PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 8722662

Functional neuroimaging: radiology.

J V Hunter
View original source ↗Export metadata ↓

Abstract

Rapid advances, in respect of the visual and auditory systems, have occurred in neuroimaging over the past year in the area of so-called 'functional imaging', and in particular of functional magnetic resonance imaging. This has been accelerated by the introduction of echo-planar imaging, which allows for the very fast acquisition (< 100 ms/image) of multislice images. Radiology is no longer just a question of interpreting anatomy, for, with the ability to combine structure with function, we are now able to extract physiological information. This opens up exciting possibilities for advances in the field of neuroscience, and functional imaging will therefore form the main thrust of this review.

Explore related subjects

Auditory CortexBrainHumansImage Processing, Computer-AssistedNeural PathwaysRadionuclide ImagingJournal ArticleReview

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J V Hunter. 1996. Functional neuroimaging: radiology.. https://doi.org/10.1097/00019052-199602000-00008

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Temporal lobe interictal epileptic discharges affect cerebral activity in "default mode" brain regions.

A cerebral network comprising precuneus, medial frontal, and temporoparietal cortices is less active both during goal-directed behavior and states of reduced consciousness than during conscious rest. We tested the hypothesis that the interictal epileptic discharges affect activity in these brain regions in patients with temporal lobe epilepsy who have complex partial seizures. At the group level, using electroencephalography-correlated functional magnetic resonance imaging in 19 consecutive patients with focal epilepsy, we found common decreases of resting state activity in 9 patients with temporal lobe epilepsy (TLE) but not in 10 patients with extra-TLE. We infer that the functional consequences of TLE interictal epileptic discharges are different from those in extra-TLE and affect ongoing brain function. Activity increases were detected in the ipsilateral hippocampus in patients with TLE, and in subthalamic, bilateral superior temporal and medial frontal brain regions in patients with extra-TLE, possibly indicating effects of different interictal epileptic discharge propagation.

Auditory Cortex↗
PubMed2006

Beamformer reconstruction of correlated sources using a modified source model.

This paper introduces a lead field formulation for use in beamformer analysis of MEG data. This 'dual source beamformer' is a technique to image two temporally correlated sources using beamformer methodology. We show that while the standard, single source beamformer suppresses the reconstructed power of two spatially separate but temporally correlated sources, the dual source beamformer allows for their accurate reconstruction. The technique is proven to be accurate using simulations. We also show that it can be used to image accurately the auditory steady state response, which is correlated between the left and right auditory cortices. We suggest that this technique represents a useful way of locating correlated sources, particularly if a seed location can be defined a priori for one of the two sources. Such a priori information could be based on previous studies using similar paradigms, or from other functional neuroimaging techniques.

Auditory Cortex↗
PubMed2006

Electrophysiological response patterns of primary sensory cortices in migraine.

Migraine is an ictal disorder characterised by a particular vulnerability of patients to sensory overload, both during and outside of the attack. Central nervous system dysfunctions are supposed to play a pivotal role in migraine. Electroneurophysiological methods, which aim to investigate sensory processing, seem thus particularly appropriate to study the pathophysiology of migraine. We have thus reviewed evoked potential studies performed in migraine patients. Although results are in part contradictory, these studies nonetheless demonstrate an interictal dysfunction of sensory cortices, and possibly of subcortical structures, in migraine with and without aura. The predominant abnormality is a deficient habituation of evoked responses to repeated stimuli, probably due to cortical, and possibly widespread neural, "dysexcitability".

Auditory Cortex↗