| Title |
A VBM study demonstrating ‘apparent’ effects of a single dose of medication on T1-weighted MRIs
|
|---|---|
| Published in |
Brain Structure and Function, February 2012
|
| DOI | 10.1007/s00429-012-0385-6 |
| Pubmed ID | |
| Authors |
Teresa R. Franklin, Ze Wang, Joshua Shin, Kanchana Jagannathan, Jesse J. Suh, John A. Detre, Charles P. O’Brien, Anna Rose Childress |
| Abstract |
Voxel-based morphometry (VBM) studies have interpreted longitudinal medication- or behaviorally induced changes observed on T1-weighted magnetic resonance images (MRIs) as changes in neuronal structure. Although neurogenesis or atrophy certainly occurs, the use of T1-weighted scans to identify change in brain structure in vivo in humans has vulnerability: the T1 relaxation time for arterial blood and gray matter are not clearly distinguishable and therefore, apparent reported structural findings might be at least partially related to changes in blood flow or other physiological signals. To examine the hypothesis that apparent structural modifications may reflect changes introduced by additional mechanisms irrespective of potential neuronal growth/atrophy, we acquired a high-resolution T1-weighted structural scan and a 5-min perfusion fMRI scan (a measurement of blood flow), before and after administration of an acute pharmacological manipulation. In a within-subject design, 15 subjects were either un-medicated or were administered a 20 mg dose of baclofen (an FDA-approved anti-spastic) approximately 110 min before acquiring a T1-weighted scan and a pseudo continuous arterial spin labeled perfusion fMRI scan. Using diffeomorphic anatomical registration through exponentiated lie algebra within SPM7, we observed macroscopic, and therefore implausible, baclofen-induced decreases in VBM 'gray matter' signal in the dorsal rostral anterior cingulate (family wise error corrected at p<0.04, T = 6.54, extent: 1,460 voxels) that overlapped with changes in blood flow. Given that gray matter reductions are unlikely following a single dose of medication these findings suggest that changes in blood flow are masquerading as reductions in gray matter on the T1-weighted scan irrespective of the temporal interval between baseline measures and longitudinal manipulations. These results underscore the crucial and immediate need to develop in vivo neuroimaging biomarkers for humans that can uniquely capture changes in neuronal structure dissociable from those related to blood flow or other physiological signals. |
X Demographics
The data shown below were collected from the profiles of 4 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Italy | 1 | 25% |
| United Kingdom | 1 | 25% |
| Unknown | 2 | 50% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 3 | 75% |
| Scientists | 1 | 25% |
Mendeley readers
The data shown below were compiled from readership statistics for 85 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United Kingdom | 2 | 2% |
| Spain | 2 | 2% |
| Netherlands | 1 | 1% |
| United States | 1 | 1% |
| Unknown | 79 | 93% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 17 | 20% |
| Student > Ph. D. Student | 16 | 19% |
| Student > Master | 8 | 9% |
| Professor | 6 | 7% |
| Student > Postgraduate | 6 | 7% |
| Other | 19 | 22% |
| Unknown | 13 | 15% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 19 | 22% |
| Neuroscience | 16 | 19% |
| Psychology | 15 | 18% |
| Agricultural and Biological Sciences | 8 | 9% |
| Computer Science | 2 | 2% |
| Other | 5 | 6% |
| Unknown | 20 | 24% |
Attention Score in Context
This research output has an Altmetric Attention Score of 4. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 08 December 2021.
All research outputs
#7,629,858
of 26,017,215 outputs
Outputs from Brain Structure and Function
#583
of 2,081 outputs
Outputs of similar age
#63,440
of 259,951 outputs
Outputs of similar age from Brain Structure and Function
#5
of 14 outputs
Altmetric has tracked 26,017,215 research outputs across all sources so far. This one has received more attention than most of these and is in the 69th percentile.
So far Altmetric has tracked 2,081 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 6.8. This one has gotten more attention than average, scoring higher than 70% of its peers.
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