hi! for your question about understanding resting states, check Deco G et al. 2011 in Nature Reviews Neuroscience. I think is a good starting point. Cheers.

Resting state networks on the whole brain make more sense for human or Non Human Primate model. In this case resting state networks are those that share commonalities with cognitive networks during task conditions. The point is that task relevant networks are activated even in the absence of stimulus and carry important information about forthcoming stimuli.

For a mouse model I would simply say it is a spontaneous activity may be in your case over the whole cortex. Not sure you can call the same as resting state networks.

yes, but see Liu et al 2012 in PNAS, where they found a Default Mode Network in rats

You might be interested in this paper on spontaneous cortical activity in mice:

Spontaneous cortical activity alternates between motifs defined by regional axonal projections

http://www.ncbi.nlm.nih.gov/pubmed/?term=23974708

Did you check the following papers?

E. Jonckers, J. Van Audekerke, G. De Visscher, A. Van der Linden, M. Verhoye, Functional connectivity fMRI of the rodent brain: comparison of functional connectivity networks in rat and mouse, PLoS ONE 6, e18876 (2011).

L. Becerra, G. Pendse, P.-C. Chang, J. Bishop, D. Borsook, Robust Reproducible Resting State Networks in the Awake Rodent Brain, PLoS ONE 6, e25701 (2011).

Thanks to all for responding to my questions about the resting state brain activity!!! Its very helpful and giving sort of idea about the resting state of the brain, but I am still be looking for the details about how DEFAULT is the 'Default Mode Network'?

Once again thanks so much to all....

Here more detailed findings of DMN modulations are summarized

(but cave!: it’s a simple google translation from a german text!)

Most of the works dealing here with the connectivity of the RSN under different experimental conditions and psychiatric disorders (34 to 38). Zou et al. (34 ) could show that the thalamus in rest status has a negative correlation with the visual cortex, but is reduced with open eyes (EO) in comparison with eyes closed (EC). Both resting conditions were by Xu et al. (35 ) analyzed. They found different networks for the "exteroceptive" (EO ) compared to the "interoceptive" (EC ) processing and showed that the exteroceptive network (including the attentional system, eye motor system and arousal system) possesses higher regional characteristics (such as node degree , efficiency and Between centrality ). A similar finding describe also Di et al. ( 36) who found a higher global efficiency of task networks and conclude that the thalamus is considered to be a key nodes for switching. In a study by Shao et al. (37 ) a decrease of thalamocortical connectivity after 36 hours sleep deprivation was found, which concerned in particular the connections to the superior frontal gyrus, temporalis medius and parahippocampalis. Changes in the DMN during sleep were further by Chow et al. (38) investigated by means of combined rsfMRT and EEG. They found that the functional coupling in the DMN between MFPC and PCC during deep sleep (slow wave sleep) is reduced, but during the REM phases to a restitution the coupling occurs including the dorsal attention and frontal eye motor system.

34. Zou Q, Long X, Zuo X, et al. (2009) Functional connectivity between the thalamus and visual cortex under eyes closed and eyes open conditions: a resting-state fMRI study. Hum Brain Mapp 30:3066–3078.

35. Xu P, Huang R, Wang J, et al. Different topological organization of human brain functional networks with eyes open versus eyes closed. NeuroImage. doi: 10.1016/j.neuroimage.2013.12.060

36. Di X, Gohel S, Kim EH, Biswal BB (2013) Task vs. rest—different network configurations between the co-activation and the resting-state brain networks. Frontiers in Human Neuroscience. doi: 10.3389/ fnhum.2013.00493

37. Shao Y, Wang L, Ye E, et al. (2013) Decreased Thalamocortical Functional Connectivity after 36 Hours of Total Sleep Deprivation: Evidence from Resting State fMRI. PLoS ONE 8:e78830.

38. Chow HM, Horovitz SG, Carr WS, et al. (2013) Rhythmic alternating patterns of brain activity distinguish rapid eye movement sleep from other states of consciousness. PNAS 110:10300–10305.