Contralateral dissociation between neural activity and cerebral blood volume during recurrent acute focal neocortical seizures
File(s)Harris_et_al-2014-Epilepsia.pdf (1.03 MB)
Published version
Author(s)
Type
Journal Article
Abstract
OBJECTIVE: Whether epileptic events disrupt normal neurovascular coupling mechanisms locally or remotely is unclear. We sought to investigate neurovascular coupling in an acute model of focal neocortical epilepsy, both within the seizure onset zone and in contralateral homotopic cortex. METHODS: Neurovascular coupling in both ipsilateral and contralateral vibrissal cortices of the urethane-anesthetized rat were examined during recurrent 4-aminopyridine (4-AP, 15 mm, 1 μl) induced focal seizures. Local field potential (LFP) and multiunit spiking activity (MUA) were recorded via two bilaterally implanted 16-channel microelectrodes. Concurrent two-dimensional optical imaging spectroscopy was used to produce spatiotemporal maps of cerebral blood volume (CBV). RESULTS: Recurrent acute seizures in right vibrissal cortex (RVC) produced robust ipsilateral increases in LFP and MUA activity, most prominently in layer 5, that were nonlinearly correlated to local increases in CBV. In contrast, contralateral left vibrissal cortex (LVC) exhibited relatively smaller nonlaminar specific increases in neural activity coupled with a decrease in CBV, suggestive of dissociation between neural and hemodynamic responses. SIGNIFICANCE: These findings provide insights into the impact of epileptic events on the neurovascular unit, and have important implications both for the interpretation of perfusion-based imaging signals in the disorder and understanding the widespread effects of epilepsy. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.
Date Issued
2014-07-22
Online Publication Date
2014-07-22
2016-10-26T10:29:44Z
Date Acceptance
2014-06-10
ISSN
1528-1167
Publisher
Wiley
Start Page
1423
End Page
1430
Journal / Book Title
Epilepsia
Volume
55
Issue
9
Copyright Statement
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Source Database
pubmed
Subjects
4-Aminopyridine
Electrophysiology
Neurovascular coupling
Optical imaging spectroscopy
Animals
Brain Mapping
Cerebrovascular Circulation
Disease Models, Animal
Electroencephalography
Epilepsy
Female
Functional Laterality
Hemodynamics
Potassium Channel Blockers
Rats
Recurrence
Somatosensory Cortex
Statistics, Nonparametric
Neurology & Neurosurgery
1103 Clinical Sciences
1109 Neurosciences
Publication Status
Published