Sucrose consumption test.

<p>The rats were presented with a sucrose solution (1.5%) for one hour after 14 hours of food and water deprivation in order to evaluate their hedonic state during the CMS procedure (8 weeks). The studied animals showed a significant decrease of sucrose consumption in the anhedonic-like group, whereas the resilient animals showed no change compared with the control animals. The analysis was performed with two-way ANOVA for repeated measures. The data are presented as mean±SD. *p<.001. The figure was adapted from Delgado y Palacios <i>et al.</i> <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0095077#pone.0095077-DelgadoyPalacios1" target="_blank">[18]</a>.</p

Reproducibility between subjects of 40 components ICA (GIFT) of mouse rsfMRI.

<p>Pictures showing animal cumulative score maps for 16 selected ICA mice components (central slice) of the nine mice overlaid on the GE-EPI image. Colour-code: voxels with z-value higher than 1 for five animals (blue), six animals (blue-green), seven animals (orange), eight animals (red), nine animals (pink).</p

Results of the diffusion analysis of the amygdala.

<p>Groups mean (± SD) diffusion kurtosis (top) and diffusivity (bottom) parameters of the amygdala. One-way analysis of variance followed by post hoc least significant difference tests showed a significant increase of RD in both the anhedonic-like and resilient animals as compared with the unchallenged group. *p<.05 AD, Axial diffusion; AK, axial kurtosis; MD, mean diffusion; MK, mean kurtosis; RD, radial diffusion; RK, radial kurtosis.</p

Striatal functional connectivity maps resulting from 15 and 40 components ICA (GIFT) of rat rsfMRI.

<p>The figure shows 4 axial slices of mean components, located at the striatum. The spatial colour-coded z-maps of these components are overlaid on the GE-EPI image. A higher z-score (yellow) represents a higher correlation between the time course of that voxel and the mean time course of this component. For the 15 component analysis (A) the striatum was shown confined in only one component but was divided over two components for the 40 component analysis (B & C).</p

Results of the diffusion analysis of the caudate putamen.

<p>Mean (±SD) diffusion kurtosis (top) and diffusivity (bottom) parameters of the caudate putamen. One-way analysis of variance followed by post hoc least significant difference tests showed a significant increase of AD in both the anhedonic-like and resilient animals as compared with the unchallenged group. In addition, MK is significantly decreased in anhedonic-like animals as compared with resilient animals. *p<.05 AD, Axial diffusion; AK, axial kurtosis; MD, mean diffusion; MK, mean kurtosis; RD, radial diffusion; RK, radial kurtosis.</p

Regions of interest.

<p>The prefrontal cortex (blue), caudate putamen (red), amygdala (purple) and the somatosensory cortex (yellow) of the left (L) and the right (R) hemisphere were delineated on the B₀ images and the estimated diffusion parametric maps, referencing to a rat brain atlas <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0095077#pone.0095077-Paxinos1" target="_blank">[25]</a>.</p

Rendering of the whole brain, depicting the major areas (a, b, c) as well as all the 54 delineated structures (d, e, f).

<p>Three different angles are presented to maximize the number of brain regions per image: (a), (d) right view; (b), (e) partial frontal view; (c), (f) left view. In the first row of images it is possible to define six major areas: telencephalon (red), olfactory bulbs (pink) and part of the olfactory tracts (purple), optic tectum (brown) and part of the optic tracts (light blue), diencephalon (orange), cerebellum (yellow) and the brain stem (blue). For a complete list of the small nuclei identified and the color code for the remaining images see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044086#pone-0044086-g001" target="_blank">Fig. 1</a>.</p

Functional connectivity maps resulting from 40 components ICA (GIFT) of mouse rsfMRI.

<p>The figure shows 4 axial slices of the 16 mean components. The spatial colour-coded z-maps of these components are overlaid on the GE-EPI image. A higher z-score (yellow) represents a higher correlation between the time course of that voxel and the mean time course for this component. Mean components comprise (top-bottom) A) motorcortex, B) piriform cortex, CL) left somatosensory cortex, CR) right somatosensory cortex, DL) left auditory cortex, DR) right auditory cortex, E) right hippocampus (dorsal), F) ventral hippocampus, G) retrosplenial (dys)granular cortex, H) cingulate cortex, IL) left visual cortex, IR) right visual cortex, JL) left medial entorhinal cortex, JR) right medial entorhinal cortex, KL) left lateral entorhinal cortex and KR) right lateral entorhinal cortex.</p

Reproducibility between sessions and between subjects of 15 components ICA (GIFT) of rat rsfMRI.

<p>Left: Pictures showing session cumulative score maps for 9 selected mean ICA rat components (central slice) over the different time points overlaid on the GE-EPI image. Colour-code: voxels with z-value higher than 1 for one time point (blue), two time points (blue-green), three time points (orange), four time points (red). Right: Pictures showing animal cumulative score maps for 9 selected ICA rat components (central slice) of the five rats overlaid on the GE-EPI image. Colour-code: voxels with z-value higher than 1 for one animal (blue), two animals (blue-green), three animals (orange), four animals (red), five animals (pink).</p

Overview of the appearance of the main anatomical regions within each ICA analysis, comparing mouse and rat data for the 15 and 40 component analysis.

<p>Overview of the appearance of the main anatomical regions within each ICA analysis, comparing mouse and rat data for the 15 and 40 component analysis.</p