A 3-dimensional digital atlas of the ascending sensory and the descending motor systems in the pigeon brain

Abstract

Pigeons are classic animal models for learning, memory, and cognition. The majority of the current understanding about avian neurobiology outside of the domain of the song system has been established using pigeons. Since MRI represents an increasingly relevant tool for comparative neuroscience, a 3-dimensional MRI-based atlas of the pigeon brain becomes essential. Using multiple imaging protocols, we delineated diverse ascending sensory and descending motor systems as well as the hippocampal formation. This pigeon brain atlas can easily be used to determine the stereotactic location of identified neural structures at any angle of the head. In addition, the atlas is useful to find the optimal angle of sectioning for slice experiments, stereotactic injections and electrophysiological recordings. This pigeon brain atlas is freely available for the scientific community.

Functional MRI and functional connectivity of the visual system of awake pigeons

“…The realigned fMRI images for each subject were then co-registered to each individual anatomical 3D dataset. In parallel, the 3D dataset was spatially normalized, using SPM8, to the pigeon brain MRI atlas that we developed in our lab [38]. The transformation matrix of this spatial normalization was then applied to the realigned and co-registered functional data, resulting in functional data precisely co-registered to the atlas dataset.…”

“…The statistical group analysis was restricted to the entopallium and the visual Wulst as a priori defined regions of interest (ROI) using the delineations of the pigeon MRI brain atlas [38]. The entopallium and the visual Wulst are primary visual telencephalic areas with thalamotelencephalic input from the visual tecto-and the thalamofugal systems, respectively.…”

“…Activations induced in awake pigeons by the visual stimuli (vs. rest) per individual. The statistical parametric maps (unilateral one sample t-test) are superimposed on anatomical images coming from the high-resolution pigeon atlas [38]. They illustrate the bilateral activation of the telencephalic entopallium (E).…”

In vivo measurement of T1 and T2 relaxation times in awake pigeon and rat brains at 7T

“…The inverted transformation matrix was used to transfer the ROIs from atlas space into an anatomical image. Ten regions, defined based on the pigeon brain MRI atlas , were selected bilaterally: entopallium (E); nucleus geniculatus lateralis pars dorsalis (GLd); hyperpallium apicale, including interstitial nucleus of the hyperpallium apicale (HA); hyperpallium intercalatum and hyperpallium dorsal (HI‐HD); field L; arcopallium (Arc); striatum (S); amygdala (Am); hippocampus (H); and ventricle (V).…”

Modulating Motor Behaviors by Electrical Stimulation of Specific Nuclei in Pigeons

“…Pigeons have outstanding abilities for long-distance flying, load carrying, and homing, which make them an ideal animal model for flying bio-robots. Furthermore, pigeons have been used as an animal model in behavioral neuroscience studies for many years; thus, the anatomy of their central nervous system in brain atlases [17,18] , as well as the connections between different brain regions [19][20][21][22] are well established. Although locomotive patterns of taking-off and turning are activated in pigeons via electrical stimulation of implanted electrodes in the thalamic nucleus dorsalis intermedius ven-tralis anterior (DIVA) and archistriatum, it is most likely that mechanisms for movement are behind the feelings of fear and pain [12] .…”