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Striatal volume increases in active methamphetamine-dependent individuals and correlation with cognitive performance.

Jan RK, Lin JC, Miles SW, Kydd RR, Russell BR - Brain Sci (2012)

Bottom Line: MA-dependent participants exhibited cortical GM deficits in the left superior frontal and precentral gyri in comparison to control participants, although these findings did not survive correction for multiple comparisons.In conclusion, consistent with findings from previous studies of abstinent users, active chronic MA-dependent participants showed significant striatal enlargement which was associated with improved performance on the Go/No-go, a cognitive task of response inhibition and impulsivity.Follow-up studies are recommended to ascertain whether this effect continues to be present following abstinence.

View Article: PubMed Central - PubMed

Affiliation: School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. r.jan@auckland.ac.nz.

ABSTRACT
The effect of methamphetamine (MA) dependence on the structure of the human brain has not been extensively studied, especially in active users. Previous studies reported cortical deficits and striatal gains in grey matter (GM) volume of abstinent MA abusers compared with control participants. This study aimed to investigate structural GM changes in the brains of 17 active MA-dependent participants compared with 20 control participants aged 18-46 years using voxel-based morphometry and region of interest volumetric analysis of structural magnetic resonance imaging data, and whether these changes might be associated with cognitive performance. Significant volume increases were observed in the right and left putamen and left nucleus accumbens of MA-dependent compared to control participants. The volumetric gain in the right putamen remained significant after Bonferroni correction, and was inversely correlated with the number of errors (standardised z-scores) on the Go/No-go task. MA-dependent participants exhibited cortical GM deficits in the left superior frontal and precentral gyri in comparison to control participants, although these findings did not survive correction for multiple comparisons. In conclusion, consistent with findings from previous studies of abstinent users, active chronic MA-dependent participants showed significant striatal enlargement which was associated with improved performance on the Go/No-go, a cognitive task of response inhibition and impulsivity. Striatal enlargement may reflect the involvement of neurotrophic effects, inflammation or microgliosis. However, since it was associated with improved cognitive function, it is likely to reflect a compensatory response to MA-induced neurotoxicity in the striatum, in order to maintain cognitive function. Follow-up studies are recommended to ascertain whether this effect continues to be present following abstinence. Several factors may have contributed to the lack of more substantial cortical and subcortical GM changes amongst MA-dependent participants, including variability in MA exposure variables and difference in abstinence status from previous studies.

No MeSH data available.


Related in: MedlinePlus

Mean ± standard error subcortical volumes in control participants (n = 20) and MA-dependent participants (n = 17), * p < 0.05 before Bonferroni correction, ** significant after Bonferroni correction.
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brainsci-02-00553-f001: Mean ± standard error subcortical volumes in control participants (n = 20) and MA-dependent participants (n = 17), * p < 0.05 before Bonferroni correction, ** significant after Bonferroni correction.

Mentions: After controlling for the effect of volumetric scaling factor (VSF), MA-dependent participants had higher volumes than controls in the right putamen (+7.52%; F(1,36) = 8.91, p = 0.005), left putamen (+7.34%; F(1,36) = 5.83, p = 0.021) and left nucleus accumbens (+9.85%; F(1,36) = 6.63, p = 0.015) (Figure 1). However, the only group difference that remained significant after Bonferroni correction was the volume increase in the right putamen of MA-dependent participants. Relative to the control group, MA-dependent participants had greater volumes in the bilateral globus pallidus, and lower volumes in the bilateral caudate, however these results were not statistically significant (Figure 1).


Striatal volume increases in active methamphetamine-dependent individuals and correlation with cognitive performance.

Jan RK, Lin JC, Miles SW, Kydd RR, Russell BR - Brain Sci (2012)

Mean ± standard error subcortical volumes in control participants (n = 20) and MA-dependent participants (n = 17), * p < 0.05 before Bonferroni correction, ** significant after Bonferroni correction.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4061811&req=5

brainsci-02-00553-f001: Mean ± standard error subcortical volumes in control participants (n = 20) and MA-dependent participants (n = 17), * p < 0.05 before Bonferroni correction, ** significant after Bonferroni correction.
Mentions: After controlling for the effect of volumetric scaling factor (VSF), MA-dependent participants had higher volumes than controls in the right putamen (+7.52%; F(1,36) = 8.91, p = 0.005), left putamen (+7.34%; F(1,36) = 5.83, p = 0.021) and left nucleus accumbens (+9.85%; F(1,36) = 6.63, p = 0.015) (Figure 1). However, the only group difference that remained significant after Bonferroni correction was the volume increase in the right putamen of MA-dependent participants. Relative to the control group, MA-dependent participants had greater volumes in the bilateral globus pallidus, and lower volumes in the bilateral caudate, however these results were not statistically significant (Figure 1).

Bottom Line: MA-dependent participants exhibited cortical GM deficits in the left superior frontal and precentral gyri in comparison to control participants, although these findings did not survive correction for multiple comparisons.In conclusion, consistent with findings from previous studies of abstinent users, active chronic MA-dependent participants showed significant striatal enlargement which was associated with improved performance on the Go/No-go, a cognitive task of response inhibition and impulsivity.Follow-up studies are recommended to ascertain whether this effect continues to be present following abstinence.

View Article: PubMed Central - PubMed

Affiliation: School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. r.jan@auckland.ac.nz.

ABSTRACT
The effect of methamphetamine (MA) dependence on the structure of the human brain has not been extensively studied, especially in active users. Previous studies reported cortical deficits and striatal gains in grey matter (GM) volume of abstinent MA abusers compared with control participants. This study aimed to investigate structural GM changes in the brains of 17 active MA-dependent participants compared with 20 control participants aged 18-46 years using voxel-based morphometry and region of interest volumetric analysis of structural magnetic resonance imaging data, and whether these changes might be associated with cognitive performance. Significant volume increases were observed in the right and left putamen and left nucleus accumbens of MA-dependent compared to control participants. The volumetric gain in the right putamen remained significant after Bonferroni correction, and was inversely correlated with the number of errors (standardised z-scores) on the Go/No-go task. MA-dependent participants exhibited cortical GM deficits in the left superior frontal and precentral gyri in comparison to control participants, although these findings did not survive correction for multiple comparisons. In conclusion, consistent with findings from previous studies of abstinent users, active chronic MA-dependent participants showed significant striatal enlargement which was associated with improved performance on the Go/No-go, a cognitive task of response inhibition and impulsivity. Striatal enlargement may reflect the involvement of neurotrophic effects, inflammation or microgliosis. However, since it was associated with improved cognitive function, it is likely to reflect a compensatory response to MA-induced neurotoxicity in the striatum, in order to maintain cognitive function. Follow-up studies are recommended to ascertain whether this effect continues to be present following abstinence. Several factors may have contributed to the lack of more substantial cortical and subcortical GM changes amongst MA-dependent participants, including variability in MA exposure variables and difference in abstinence status from previous studies.

No MeSH data available.


Related in: MedlinePlus