Lateralization of amygdala activation in fMRI may depend on phase-encoding polarity.
Summary of "Lateralization of amygdala activation in fMRI may depend on phase-encoding polarity."
Susceptibility artifacts along the phase-encoding (PE) direction impact the activation pattern in the amygdala and may lead to systematic asymmetries. We implemented a triple-echo echo-planar imaging (EPI) sequence, acquiring opposite PE polarities along left-right PE direction in a single shot, to investigate its effects on amygdala lateralization. MATERIALS AND
Twelve subjects viewed emotional faces to evoke amygdala activation. RESULTS AND
A region of interest analysis revealed that the lateralization of amygdala responses depended on the PE polarity thus representing a pure method artifact. Alternating PE with multi-echo EPI reduced the artifact. Lateralized fMRI activation in areas with magnetic field inhomogeneities need to be interpreted with caution.
Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Neuenhofer Weg 21, 52074, Aachen, Germany, firstname.lastname@example.org.
This article was published in the following journal.
Name: Magma (New York, N.Y.)
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22009130
- DOI: http://dx.doi.org/10.1007/s10334-011-0285-4
Medical and Biotech [MESH] Definitions
Almond-shaped group of basal nuclei anterior to the inferior horn of the lateral ventricle of the brain, within the temporal lobe. The amygdala is part of the limbic system.
The interval between two successive CELL DIVISIONS during which the CHROMOSOMES are not individually distinguishable. It is composed of the G phases (G1 PHASE; G0 PHASE; G2 PHASE) and S PHASE (when DNA replication occurs).
Metabolic Detoxication, Phase I
Functionalization of exogenous substances to prepare them for conjugation in PHASE II DETOXIFICATION. Phase I enzymes include CYTOCHROME P450 enzymes and some OXIDOREDUCTASES. Excess induction of phase I over phase II detoxification leads to higher levels of FREE RADICALS that can induce CANCER and other cell damage. Induction or antagonism of phase I detoxication is the basis of a number of DRUG INTERACTIONS.
The period of the CELL CYCLE following DNA synthesis (S PHASE) and preceding M PHASE (cell division phase). The CHROMOSOMES are tetraploid in this point.
The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.
We present a comprehensive and clinically applicable fMRI test-including both a verbal and a visuospatial task-for assessment of hemispheric specific memory in the medial temporal lobe (MTL). fMRI dat...
Surgery is often the only effective treatment for intractable epilepsy, but its benefits must be balanced by potential disruption of eloquent cortical functions. Wada test is the standard technique to...
Sex differences in various cognitive abilities have been demonstrated in terms of performance differentials and, more recently, in differences in activation patterns during fMRI. Hemispheric lateraliz...
Language is typically a function of the left hemisphere but the right hemisphere is also essential in some healthy individuals and patients. This inter-subject variability necessitates the localizatio...
The present study investigated when emotion modulates working memory from the perspective of neural activation. Using fMRI, we measured brain activity during the encoding and retrieval phases of a rea...
1. Young adults who are exposed to 7-10 days of play of violent video games will show reduced activation in certain regions of the dorsolateral prefrontal cortex and anterior cin...
The purpose of this study is to assess the effectiveness of polarity therapy (PT), a complementary and alternative medicine treatment, in American Indian caregivers living in the Pacific N...
The aim of the protocol is to study the resting brain activation profile of 3 groups of people, using a new fMRI procedure, called fMRI-SAM. fMRI-SAM will be applied to 25 Alzheimer's dise...
Anxiety in children of parents with major depressive disorder (MDD) poses a particularly high risk for later-life MDD. In adults, MDD involves dysfunction in prefrontal brain regions that...
The investigators hypothesis is that HVPC with negative polarity diminishes local post-traumatic edema in ankle sprains. Therefore, the objective of this study was to analyze the effect of...