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Psychosocial Aspects of Diabetes
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
Underlying mechanisms of panic attacks or panic disorder involve the hippocampus, anterior cingulate cortex, insula, amygdala, lateral prefrontal cortex, and periaqueductal gray matter. In a panic attack, there is usually elevated blood flow or metabolism. Insula hyperactivity is likely related to irregular norepinephrine activity. The periaqueductal gray matter is implicated in generating fear responses. There is an abnormally functioning “brain circuit” made up of the amygdala, central gray matter, ventromedial nucleus of the hypothalamus, and locus coeruleus. Often, there are lower than normal levels of gamma-aminobutyric acid (GABA). Hyperventilation is a component of panic, and results in the exhalation of excessive carbon dioxide. There may be a feeling of being unable to “catch their breath.” The partial pressure of carbon dioxide is another mediator of panic disorder. Panic attacks may begin and worsen in association with diabetes progressing, increased complications, and loss of normal functioning. They are also accompany with depression in many patients.
Anatomy of the head and neck
Published in Helen Whitwell, Christopher Milroy, Daniel du Plessis, Forensic Neuropathology, 2021
The cerebral aqueduct traverses the length of the midbrain ventral to the colliculi, with the trochlear and oculomotor cranial nerve nuclei located adjacent to it within the periaqueductal grey matter. At the level of the inferior colliculus, the superior cerebellar peduncles are related to the central portion of the tegmentum. Ventrally, the midbrain tegmentum is the site of the substantia nigra, consisting in part of pigmented, melanin-containing neurons that synthesise dopamine as their transmitter. It is degeneration of the substantia nigra that is associated with Parkinson's disease and problems secondary to drug abuse. Anterior to the substantia nigra are the large crus cerebri, composed entirely of the descending cortical efferent fibres that have passed through the internal capsule after leaving the cerebral hemispheres. Sections through the brainstem are illustrated in Figure 1.9a–e.
Quality of life affected by endometriosis: Lifestyle modification for symptom alleviation
Published in Seema Chopra, Endometriosis, 2020
Exercise has been shown to activate endogenous analgesia in healthy individuals and thereby an increased pain threshold due to the release of endogenous opioid and activation of (supra) spinal nociceptive inhibitory mechanisms mediated by the brain. Release of beta-endorphins from the pituitary (peripherally) and the hypothalamus (centrally) is triggered by exercise which in turn enables analgesic effects by activating μ-opioid receptors peripherally and centrally. Through its projections on the periaqueductal gray matter, the hypothalamus has the capacity to activate descending nociceptive inhibitory mechanisms. Some patients with chronic pain show dysfunctional response of and aberrations in central pain modulation to exercise; therefore, exercise should be individually tailored for prevention of symptom flares [21]. As was demonstrated in this study, analgesics could be less effective for pain relief in women with endometriosis who exercise regularly [13].
Effectiveness of spinal mobilization and postural correction exercises in the management of cervicogenic headache: A randomized controlled trial
Published in Physiotherapy Theory and Practice, 2023
The present study suggests that SM is effective in the management of patient with CGH. The primary cause of CGH is the impairment in the cervical spine especially the upper cervical spine (C1-C3) (Govind and Bogduk, 2021). SM technique was used for upper cervical segments. Upper cervical translatoric glide was applied for the C1 vertebra. We found only one published randomized controlled trial investigating the effect of upper cervical translatoric glide in patients suffering from CGH. This study assessed the immediate effects of SM on CGH (Malo-Urries et al., 2017). The possible mechanism behind the positive effect could be the activation of descending pain inhibition system via corticospinal projections from the periaqueductal gray matter (Wright, 1995).
Pro-nociceptive pain modulation profile in patients with acute and chronic shoulder pain: a hypothesis-generating topical review
Published in Physical Therapy Reviews, 2021
Rani Othman, Nicola Swain, Steve Tumilty, Prasath Jayakaran, Ramakrishnan Mani
Descending control mechanisms that influence the neuronal activity of the dorsal horn arises from several supra-spinal sites [61]. In particular, periaqueductal grey matter and nuclei of the rostral ventral medulla are the key midbrain structures that are interconnected with the higher brain centres and limbic areas, and they receive direct inputs from the spinomesencephalic tract [52, 59, 61, 62]. The periaqueductal grey matter project to rostral ventral medulla, which projects onto the dorsal horn of the spinal cord [61]. The descending facilitatory or inhibitory control mechanisms of the periaqueductal grey matter and rostral ventral medulla are mainly coordinated by the activities of the higher brain centres [52, 62]. One aspect of descending control is associated with diffuse noxious inhibitory controls [59, 61]. Diffuse noxious inhibitory controls is a phenomenon that refers to a reduction in the nociceptive inputs produced by supra-spinally generated inhibition of wide dynamic range neurons and nociceptive-specific neurons in the dorsal horn of the spinal cord [63–65]. On the contrary, it is also evident that periaqueductal grey matter and rostral ventral medulla projections can facilitate nociceptive inputs at the dorsal horn of the spinal cord [52, 61]. Evidence suggests that descending facilitation of spinal nociception is a major contributor to the development of central sensitization, a key contributing mechanism linked to the chronic pain experience [52, 61].
Medication overuse headache: an overview of clinical aspects, mechanisms, and treatments
Published in Expert Review of Neurotherapeutics, 2020
Abouch V. Krymchantowski, Carla C. Jevoux, Ana G. Krymchantowski, Rodrigo Salvador Vivas, Raimundo Silva-Néto
MOH patients have less gray matter volume in the left middle occipital gyrus and in the orbital frontal cortex in comparison with chronic migraineurs without medication overuse [42]. The anterior cingulate cortex, the insula, the precuneus, left amygdala, and left hippocampus have also less gray matter volume in MOH patients [40]. On the other hand, areas of pain modulation as the periaqueductal gray matter, thalamus and ventral striatum as well as the left temporal pole reveal increased volumes. The meaning of these differences is still controversial, but MOH is indeed associated with dysfunction of modulating and pain processing regions additionally to nuclei involved in rewarding circuits, which is not known yet whether it possesses a causal relationship with the development of MOH [10,42].