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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38850214

RESUMO

States of consciousness are likely mediated by multiple parallel yet interacting cortico-subcortical recurrent networks. Although the mesocircuit model has implicated the pallidocortical circuit as one such network, this circuit has not been extensively evaluated to identify network-level electrophysiological changes related to loss of consciousness (LOC). We characterize changes in the mesocircuit in awake versus propofol-induced LOC in humans by directly simultaneously recording from sensorimotor cortices (S1/M1) and globus pallidus interna and externa (GPi/GPe) in 12 patients with Parkinson disease undergoing deep brain stimulator implantation. Propofol-induced LOC is associated with increases in local power up to 20 Hz in GPi, 35 Hz in GPe, and 100 Hz in S1/M1. LOC is likewise marked by increased pallidocortical alpha synchrony across all nodes, with increased alpha/low beta Granger causal (GC) flow from GPe to all other nodes. In contrast, LOC is associated with decreased network-wide beta coupling and beta GC from M1 to the rest of the network. Results implicate an important and possibly central role of GPe in mediating LOC-related increases in alpha power, supporting a significant role of the GPe in modulating cortico-subcortical circuits for consciousness. Simultaneous LOC-related suppression of beta synchrony highlights that distinct oscillatory frequencies act independently, conveying unique network activity.


Assuntos
Ritmo alfa , Globo Pálido , Propofol , Inconsciência , Humanos , Propofol/farmacologia , Globo Pálido/efeitos dos fármacos , Globo Pálido/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Inconsciência/induzido quimicamente , Inconsciência/fisiopatologia , Ritmo alfa/efeitos dos fármacos , Ritmo alfa/fisiologia , Idoso , Doença de Parkinson/fisiopatologia , Estimulação Encefálica Profunda/métodos , Anestésicos Intravenosos/farmacologia , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Eletroencefalografia
2.
Prog Neurobiol ; 236: 102613, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631480

RESUMO

While medial frontal cortex (MFC) and subthalamic nucleus (STN) have been implicated in conflict monitoring and action inhibition, respectively, an integrated understanding of the spatiotemporal and spectral interaction of these nodes and how they interact with motor cortex (M1) to definitively modify motor behavior during conflict is lacking. We recorded neural signals intracranially across presupplementary motor area (preSMA), M1, STN, and globus pallidus internus (GPi), during a flanker task in 20 patients undergoing deep brain stimulation implantation surgery for Parkinson disease or dystonia. Conflict is associated with sequential and causal increases in local theta power from preSMA to STN to M1 with movement delays directly correlated with increased STN theta power, indicating preSMA is the MFC locus that monitors conflict and signals STN to implement a 'break.' Transmission of theta from STN-to-M1 subsequently results in a transient increase in M1-to-GPi beta flow immediately prior to movement, modulating the motor network to actuate the conflict-related action inhibition (i.e., delayed response). Action regulation during conflict relies on two distinct circuits, the conflict-related theta and movement-related beta networks, that are separated spatially, spectrally, and temporally, but which interact dynamically to mediate motor performance, highlighting complex parallel yet interacting networks regulating movement.


Assuntos
Conflito Psicológico , Estimulação Encefálica Profunda , Córtex Motor , Doença de Parkinson , Córtex Pré-Frontal , Núcleo Subtalâmico , Ritmo Teta , Humanos , Ritmo Teta/fisiologia , Núcleo Subtalâmico/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Córtex Pré-Frontal/fisiologia , Córtex Motor/fisiologia , Doença de Parkinson/fisiopatologia , Idoso , Vias Neurais/fisiologia , Distonia/fisiopatologia
3.
Eur J Dent Educ ; 27(4): 928-940, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36519508

RESUMO

INTRODUCTION: Competency frameworks have been used to accurately guide the training and assessment of professionals. Dental Public Health professionals require a variety of skills beyond clinical aspects to meet ongoing social, economic, epidemiologic, technological, etc. developments. The purpose of this study was to develop a primary competency framework for dental public health (DPH) professionals by reviewing existing documents that can be modified by authorities based on their needs. MATERIALS AND METHODS: To identify DPH competencies, first a literature review of current postgraduate DPH competencies was conducted in PubMed, Scopus, Google Scholar, and Google from May to June 2021. All English language documents addressing DPH competencies were included and transferred to MAXQDA software. Next, DPH competency domains were extracted and defined, using Clarke and Braun's six-step qualitative thematic analysis method. RESULTS: In total, 206 English documents were retrieved. After exclusion of 201 documents due to being duplicate or not related in screening stages, five full-text English documents describing competencies of DPH specialists from the United Kingdom, the United States, Australia and New Zealand, Canada, and Ireland were reviewed. Thematic analysis led to the provision of a framework consisting of all mentioned competencies in the reviewed documents including nine domains in education, research, management, policy, communication, leadership, professionalism, oral health status, and oral health services. CONCLUSION: The proposed primary framework covers all competency domains and, as a comprehensive tool, can be used as a guide by local, national, and international authorities to develop their own frameworks for training and evaluating the DPH workforce.


Assuntos
Educação em Odontologia , Saúde Pública , Humanos , Estados Unidos , Competência Clínica , Currículo , Reino Unido
4.
PLoS Comput Biol ; 18(11): e1010111, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36395336

RESUMO

Surviving in an uncertain environment requires not only the ability to select the best action, but also the flexibility to withhold inappropriate actions when the environmental conditions change. Although selecting and withholding actions have been extensively studied in both human and animals, there is still lack of consensus on the mechanism underlying these action regulation functions, and more importantly, how they inter-relate. A critical gap impeding progress is the lack of a computational theory that will integrate the mechanisms of action regulation into a unified framework. The current study aims to advance our understanding by developing a neurodynamical computational theory that models the mechanism of action regulation that involves suppressing responses, and predicts how disruption of this mechanism can lead to motor deficits in Parkinson's disease (PD) patients. We tested the model predictions in neurotypical individuals and PD patients in three behavioral tasks that involve free action selection between two opposed directions, action selection in the presence of conflicting information and abandoning an ongoing action when a stop signal is presented. Our results and theory suggest an integrated mechanism of action regulation that affects both action initiation and inhibition. When this mechanism is disrupted, motor behavior is affected, leading to longer reaction times and higher error rates in action inhibition.


Assuntos
Doença de Parkinson , Animais , Humanos , Inibição Psicológica , Cognição , Consenso , Tempo de Reação
5.
J Neural Eng ; 19(4)2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35790135

RESUMO

Objective.Therapeutic efficacy of deep brain stimulation (DBS) in both established and emerging indications, is highly dependent on accurate lead placement and optimized clinical programming. The latter relies on clinicians' experience to search among available sets of stimulation parameters and can be limited by the time constraints of clinical practice. Recent innovations in device technology have expanded the number of possible electrode configurations and parameter sets available to clinicians, amplifying the challenge of time constraints. We hypothesize that patient specific neuroimaging data can effectively assist the clinical programming using automated algorithms.Approach.This paper introduces the DBS Illumina 3D algorithm as a tool which uses patient-specific imaging to find stimulation settings that optimizes activating a target area while minimizing the stimulation of areas outside the target that could result in unknown or undesired side effects. This approach utilizes preoperative neuroimaging data paired with the postoperative reconstruction of the lead trajectory to search the available stimulation space and identify optimized stimulation parameters. We describe the application of this algorithm in three patients with treatment-resistant depression who underwent bilateral implantation of DBS in subcallosal cingulate cortex and ventral capsule/ventral striatum using tractography optimized targeting with an imaging defined target previously described.Main results.Compared to the stimulation settings selected by the clinicians (informed by anatomy), stimulation settings produced by the algorithm that achieved similar or greater target coverage, produced a significantly smaller stimulation area that spilled outside the target (P= 0.002).Significance. The DBS Illumina 3D algorithm is seamlessly integrated with the clinician programmer software and effectively and rapidly assists clinicians with the analysis of image based anatomy, and provides a starting point to search the highly complex stimulation parameter space and arrive at the stimulation settings that optimize activating a target area.


Assuntos
Estimulação Encefálica Profunda , Algoritmos , Estimulação Encefálica Profunda/métodos , Humanos , Neuroimagem , Software
6.
Brain Stimul ; 15(3): 554-565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35292403

RESUMO

BACKGROUND: The efficacy of psychiatric DBS is thought to be driven by the connectivity of stimulation targets with mood-relevant fronto-temporal networks, which is typically evaluated using diffusion-weighted tractography. OBJECTIVE: Leverage intracranial electrophysiology recordings to better predict the circuit-wide effects of neuromodulation to white matter targets. We hypothesize strong convergence between tractography-predicted structural connectivity and stimulation-induced electrophysiological responses. METHODS: Evoked potentials were elicited by single-pulse stimulation to two common DBS targets for treatment-resistant depression - the subcallosal cingulate (SCC) and ventral capsule/ventral striatum (VCVS) - in two patients undergoing DBS with stereo-electroencephalographic (sEEG) monitoring. Evoked potentials were compared with predicted structural connectivity between DBS leads and sEEG contacts using probabilistic, patient-specific diffusion-weighted tractography. RESULTS: Evoked potentials and tractography showed strong convergence in both patients in orbitofrontal, ventromedial prefrontal, and lateral prefrontal cortices for both SCC and VCVS stimulation targets. Low convergence was found in anterior cingulate (ACC), where tractography predicted structural connectivity from SCC targets but produced no evoked potentials during SCC stimulation. Further, tractography predicted no connectivity to ACC from VCVS targets, but VCVS stimulation produced robust evoked potentials. CONCLUSION: The two connectivity methods showed significant convergence, but important differences emerged with respect to the ability of tractography to predict electrophysiological connectivity between SCC and VCVS to regions of the mood-related network. This multimodal approach raises intriguing implications for the use of tractography in surgical targeting and provides new data to enhance our understanding of the network-wide effects of neuromodulation.


Assuntos
Estimulação Encefálica Profunda , Transtorno Depressivo Resistente a Tratamento , Substância Branca , Estimulação Encefálica Profunda/métodos , Transtorno Depressivo Resistente a Tratamento/terapia , Imagem de Tensor de Difusão/métodos , Giro do Cíngulo/fisiologia , Humanos , Substância Branca/fisiologia
7.
Front Hum Neurosci ; 16: 1084782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36819295

RESUMO

The deep brain stimulation (DBS) Think Tank X was held on August 17-19, 2022 in Orlando FL. The session organizers and moderators were all women with the theme women in neuromodulation. Dr. Helen Mayberg from Mt. Sinai, NY was the keynote speaker. She discussed milestones and her experiences in developing depression DBS. The DBS Think Tank was founded in 2012 and provides an open platform where clinicians, engineers and researchers (from industry and academia) can freely discuss current and emerging DBS technologies as well as the logistical and ethical issues facing the field. The consensus among the DBS Think Tank X speakers was that DBS has continued to expand in scope however several indications have reached the "trough of disillusionment." DBS for depression was considered as "re-emerging" and approaching a slope of enlightenment. DBS for depression will soon re-enter clinical trials. The group estimated that globally more than 244,000 DBS devices have been implanted for neurological and neuropsychiatric disorders. This year's meeting was focused on advances in the following areas: neuromodulation in Europe, Asia, and Australia; cutting-edge technologies, closed loop DBS, DBS tele-health, neuroethics, lesion therapy, interventional psychiatry, and adaptive DBS.

9.
Front Hum Neurosci ; 15: 644593, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953663

RESUMO

We estimate that 208,000 deep brain stimulation (DBS) devices have been implanted to address neurological and neuropsychiatric disorders worldwide. DBS Think Tank presenters pooled data and determined that DBS expanded in its scope and has been applied to multiple brain disorders in an effort to modulate neural circuitry. The DBS Think Tank was founded in 2012 providing a space where clinicians, engineers, researchers from industry and academia discuss current and emerging DBS technologies and logistical and ethical issues facing the field. The emphasis is on cutting edge research and collaboration aimed to advance the DBS field. The Eighth Annual DBS Think Tank was held virtually on September 1 and 2, 2020 (Zoom Video Communications) due to restrictions related to the COVID-19 pandemic. The meeting focused on advances in: (1) optogenetics as a tool for comprehending neurobiology of diseases and on optogenetically-inspired DBS, (2) cutting edge of emerging DBS technologies, (3) ethical issues affecting DBS research and access to care, (4) neuromodulatory approaches for depression, (5) advancing novel hardware, software and imaging methodologies, (6) use of neurophysiological signals in adaptive neurostimulation, and (7) use of more advanced technologies to improve DBS clinical outcomes. There were 178 attendees who participated in a DBS Think Tank survey, which revealed the expansion of DBS into several indications such as obesity, post-traumatic stress disorder, addiction and Alzheimer's disease. This proceedings summarizes the advances discussed at the Eighth Annual DBS Think Tank.

10.
Clin Neurophysiol ; 132(8): 1990-2001, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33980469

RESUMO

OBJECTIVE: Suppression of local and network alpha and beta oscillations in the human basal ganglia-thalamocortical (BGTC) circuit is a prominent feature of movement, including suppression of local alpha/beta power, cross-region beta phase coupling, and cortical and subcortical phase-amplitude coupling (PAC). We hypothesized that network-level coupling is more directly related to movement execution than local power changes, given the role of pathological network hypersynchrony in movement disorders such as Parkinson disease (PD). Understanding the specificity of these movement-related signals is important for designing novel therapeutics. METHODS: We recorded globus pallidus internus (GPi) and motor cortical local field potentials during movement execution, passive movement observation and rest in 12 patients with PD undergoing deep brain stimulator implantation. RESULTS: Local alpha/beta power is suppressed in the globus pallidus and motor cortex during both action execution and action observation, although less so during action observation. In contrast, pallidocortical phase synchrony and GPi and motor cortical alpha/beta-gamma PAC are suppressed only during action execution. CONCLUSIONS: The functional dissociation across tasks in pallidocortical network activity suggests a particularly important role of network coupling in motor execution. SIGNIFICANCE: Network level recordings provide important specificity in differentiating motor behavior and may provide significant value for future closed loop therapies.


Assuntos
Ritmo beta/fisiologia , Globo Pálido/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Doença de Parkinson/fisiopatologia , Percepção Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estimulação Encefálica Profunda/métodos , Eletrocorticografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia
11.
Neuron ; 109(5): 869-881.e6, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33482087

RESUMO

The subthalamic nucleus (STN) supports action selection by inhibiting all motor programs except the desired one. Recent evidence suggests that STN can also cancel an already selected action when goals change, a key aspect of cognitive control. However, there is little neurophysiological evidence for dissociation between selecting and cancelling actions in the human STN. We recorded single neurons in the STN of humans performing a stop-signal task. Movement-related neurons suppressed their activity during successful stopping, whereas stop-signal neurons activated at low-latencies near the stop-signal reaction time. In contrast, STN and motor-cortical beta-bursting occurred only later in the stopping process. Task-related neuronal properties varied by recording location from dorsolateral movement to ventromedial stop-signal tuning. Therefore, action selection and cancellation coexist in STN but are anatomically segregated. These results show that human ventromedial STN neurons carry fast stop-related signals suitable for implementing cognitive control.


Assuntos
Inibição Psicológica , Movimento , Neurônios/fisiologia , Desempenho Psicomotor/fisiologia , Núcleo Subtalâmico/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação
12.
Front Syst Neurosci ; 14: 54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32792918

RESUMO

BACKGROUND: Parkinson disease (PD) patients have difficulty with self-initiated (SI) movements, presumably related to basal ganglia thalamocortical (BGTC) circuit dysfunction, while showing less impairment with externally cued (EC) movements. OBJECTIVES: We investigate the role of BGTC in movement initiation and the neural underpinning of impaired SI compared to EC movements in PD using multifocal intracranial recordings and correlating signals with symptom severity. METHODS: We compared time-resolved neural activities within and between globus pallidus internus (GPi) and motor cortex during between SI and EC movements recorded invasively in 13 PD patients undergoing deep brain stimulation implantation. We compared cortical (but not subcortical) dynamics with those recorded in 10 essential tremor (ET) patients, who do not have impairments in movement initiation. RESULTS: SI movements in PD are associated with greater low-beta (13-20 Hz) power suppression during pre-movement period in GPi and motor cortex compared to EC movements in PD and compared to SI movements in ET (motor cortex only). SI movements in PD are uniquely associated with significant low-beta pallidocortical coherence suppression during movement execution that correlates with bradykinesia severity. In ET, motor cortex neural dynamics during EC movements do not significantly differ from that observed in PD and do not significantly differ between SI and EC movements. CONCLUSION: These findings implicate low beta BGTC oscillations in impaired SI movements in PD. These results provide a physiological basis for the strategy of using EC movements in PD, circumventing diseased neural circuits associated with SI movements and instead engaging circuits that function similarly to those without PD.

13.
J Neurosci ; 40(30): 5833-5846, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32576623

RESUMO

Several lines of inquiry have separately identified beta oscillations, synchrony, waveform shape, and phase-amplitude coupling as important but sometimes inconsistent factors in the pathophysiology of Parkinson's disease. What has so far been lacking is a means by which these neurophysiological parameters are interrelated and how they relate to clinical symptomatology. To clarify the relationship among oscillatory power, bursting, synchrony, and phase-amplitude coupling, we recorded local field potentials/electrocorticography from hand motor and premotor cortical area in human subjects with c (N = 10) and Parkinson's disease (N = 22) during deep brain stimulator implantation surgery (14 females, 18 males). We show that motor cortical high beta oscillations in Parkinson's disease demonstrate increased burst durations relative to essential tremor patients. Notably, increased corticocortical synchrony between primary motor and premotor cortices precedes motor high beta bursts, suggesting a possible causal relationship between corticocortical synchrony and localized increases in beta power. We further show that high beta bursts are associated with significant changes in waveform shape and that beta-encoded phase-amplitude coupling is more evident during periods of high beta bursting. These findings reveal a deeper structure to the pathologic changes identified in the neurophysiology of Parkinson's disease, suggesting mechanisms by which the treatment may be enhanced using targeted network synchrony disruption approaches.SIGNIFICANCE STATEMENT Understanding Parkinson's disease pathophysiology is crucial for optimizing symptom management. Present inconsistencies in the literature may be explained by temporal transients in neural signals driven by transient fluctuations in network synchrony. Synchrony may also act as a unifying phenomenon for the pathophysiological observations reported in Parkinson's disease. Here, simultaneous recordings from motor cortices show that increases in network beta synchrony anticipate episodes of beta bursting. We furthermore identify beta bursting as being associated with changes in waveform shape and increases in phase-amplitude coupling. Our results identify network synchrony as a driver of various pathophysiological observations reported in the literature and account for inconsistencies in the literature by virtue of the temporally variable nature of the phenomenon.


Assuntos
Ritmo beta/fisiologia , Córtex Motor/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Adulto , Idoso , Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico
14.
J Neural Eng ; 16(6): 066034, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31505469

RESUMO

OBJECTIVE: Deep brain stimulation (DBS) has been demonstrated by numerous clinical trials to be an advanced therapy for selected patients with Parkinson's disease (PD), while its maximal therapeutic effect is capped by the inadequate understanding of the precise neuronal mechanisms underlying PD. Recordings from multichannel electrodes placed in subcortical and cortical regions of the basal ganglia-thalamocortical (BGTC) motor network during DBS surgical procedures can provide rich physiologic information from accessible network nodes. However, most investigations focus on presumed spatio-spectral points of interest, neither fully utilizing the richness of spatial, spectral and temporal aspects of the multivariate signals nor making discoveries in the context of all possible candidates. In addition, aggregated network-level information has been missed out. APPROACH: We use complex network analysis to characterize functional network characteristics of the pallidocortical subcircuit of the BGTC motor network in PD at rest and with movement. The network matrix was constructed using distinct frequency bands at each anatomic recording site as virtual nodes and spectral connectivity (through phase-amplitude coupling and coherence) as network edges. MAIN RESULTS: We confirm the critical roles of beta bands and provide additional evidence on their differential functional roles in the pallidocortical motor network. Moreover, significant changes (p  < 0.05) in network functional segregation and integration between rest and movement conditions are revealed for the first time. More importantly, movement-dependent modulation of these network metrics are significantly correlated with hemibody unified PD rating scales (UPDRS), providing network-level perspectives of the pallidocortical motor network pertaining to PD symptoms (p  < 0.05). SIGNIFICANCE: Findings in the present study provide network-level understanding of neuronal mechanisms in the pallidocortical motor network underlying PD. It is also highly plausible that the demonstrated approach can be applied in other important subcircuits towards a comprehensive understanding of the BGTC motor network.


Assuntos
Estimulação Encefálica Profunda/métodos , Globo Pálido/fisiopatologia , Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados , Humanos , Doença de Parkinson/diagnóstico
15.
Brain ; 142(8): 2288-2302, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31236577

RESUMO

Although the molecular effects of many anaesthetics have been well characterized, a network-level explanation for how these changes lead to loss of consciousness remains unclear. Studies using electroencephalography have characterized changes in neural oscillations in the cortex at specific frequency bands during propofol-induced anaesthesia and modelling work suggests these changes result from changes in thalamocortical functional connectivity. However, it is unclear if the neurophysiological changes seen at the cortex are due to enhanced or disrupted thalamocortical communication. Direct recordings from these sites during anaesthesia that could be used to confirm such models are rare. We recorded local field potentials from the ventral intermediate nucleus of the thalamus and electrocorticography signals from the ipsilateral sensorimotor cortex in 10 patients undergoing deep brain stimulation surgery. Signals were acquired during induction of propofol anaesthesia while subjects were resting. After confirming direct structural connectivity between the thalamus and the cortical recording site, we investigated propofol-associated changes in thalamic and cortical local power as well as thalamocortical functional connectivity, as measured with coherence, debiased weighted phase lag index, and phase amplitude coupling. Propofol anaesthesia resulted in local power increases at α frequencies (8-12 Hz) across both thalamic and cortical areas. At sensorimotor cortices, there was a broadband power increase (12-100 Hz), while the power of this same broad frequency band was suppressed within the thalamus. Despite the increase in local α power both within the thalamus and cortex, thalamocortical coherence and debiased weighted phase lag index in the α/low ß frequencies (8-16 Hz, which was present in the awake state) significantly decreased with propofol administration (P < 0.05, two group test of coherence). Likewise, propofol administration resulted in decreased phase amplitude coupling between the phase of α/low ß in the thalamus and the amplitude of broadband gamma (50-200 Hz) in the cortex (P = 0.031, Wilcoxon signed-rank test). We also report phase amplitude coupling between the phase of slow wave oscillations (0.1-1 Hz) and amplitude of broadband frequencies (8-200 Hz) within the cortex and across thalamocortical connections, during anaesthesia, both following a peak-max pattern. While confirming α-power increases with propofol administration both in thalamus and cortex, we observed decreased thalamocortical connectivity, contradicting models that suggest increasing cortical low frequency power is necessarily related to increased thalamocortical coherence but in support of the theory that propofol-induced loss of consciousness is associated with disrupted thalamocortical communication.


Assuntos
Anestésicos Intravenosos/farmacologia , Encéfalo/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Propofol/farmacologia , Inconsciência/induzido quimicamente , Idoso , Eletrocorticografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Stereotact Funct Neurosurg ; 96(4): 249-258, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30196280

RESUMO

BACKGROUND/AIMS: There are reports that microelectrode recording (MER) can be performed under certain anesthetized conditions for functional confirmation of the optimal deep brain stimulation (DBS) target. However, it is generally accepted that anesthesia affects MER. Due to a potential role of local field potentials (LFPs) in DBS functional mapping, we characterized the effect of propofol on globus pallidus interna (GPi) and externa (GPe) LFPs in Parkinson disease (PD) patients. METHODS: We collected LFPs in 12 awake and anesthetized PD patients undergoing DBS implantation. Spectral power of ß (13-35 Hz) and high-frequency oscillations (HFOs: 200-300 Hz) was compared across the pallidum. RESULTS: Propofol suppressed GPi power by > 20 Hz while increasing power at lower frequencies. A similar power shift was observed in GPe; however, power in the high ß range (20-35 Hz) increased with propofol. Before anesthesia both ß and HFO activity were significantly greater at the GPi (χ2 = 20.63 and χ2 = 48.81, p < 0.0001). However, during anesthesia, we found no significant difference across the pallidum (χ2 = 0.47, p = 0.79, and χ2 = 4.11, p = 0.12). CONCLUSION: GPi and GPe are distinguishable using LFP spectral profiles in the awake condition. Propofol obliterates this spectral differentiation. Therefore, LFP spectra cannot be relied upon in the propofol-anesthetized state for functional mapping during DBS implantation.


Assuntos
Anestésicos Intravenosos/administração & dosagem , Mapeamento Encefálico/métodos , Estimulação Encefálica Profunda/métodos , Globo Pálido/diagnóstico por imagem , Propofol/administração & dosagem , Idoso , Anestesia , Feminino , Globo Pálido/efeitos dos fármacos , Humanos , Masculino , Microeletrodos , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia
17.
Eur J Dent ; 12(3): 439-442, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30147413

RESUMO

OBJECTIVES: The present study aimed to assess oral health literacy level and its related factors among adult patients visiting Kerman Dental School. MATERIALS AND METHODS: This cross-sectional study was conducted in Kerman Dental School clinic, among the first-time adult visitors. Individuals were selected randomly from volunteers who signed study consent forms. Background information and oral health literacy levels were acquired through the oral health literacy-adult questionnaire. Statistical analysis including the Chi-square test and independent t-test served for statistical evaluation of the study data. RESULTS: Participants were 264 adults which consisted of 72.3% women and the mean age of 37 ± 8 years old. The mean oral health literacy score was 12.07 (out of 17), and 62.5% of the participants had an adequate oral health literacy level. There was a significant relationship between oral health literacy scores with gender, high level of education, and oral health behavior. CONCLUSION: The study participants had a good level of oral health literacy which can be correlated with their educational status and oral health information sources. An oral health educational program for less educated people is recommended.

18.
J Neural Eng ; 15(5): 056016, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29972146

RESUMO

ß hypersynchrony within the basal ganglia-thalamocortical (BGTC) network has been suggested as a hallmark of Parkinson disease (PD) pathophysiology. Subthalamic nucleus (STN)-DBS has been shown to alter cortical-subcortical synchronization. It is unclear whether this is a generalizable phenomenon of therapeutic stimulation across targets. OBJECTIVES: We aimed to evaluate whether DBS of the globus pallidus internus (GPi) results in cortical-subcortical desynchronization, despite the lack of monosynaptic connections between GPi and sensorimotor cortex. APPROACH: We recorded local field potentials from the GPi and electrocorticographic signals from the ipsilateral sensorimotor cortex, off medications in nine PD patients, undergoing DBS implantation. We analyzed both local oscillatory power and functional connectivity (coherence and debiased weighted phase lag index (dWPLI)) with and without stimulation while subjects were resting with eyes open. MAIN RESULTS: DBS significantly suppressed low ß power within the GPi (-26.98% ± 15.14%), p < 0.05) without modulation of sensorimotor cortical ß power (low or high). In contrast, stimulation suppressed pallidocortical high ß coherence (-38.89% ± 6.19%, p = 0.02) and dWPLI (-61.40% ± 8.75%, p = 0.02). Changes in cortical-subcortical functional connectivity were spatially specific to the motor cortex. SIGNIFICANCE: We highlight the role of DBS in desynchronizing network activity, particularly in the high ß band. The current study of GPi-DBS suggests these network-level effects are not necessarily dependent and potentially may be independent of the hyperdirect pathway. Importantly, these results draw a sharp distinction between the potential significance of low ß oscillations locally within the basal ganglia and high ß oscillations across the BGTC motor circuit.


Assuntos
Ritmo beta , Globo Pálido , Rede Nervosa/fisiopatologia , Doença de Parkinson/fisiopatologia , Idoso , Sincronização Cortical , Estimulação Encefálica Profunda , Estimulação Elétrica , Eletrocorticografia , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Córtex Sensório-Motor/fisiopatologia
19.
Front Hum Neurosci ; 12: 270, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30038563

RESUMO

There is converging evidence that bilateral basal ganglia motor networks jointly support normal movement behaviors including unilateral movements. The extent and manner in which these networks interact during lateralized movement remains unclear. In this study, simultaneously recorded bilateral Globus Pallidus interna (GPi) local field potentials (LFP) were examined from 19 subjects with idiopathic Parkinson disease (PD), while undergoing awake deep brain stimulation (DBS) implantation. Recordings were carried out during two behavioral states; rest and cued left hand movement (finger tapping). The state-dependent effects on α- ß oscillatory power and ß phase-encoded phase amplitude coupling (PAC), including symmetrical and assymetrical changes between hemispheres, were identified. Unilateral hand movement resulted in symmetrical oscillatory power suppression within bilateral GPi at α (8-12 Hz) and high ß (21-35 Hz) and increase in power of high frequency oscillations (HFO, 200-300 Hz) frequency bands. Asymmetrical attenuation was also observed at both low ß (13-20 Hz) and low γ (40-80 Hz) bands within the contralateral GPi (P = 0.009). In addition, unilateral movement effects on PAC were confined to the contralateral GPi with attenuation of both low ß-low γ and ß-HFO PAC (P < 0.05). Further analysis showed that the lateralized attenuation of low ß and low γ power did not correlate with low ß-low γ PAC changes. The overall coherence between bilateral GPi was not significantly altered with unilateral movement, however the preferred phase difference in the high ß range increased from 0.23 (±1.31) radians during rest to 1.99 (±0.78) radians during movement execution. Together, the present results suggest that unilateral motor control involves bilateral basal ganglia networks with movement features differentially encoded by distinct frequency bands. The lateralization of low ß and low γ attenuation with movement suggests that these frequency bands are specific to the motor act whereas symmetrical expression of α, high ß, and HFO oscillations best correspond to motor state. The restriction of movement-related PAC modulation to the contralateral GPi indicates that cross-frequency interactions appear to be associated with lateralized movements. Despite no significant movement-related changes in the interhemispheric coherence, the increase in phase difference suggests that the communication between bilateral GPi is altered with unilateral movement.

20.
Brain Stimul ; 11(3): 607-617, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29422442

RESUMO

OBJECTIVE: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) are equally efficacious in the management of Parkinson disease (PD). Studies of STN-DBS have revealed a therapeutic reduction in excessive cortical ß-γ phase-amplitude coupling (PAC). It is unclear whether this is specific to STN-DBS and potentially mediated by modulation of the hyperdirect pathway or if it is a generalizable mechanism seen with DBS of other targets. Moreover, it remains unclear how cortical signals are differentially modulated by movement versus therapy. To clarify, the effects of GPi-DBS and movement on cortical ß power and ß-γ PAC were examined. METHODS: Right sensorimotor electrocorticographic signals were recorded in 10 PD patients undergoing GPi-DBS implantation surgery. We evaluated cortical ß power and ß-γ PAC during blocks of rest and contralateral hand movement (finger tapping) with GPi-DBS off and on. RESULTS: Movement suppressed cortical low ß power (P = 0.008) and high ß-γ PAC (P = 0.028). Linear mixed effect modeling (LMEM) showed that power in low and high ß bands are differentially modulated by movement (P = 0.022). GPi-DBS also results in a significant suppression of high ß-γ PAC but without power modulation in either ß sub-band (P = 0.008). Cortical high ß-γ PAC is significantly correlated with severity of bradykinesia (Rho = 0.59, P = 0.045) and changes proportionally with therapeutic improvement (Rho = 0.61, P = 0.04). CONCLUSIONS: Similar to STN-DBS, GPi-DBS reduces motor cortical ß-γ PAC, like that also reported with dopaminergic mediations, suggesting it is a generalizable symptom biomarker in PD, independent of therapeutic target or proximity to the hyperdirect pathway.


Assuntos
Ritmo beta/fisiologia , Córtex Cerebral/fisiologia , Estimulação Encefálica Profunda , Ritmo Gama/fisiologia , Globo Pálido/fisiologia , Doença de Parkinson/terapia , Idoso , Eletrocorticografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Movimento/fisiologia
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