Massieh Moayedi

University College London | UCL · Department of Neuroscience, Physiology, and Pharmacology

Peripheral magnetic stimulation is a potentially promising modality to help manage postoperative pain. We systematically reviewed the effect of peripheral magnetic stimulation on acute and chronic postoperative pain. MEDLINE, Cochrane CENTRAL, EMBASE, ProQuest Dissertations, and ClinicalTrials.gov were searched from inception until May 2021. We inc...

Although recent studies support significant differences in intrinsic structure, function, and connectivity along the longitudinal axis of the hippocampus, few studies have investigated the normative development of this dimension. In addition, factors known to influence hippocampal structure, such as sex or puberty, have yet to be characterized when...

Aims Repetitive peripheral magnetic stimulation (rPMS) is a novel non-pharmacological treatment modality. This non-invasive approach can stimulate peripheral nerves to provide analgesia through neuromodulation. We report the first case of ultrasound-guided rPMS to treat a case of severe refractory glossopharyngeal neuralgia. Methods A 70-year-old...

Objectives: The purpose of this study was to develop protocols that optimize patient radiation dose and image quality for cone beam computed tomographic (CBCT) sialography for the major salivary glands. Study design: Radiation absorbed dose measurements were repeated in triplicate using 25 sites in the head and neck of a Radiation ANalog DOsimet...

The neuroanatomical circuitry of jaw muscles has been mostly explored in non-human animals. A recent rodent study revealed a novel circuit from the central amygdala (CeA) to the trigeminal motor nucleus (5M), which controls biting attacks. This circuit has yet to be delineated in humans. Ultra-high diffusion-weighted imaging data from the Human Con...

Background There is evidence of altered corticolimbic circuitry in adults with chronic pain, but relatively little is known of functional brain mechanisms in adolescents with neuropathic pain (NeuP). Pediatric NeuP is etiologically and phenotypically different from NeuP in adults, highlighting the need for pediatric-focused research. The amygdala i...

Chronic multisite musculoskeletal pain (CMP) is common and highly morbid. However, vulnerability factors for CMP are poorly understood. Previous studies have independently shown that both small hippocampal brain volume and genetic risk alleles in a key stress system gene, FKBP5, increase vulnerability for chronic pain. However, little is known rega...

Chronic pain patients frequently report memory and concentration difficulties. Objective testing in this population points to poor performance on memory and cognitive tests, and increased comorbid anxiety and depression. Recent evidence has suggested convergence between chronic pain and memory deficits onto the hippocampus. The hippocampus consists...

How we perceive our bodies is fundamental to our self-consciousness and our experience in the world. There are two types of interrelated internal body representations-a subjective experience of the position of a limb in space (body schema) and the subjective experience of the shape and size of the limb (body image). Body schema has been extensively...

Introduction Artifact Reduction (AR) software has been incorporated into some Cone-Beam Computed Tomography (CBCT) systems to reduce the severity of beam hardening (BH) artifacts, and improve image quality. This study quantifies BH artifact and evaluates the effectiveness of AR in two CBCT systems. Methods Palatal roots of Dent-Alike™ (Dentsply Si...

Pain is a subjective experience with significant individual differences. Laboratory studies investigating pain thresholds and experimental acute pain have identified structural and functional neural correlates. However, these types of pain stimuli have limited ecological validity to real-life pain experiences. Here, we use an orthodontic procedure-...

Objective: In this experimental study, we aimed to determine whether guided music listening (GML) - a music intervention based on models of mood mediation and attention modulation - modulates masticatory muscle activity and awake bruxism in subjects with chronic painful muscular temporomandibular disorders (TMD myalgia, mTMD), a condition causing...

How we perceive our bodies is fundamental to our self-consciousness and our experience in the world. There are two types interrelated internal body representations; a subjective experience of the position of a limb in space (body schema) and the subjective experience of the shape and size of the limb (body image). Body schema has been extensively s...

Pain is a subjective experience with significant individual differences. Laboratory studies investigating pain thresholds and acute pain have identified structural and functional neural correlates. However, these types of pain stimuli have limited ecological validity to real-life pain experience. Here, we use an orthodontic procedure which typicall...

Nervous systems exploit regularities in the sensory environment to predict sensory input, adjust behavior, and thereby maximize fitness. Entrainment of neural oscillations allows retaining temporal regularities of sensory information, a prerequisite for prediction. Entrainment has been extensively described at the frequencies of periodic inputs mos...

Some forms of chronic pain are thought to be driven and maintained by nociceptive input, which can drive plasticity within nociceptive pathways. We have previously identified abnormalities along the entire nociceptive pathway in chronic myalgic temporomandibular disorders (mTMD), including the trigeminal nerves, brainstem pathways, and in the thala...

Nervous systems exploit regularities in the sensory environment to predict sensory input and adjust behavior, and thereby maximize fitness. Entrainment of neural oscillations allows retaining temporal regularities of sensory information, a prerequisite for prediction. Entrainment has been extensively described at the frequencies of periodic inputs...

Abstract Recent neuroimaging studies implicate the medial temporal lobe (MTL) in nociception and pain modulation. Here, we aim to identify which subregions of the MTL are involved in human pain and to test its connectivity in a cohort of chronic low back pain patients (CBP). We conducted two coordinate-based meta-analyses to determine which regions...

Chronic orofacial pain (COFP) disorders are prevalent and debilitating pain conditions affecting the head, neck and face areas. Neuroimaging studies have reported functional and grey matter abnormalities, but not all the studies have reported consistent findings. Identifying convergent abnormalities across COFPs provides a basis for future hypothes...

Human pain neuroimaging has exploded in the past 2 decades. During this time, the broader neuroimaging community has continued to investigate and refine methods. Another key to progress is exchange with clinicians and pain scientists working with other model systems and approaches. These collaborative efforts require that non-imagers be able to eva...

Background Approximately 30% of patients with major depressive disorder suffer treatment non-responsive depression (TNRD); novel interventions targeting the substrates of illness this population are desperately needed. Convergent evidence from lesion, stimulation, connectivity, and functional neuroimaging studies implicate the frontopolar cortex (F...

The dorsolateral prefrontal cortex (DLPFC) is a functionally and structurally heterogeneous region and a key node of several brain networks, implicated in cognitive, affective, and sensory processing. As such, the DLPFC is commonly activated in experimental pain studies, and shows abnormally increased function in chronic pain populations. Furthermo...

Tooth loss is associated with altered sensory, motor, cognitive and emotional functions. These changes vary highly in the population and are accompanied by structural and functional changes in brain regions mediating these functions. It is unclear to what extent this variability in behavior and function is caused by genetic and/or environmental det...

Migraine is a pain disorder associated with abnormal brain structure and function, yet the effect of migraine on acute pain processing remains unclear. It also remains unclear whether altered pain-related brain responses and related structural changes are associated with clinical migraine characteristics. Using fMRI and three levels of thermal stim...

Feature selection has been extensively studied in the context of goal-directed behavior, where it is heavily driven by top-down factors. A more primitive version of this function is the detection of bottom-up changes in stimulus features in the environment. Indeed, the nervous system is tuned to detect fast-rising, intense stimuli that are likely t...

Early debate on pain processing focused on whether pain was the product of specific receptors in the periphery. The discovery of nociceptors and the variety of modalities of dangerous stimuli they can process have largely convinced the pain community that specificity exists at least at the level of primary afferents. Nevertheless, nociception does...

Supporting Information

Ongoing fluctuations of intrinsic cortical networks determine the dynamic state of the brain, and influence the perception of forthcoming sensory inputs. The functional state of these networks is defined by the amplitude and phase of ongoing oscillations of neuronal populations at different frequencies. The contribution of functionally different co...

Pedophilia is a principal motivator of child molestation, incurring great emotional and financial burdens on victims and society. Even among pedophiles who never commit any offense, the condition requires lifelong suppression and control. Previous comparison using voxel-based morphometry (VBM) of MR images from a large sample of pedophiles and cont...

The vertex potential is the largest response that can be recorded in the electroencephalogram of an awake, healthy human. It is elicited by sudden and intense stimuli, and is composed by a negative-positive deflection. The stimulus properties that determine the vertex potential amplitude have been well characterized. Nonetheless, its functional sig...

Recent research suggests the anterior and posterior hippocampus form part of two distinct functional neural networks. Here we investigate the structural underpinnings of this functional connectivity difference using diffusion-weighted imaging-based parcellation. Using this technique, we substantiated that the hippocampus can be parcellated into dis...

The frontal pole corresponds to Brodmann area (BA) 10, the largest single architectonic area in the human frontal lobe. Generally, BA10 is thought to contain two or three subregions that subserve broad functions such as multitasking, social cognition, attention, and episodic memory. However, there is a substantial debate about the functional and st...

Rumination is a form of thought characterized by repetitive focus on discomforting emotions or stimuli. In chronic pain disorders, rumination can impede treatment efficacy. The brain mechanisms underlying rumination about chronic pain are not understood. Interestingly, a link between rumination and functional connectivity (FC) of the brain's defaul...

Repeated exposure to pain can result in sensitization of the central nervous system enhancing subsequent pain and potentially leading to chronicity. The ability to reverse this sensitization in a top-down manner would be of tremendous clinical benefit but the degree that this can be accomplished volitionally remains unknown. Here we investigated wh...

Physical pain can be clearly distinguished from other states of distress. In recent years, however, the notion that social distress is experienced as physically painful has permeated the scientific literature and popular media. This conclusion is based on the overlap of brain regions that respond to nociceptive input and sociocultural distress. Her...

Idiopathic trigeminal neuralgia (TN) is characterized by paroxysms of severe facial pain but without the major sensory loss that commonly accompanies neuropathic pain. Since neurovascular compression of the trigeminal nerve root entry zone does not fully explain the pathogenesis of TN, we determined whether there were brain gray matter abnormalitie...

Moayedi M, Davis KD. Theories of pain: from specificity to gate control. J Neurophysiol 109: 5-12, 2013. First published October 3, 2012; doi:10.1152/jn.00457.2012.-Several theoretical frameworks have been proposed to explain the physiological basis of pain, although none yet completely accounts for all aspects of pain perception. Here, we provide...

MR-based brain imaging technologies provide a suite of functional and structural metrics that can be used to test hypotheses about the CNS mechanisms underlying pain perception and chronification, from a cellular level to a systems level. Two types of functional MRI discussed in this review provide insight into pain mechanisms: stimulus-evoked fMRI...

Temporomandibular disorder (TMD) is a prevalent chronic pain disorder that remains poorly understood. Recent imaging studies reported functional and gray matter abnormalities in brain areas implicated in sensorimotor, modulatory, and cognitive function in TMD, but it is not known whether there are white matter (WM) abnormalities along the trigemina...

The temporoparietal junction (TPJ) is a key node in the brain's ventral attention network (VAN) that is involved in spatial awareness and detection of salient sensory stimuli, including pain. The anatomical basis of this network's right-lateralized organization is poorly understood. Here we used diffusion-weighted MRI and probabilistic tractography...

It is well established that there is individual variability in pain and temperature sensitivity. Functional brain imaging studies have found that interindividual heat pain variability correlates with brain activity in sensory and pain modulation areas. Thus, it is possible that these individual differences are associated with variability in gray ma...

Widespread brain gray matter (GM) atrophy is a normal part of the aging process. However, recent studies indicate that age-related GM changes are not uniform across the brain and may vary according to health status. Therefore the aims of this study were to determine whether chronic pain in temporomandibular disorder (TMD) is associated with abnorma...

Several studies have investigated various chronic pain populations for structural brain abnormalities in gray matter (GM). Most studies report decreases in GM volume and/or thickness in regions related to antinociceptive, cognitive, and/or limbic functions ([May, 2011][1]). Conversely, some of these

Cortical plasticity is thought to occur following continuous barrage of nociceptive afferent signals to the brain. Hence, chronic pain is presumed to induce anatomical and physiological changes in the brain over time. Inherent factors, some pre-dating the onset of chronic pain, may also contribute to brain abnormalities present in patients. In this...

Patients with temporomandibular disorder (TMD) perform poorly in neuropsychological tests of cognitive function. These deficits might be related to dysfunction in brain networks that support pain and cognition, due to the impact of chronic pain and its related emotional processes on cognitive ability. We therefore tested whether patients with TMD p...

Variability in human behavior related to sex is supported by neuroimaging studies showing differences in brain activation patterns during cognitive task performance. An emerging field is examining the human connectome, including networks of brain regions that are not only temporally-correlated during different task conditions, but also networks tha...

The perception of all sensations includes some sort of magnitude estimate used to calibrate behavior. However, it is not known whether unique intensity coding mechanisms exist for specific modalities or whether a common, centralized magnitude estimator operates for all sensations. Here, we discuss findings regarding pain intensity coding and the ro...