altered cortico-brainstem functional relationships for placebo analgesia expression.
Editorial Material
Neurosciences
Vaughan Macefield
JOURNAL OF PHYSIOLOGY-LONDON
(2023)
Article
Neurosciences
Brendan Mccarthy, Sudipta Datta, Gianni Sesa-Ashton, Rebecca Wong, Luke A. Henderson, Tye Dawood, Vaughan G. Macefield
Summary: This study investigates the modulation of vestibular inputs by electrical stimulation of the dlPFC and finds that concurrent stimulation of the dlPFC and vestibular stimulation can effectively eliminate perceptions of sway and sensations of nausea.
EXPERIMENTAL BRAIN RESEARCH
(2023)
Letter
Clinical Neurology
Gianni Sesa-Ashton, Vaughan G. Macefield
CLINICAL AUTONOMIC RESEARCH
(2023)
Article
Neurosciences
Joe A. Braun, Mariya Patel, Luke A. Henderson, Tye Dawood, Vaughan G. Macefield
Summary: We recently demonstrated that transcranial alternating current stimulation of the dorsolateral prefrontal cortex can modulate muscle sympathetic nerve activity, heart rate, and blood pressure. In this study, we tested the effects of stimulation on the ventromedial prefrontal cortices and found partial entrainment of muscle sympathetic nerve activity, as well as modulation of blood pressure and heart rate. Stimulation of the left ventromedial prefrontal cortices resulted in a significant decrease in mean blood pressure.