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Laterality Effects for Higher Cognitive Processes
Published in Robert Miller, Axonal Conduction Time and Human Cerebral Laterality, 2019
The brain mechanisms upon which the psychological function of short term memory is based are not fully understood. An electrophysiological observation which might be an indication of its underlying biology, (already mentioned in section 8.3.1.5) is that many neurones in the frontal regions of cortex can maintain elevated levels of activity in tasks where there is a delay of several seconds between events. In humans, various anticipatory potentials (such as the “contingent negative variation” (CNV) or the “readiness potential (Bereitschaftspotential)) are recordable with gross scalp electrodes. These probably represent the summed potentials in many of the frontal delay neurones such as are recorded in single unit studies in experimental animals. These anticipatory responses can be maintained throughout the delay between events, even though no overt stimulus is driving them during that period.
Pain
Published in Hilary McClafferty, Mind–Body Medicine in Clinical Practice, 2018
PMR has been shown to be highly efficacious in migraine prevention and has been shown to be as effective as a pharmacological migraine prophylaxis (Nestoriuc and Martin 2007). In a study on the effectiveness of PMR as a preventive treatment, 35 migraine patients and 46 healthy controls were selected and 16 migraineurs and 21 healthy participants underwent the study with the remaining serving as controls. Those in the study received 6-week training in PMR with pre- and post-measures of evoked potentials, contingent negative variation (CNV), which reflects central information processing. CNV has been shown to be altered in migraine patients who show higher amplitudes and reduced habituation—findings that have been shown to be modifiable with some prophylactic migraine treatments such as beta-blockers and behavioral therapy. In this study, the effects of PMR were measured.
The pathophysiology of primary headache
Published in Stephen D. Silberstein, Richard B. Upton, Peter J. Goadsby, Headache in Clinical Practice, 2018
Stephen D. Silberstein, Richard B. Upton, Peter J. Goadsby
Placement of an electrode into the region of the periaqueductal grey matter can evoke a migraine-like headache.167 Cells in the same region can be activated after superior sagittal sinus stimulation.168 Contingent negative variation (CNV), an event-related slow cerebral potential, is increased in amplitude and its habituation is lacking in patients with migraine without aura (Figure 5.13).169–-171 Furthermore, CNV is under aminergic control and normalizes after treatment with beta-blockers.172 The visual evoked potential is augmented rather than habituated in migraine patients when studied between attacks.173 These clinical observations taken together provide important components of the human data that argue that migraine is a disorder of the central nervous system.
Chronic stress and anticipatory event-related potentials: the moderating role of resilience
Published in Stress, 2020
One of the critical cognitive processes involved in successful adaptation to the environment is anticipation, that is, the ability to predict an upcoming event and approach behavior (Brunia, 1999; Knutson & Greer, 2008; Wynn et al., 2010). Previous research has indicated that the prefrontal cortex (PFC), a key region in the regulation of stress, is important for anticipatory behaviors (de Araújo Costa Folha et al., 2017; de Kloet et al., 2019). The contingent negative variation (CNV), sometimes called the expectancy wave, is associated with anticipatory processing and motivation to prepare a subsequent behavioral response (Bekker et al., 2004; Brunia, 1999). Neurophysiological studies have indicated that at least two slow waves are hidden in the CNV: the early wave (CNV1) and the late wave (CNV2). The CNV1 amplitude is thought to reflect neural activities for orienting to the cue and may be related to anticipation of an upcoming stimulus (Mulder et al., 2002; Rohricht et al., 2018), and the CNV2 amplitude is thought to reflect neural activities for motor preparation (Jonkman et al., 2003).
The association between slow cortical potentials preceding antisaccades and disturbances of consciousness in persons with paraphilic sexual behaviour
Published in International Review of Psychiatry, 2019
Anna V. Kirenskaya, Maxim Kamenskov
All three groups differed significantly in the characteristics of the slow cortical potentials. According to previously obtained data (Kirenskaya et al., 2011; Kirenskaya, Kamenskov, Myamlin, Novototsky-Vlasov, & Tkachenko, 2013) the analysis of contingent negative variation (CNV) revealed two distinct stages during the fixation interval. The early stage was represented by a negative wave with the maximal amplitude over the midline fronto-central area (Figure 3). Early bilateral CNV in frontal cortical regions is considered to be a reflection of various cognitive aspects of the preparatory set involved in preparing the system for appropriate task performance, such as sustained attention, preparation to the inhibition of the reflexive saccades, and maintenance of information in working memory. The late stage of CNV was characterized by the expansion of activation to post-central cortical regions with maximal CNV amplitudes at the medial and left parietal sites. Saccadic ERP and fMRI studies have found a parietal activation that was related to the initiation of the saccadic eye movement (Broerse et al., 2001; McDowell et al., 2008).
Predictive factors of success in neurofeedback training for children with ADHD
Published in Developmental Neurorehabilitation, 2019
Yasuko Okumura, Yosuke Kita, Mikimasa Omori, Kota Suzuki, Akira Yasumura, Ayako Fukuda, Masumi Inagaki
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with core symptoms of inattention, hyperactivity, and impulsivity.1,2 ADHD is reported to affect 3–7% of school-age children3 and often has a broad impact on their daily life, academic achievements, and/or social interactions. Behavioral problems in ADHD have been considered to have neurophysiological bases, since children with ADHD frequently exhibit atypical patterns of brain activity. In a resting-state electroencephalogram (EEG), for example, increased theta activity and/or a high theta-to-beta ratio over the fronto-central scalp region has often been found,4,5 which may be associated with underarousal and insufficient task-related cortical activation.6 In some studies using event-related potentials (ERPs), reductions in contingent negative variation (CNV) have indicated decreased attention, anticipation, and/or preparation for upcoming events in ADHD.7 These observations support the notion that ADHD symptoms are associated with dysfunctional brain activities.