Significance of Non-phase Locked Oscillatory Brain Activity in Response to Noxious Stimuli.
Can J Neurol Sci
; 42(6): 436-43, 2015 Nov.
Article
en En
| MEDLINE
| ID: mdl-26329603
BACKGROUND: Although current pain-evoked electroencephalographic (EEG) studies provide valuable information regarding human brain regions involved in pain, they have mostly considered neuronal responses which oscillate in phase following a painful event. In many instances, cortical neurons respond by generating bursts of activity that are slightly out of phase from trial-to-trial. These types of activity bursts are known as induced brain responses. The significance of induced brain responses to pain is still unknown. METHODS: In this study, 23 healthy subjects were given both non-painful and painful transcutaneous electrical stimulations in separate testing blocks (stimulation strength was kept constant within blocks). Subjective intensity was rated using a numerical rating scale, while cerebral activity tied to each stimulation was measured using EEG recordings. Induced brain responses were identified using a time frequency wavelet transform applied to average-removed single trials. RESULTS: Results showed a pain-specific burst of induced theta activity occurring between 180 and 500 ms post-shock onset. Source current density estimations located this activity within the dorsolateral prefrontal cortex (DLPFC, bilaterally), however, only right DLPFC activity predicted a decrease in subjective pain as testing progressed. CONCLUSION: This finding suggests that non-phase locked neuronal responses in the right DLPFC contribute to the endogenous attenuation of pain through time. PERSPECTIVE: This article presents neuroimaging findings demonstrating that, in response to pain, non-phase locked bursts of theta activity located in the right dorsolateral prefrontal cortex are associated with a progressive decrease in subjective pain intensity, which has potentially important implications regarding how humans endogenously control their experiences of pain.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Encéfalo
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Mapeo Encefálico
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Estimulación Eléctrica
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Electroencefalografía
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Neuroimagen
Tipo de estudio:
Diagnostic_studies
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Prognostic_studies
Límite:
Adult
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Female
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Humans
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Male
Idioma:
En
Revista:
Can J Neurol Sci
Año:
2015
Tipo del documento:
Article
Pais de publicación:
Reino Unido