Papers by Jeffrey Stanley
Psychiatry Research: Neuroimaging, 2014
Obsessive-compulsive disorder (OCD) has a typical onset during childhood or adolescence. Although... more Obsessive-compulsive disorder (OCD) has a typical onset during childhood or adolescence. Although recent in-vivo proton magnetic resonance spectroscopy ((1)H-MRS) studies report gray matter metabolite abnormalities in children and adolescents with OCD, there are no existing (1)H-MRS studies that measure white matter (WM) metabolite levels in this population. In the present study, we measured metabolite levels in the left and right prefrontal WM (LPFWM and RPFWM, respectively) of psychotropic-naïve children and adolescents with OCD (LPFWM: N=15, mean age 13.3±2.4 years; right RPFWM: N=14, mean age 13.0±2.3 years) and healthy controls (LPFWM: N=17, mean age 11.8±2.7 years; RPFWM: N=18, mean age 12.2±2.8 years). Spectra were acquired using a 3T single voxel PRESS sequence (1.5×2.0×2.0cm(3)). When age and sex effects were controlled, OCD patients had higher levels of RPFWM choline and N-acetyl-aspartate (NAA). In addition, RPFWM levels of NAA, creatine and myo-inositol were positively and significantly correlated with severity of OCD symptoms. In summary, this is the first published study of WM metabolite levels in children and adolescents with OCD. Our preliminary findings lend further support to the previous findings of WM abnormalities in OCD.
Neuropsychopharmacology, 2002
The effects of acute lorazepam administration on 1 H magnetic resonance spectroscopy (MRS) in viv... more The effects of acute lorazepam administration on 1 H magnetic resonance spectroscopy (MRS) in vivo brain spectra were examined in the left dorsolateral prefrontal cortex (L-DLPFC) of healthy human subjects. We wanted to examine whether lorazepam administration would result in significant changes in the levels of 1 H-MRS metabolites in this brain region. Ten healthy controls underwent a short echo-time 1 H-MRS session immediately before, and a second one 1 h after lorazepam administration (2mg/orally). The measured 1 H-metabolites included N-acetyl-aspartate, phosphocreatine ϩ creatine, trimethylamines, myo-inositol, glutamate, and glutamine, which were expressed as absolute values and ratios. No significant differences were found after lorazepam administration for any of the measured metabolite levels or ratios (paired t-tests, p Ͼ .05). This study demonstrated that lorazepam can potentially be utilized to acutely sedate psychiatric subjects during in vivo 1 H-MRS sessions, as it does not appear to produce significant changes in the 1 H-MRS spectra in this specific brain region.
Annals of Neurology, 1997
We performed proton magnetic resonance spectroscopic imaging of the temporal lobes between, durin... more We performed proton magnetic resonance spectroscopic imaging of the temporal lobes between, during, and soon after nonconvulsive seizures in 20 patients with documented temporal lobe epilepsy, 5 patients with primary generalized epilepsy, and 2 patients with secondary generalized epilepsy. Our objective was to determine whether there were metabolic changes observable by magnetic resonance spectroscopic imaging during seizures and whether these changes were specific for focal or generalized nonconvulsive seizures. We found a significant increase in lactate to creatine plus phosphocreatine (lactate/creatine) values, reflecting an imbalance in energy supply and demand or an adaptation in response to ictal neuronal discharges, during and soon after complex partial seizures, but not during or soon after absence seizures associated with generalized epilepsy. In patients with temporal lobe epilepsy, the N-acetylaspartate resonance relative to creatine plus phosphocreatine was low in one or both temporal lobes, indicating neuronal loss or damage. This was not observed in patients with primary generalized epilepsy. The regions with abnormal lactate/creatine and N-acetylaspartate/creatine values corresponded to the epileptogenic focus as defined by clinical-electroencephalographic investigation. There was no change in the N-acetylaspartate/creatine values in the temporal lobes between the interictal, ictal, or postictal states. We conclude that (1) partial seizures are associated with abnormally high lactate levels, but absence seizures are not, and (2) no short-term changes of N-acetylaspartate occur during or soon after complex partial seizures or absence seizures. These findings may be related to the lack of postictal confusion in patients with absence seizures, as well as with the more benign course of primary generalized epilepsy with nonconvulsive attacks.
Brain Communications
Pelizaeus–Merzbacher disease is an X-linked recessive leucodystrophy of the central nervous syste... more Pelizaeus–Merzbacher disease is an X-linked recessive leucodystrophy of the central nervous system caused by mutations affecting the major myelin protein, proteolipid protein 1. The extent of the altered in vivo neurochemistry of protein, proteolipid protein 1 duplications, the most common form of Pelizaeus–Merzbacher disease, is, however, poorly understood. Phosphorus magnetic resonance spectroscopy is the only in vivo technique that can assess the biochemistry associated with high-energy phosphate and membrane phospholipid metabolism across different cortical, subcortical and white matter areas. In this cross-sectional study, whole-brain, multi-voxel phosphorus magnetic resonance spectroscopy was acquired at 3 T on 14 patients with Pelizaeus–Merzbacher disease with protein, proteolipid protein 1 duplications and 23 healthy controls (all males). Anabolic and catabolic levels of membrane phospholipids (phosphocholine and phosphoethanolamine, and glycerophosphoethanolamine and glycer...
Molecular Psychiatry, 2003
NeuroImage, Jun 29, 2017
fMRI has provided vibrant characterization of regional and network responses associated with asso... more fMRI has provided vibrant characterization of regional and network responses associated with associative learning and memory; however, their relationship to functional neurochemistry is unclear. Here, we introduce a novel application of in vivo proton functional magnetic resonance spectroscopy ((1)H fMRS) to investigate the dynamics of hippocampal glutamate during paired-associated learning and memory in healthy young adults. We show that the temporal dynamics of glutamate differed significantly during processes of memory consolidation and retrieval. Moreover, learning proficiency was predictive of the temporal dynamics of glutamate such that fast learners were characterized by a significant increase in glutamate levels early in learning, whereas this increase was only observed later in slow learners. The observed functional dynamics of glutamate provides a novel in vivo marker of brain function. Previously demonstrated N-methyl-D-aspartate (NMDA) receptor mediated synaptic plastici...
Innovation in Aging
Hippocampal glutamatergic activity plays a pivotal role in memory consolidation, including the ab... more Hippocampal glutamatergic activity plays a pivotal role in memory consolidation, including the ability to form novel associations that declines with age. To test whether glutamatergic dysfunction may underpin age-related memory declines, we examined in vivo age differences in hippocampal glutamate modulation during encoding of associations, and its relationship with hippocampal subfield volumes. Proton functional magnetic resonance spectroscopy was performed on 32 young (25.1±2.8 years; 18 females) and 16 older (65.9±2.7 years; 7 females) adults to measure changes in hippocampal (randomly assigned right or left) glutamate during an object-location paired association learning task (with 12 cycles of encoding-retrieval epochs). Volumes of the dentate gyrus&CA3, CA1, subiculum, and entorhinal cortex were manually measured from T2-weighted MRI images. Memory performance differed between the age-groups [F(1, 46)=8.56, p
Innovation in Aging
The corpus callosum (CC) connects homologous cortical structures across hemispheres and is the la... more The corpus callosum (CC) connects homologous cortical structures across hemispheres and is the largest white matter tract in the human brain. Post-mortem studies suggest that CC myelination begins in infancy, reaches a plateau in the middle age, and declines in the later years. The latter is accompanied by myelin disruption and reduction in fiber density and diameter, i.e. changes in intra-/extracellular water space. We used multi-echo T2 imaging to estimate, via multi-exponential T2 relaxation of water, the myelin water fraction (MWF), a direct proxy for myelin content, and geometric mean T2 (geomT2IEW) that reflects water in the intra-/extracellular space, to investigate age differences in five CC regions covering its anterior to posterior span in 395 healthy individuals (7-85 years; 161M+235F). The general linear model analysis of MWF showed main effects of age and age-squared conditioned on interactions by CC region. Univariate polynomial regressions on three age groups (7-29, 3...
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Papers by Jeffrey Stanley