Diferencias en la resonancia magnética funcional en pacientes con trastorno bipolar usando un paradigma de memoria de trabajo1 1Este artículo recibió financiación de la Universidad de Antioquia y el Instituto de Alta Tecnología Médica de Antioquia (IATM). Este trabajo sirvió como tesis para optar al título de especialista en Psiquiatría del Dr. Andrés Correa, Universidad de Antioquia, 2010

A systematic literature review of resting state network--functional MRI in bipolar disorder

BACKGROUND

Several studies using functional magnetic resonance imaging (fMRI) in bipolar disorder (BD) have been performed in the last decade. Some of them have applied novel neuroimaging techniques such as resting-state functional connectivity magnetic resonance imaging (rs-fcMRI).

METHODS

We reviewed the top-quality rs-fcMRI studies in BD available in the PubMed and Embase databases up to November, 2012 to identify brain activation networks and research techniques that may benefit future research.

RESULTS

We present and discuss the methods and findings of eight articles. Most of these studies used the regions-of-interest (ROI) and independent component analysis (ICA) methods, and some used approaches such as amplitude of low-frequency fluctuation (ALFF), restricted global brain connectivity (rGBC) and regional homogeneity (ReHO). The largest differences in their results were found in the connectivity of the medial prefrontal cortex (mPFC) and the anterior cingulated cortex with limbic-striatal structures, and in spatial extent in ReHo when studying the default mode network (DMN).

LIMITATIONS

The heterogeneity of the analytical methods used to explore the resting-state network (RSN) and the characteristics of the sample of each study limit the conclusions.

CONCLUSIONS

Despite the variation among the results of the reviewed papers, they all support the cortico-limbic hypothesis and suggest that connectivity can be more complex and that intra-regional disturbances should also be studied. Recommendations for future studies include consideration of intra-regional disturbances, better control of confounding factors, use of larger scale methods, and a consensus regarding how to approach the study of resting-state networks and interpret the results obtained.

[Report of Internal Consistency of the Scales in Research Published in the Colombian Journal of Psychiatry]

OBJECT

Establishment of the frequency of reporting internal consistency of the scales in research published in the Colombian Journal of Psychiatry (CJP) between 2006 and 2010.

METHOD

A descriptive study was carried out which computes the report of internal consistency (Cronbach alpha) of scales in research published as original papers in the CJP. Validation studies were excluded.

RESULTS

A total of 114 articles were published and 30 of them were included in the analysis. Researchers applied 67 scales for measuring some variables and Cronbach alpha of 20 (29.8%) scales was reported in the participating population.

CONCLUSIONS

In the CJP, few published studies that apply measuring scales for variables report internal consistency in the analyzed sample. It is necessary for authors to report the internal consistency of used scales in the study population to guarantee the validity of conclusions.