Cortical and thalamic connectivity of occipital visual cortical areas 17, 18, 19, and 21 of the domestic ferret (<scp><i>Mustela putorius furo</i></scp>)

J of Comparative Neurology

Innocenti

Hilgetag

et al. 2019

Self Cite

The present study describes the ipsilateral and contralateral cortico‐cortical and cortico‐thalamic connectivity of the parietal visual areas, posterior parietal caudal cortical area (PPc) and posterior parietal rostral cortical area (PPr), in the ferret using standard anatomical tract‐tracing methods. The two divisions of posterior parietal cortex of the ferret are strongly interconnected, however area PPc shows stronger connectivity with the occipital and suprasylvian visual cortex, while area PPr shows stronger connectivity with the somatomotor cortex, reflecting the functional specificity of these two areas. This pattern of connectivity is mirrored in the contralateral callosal connections. In addition, PPc and PPr are connected with the visual and somatomotor nuclei of the dorsal thalamus. Numerous connectional similarities exist between the posterior parietal cortex of the ferret (PPc and PPr) and the cat (area 7 and 5), indicative of the homology of these areas within the Carnivora. These findings highlight the existence of a frontoparietal network as a shared feature of the organization of parietal cortex across Euarchontoglires and Laurasiatherians, with the degree of expression varying in relation to the expansion and areal complexity of the posterior parietal cortex. This observation indicates that the ferret is a potentially valuable experimental model animal for understanding the evolution and function of the posterior parietal cortex and the frontoparietal network across mammals. The data generated will also contribute to a connectomics database, to further cross‐species analyses of connectomes and illuminate wiring principles of cortical connectivity across mammals.

Section: Area Ppc Connectivity-ferret Versus Catsupporting

confidence: 88%

Section: Connectivity Patterns Of Parietal Areas Of the Ferret And mentioning

confidence: 86%

Cortical and thalamic connectivity of posterior parietal visual cortical areas PPc and PPr of the domestic ferret (Mustela putorius furo)

J of Comparative Neurology

Innocenti

Hilgetag

et al. 2019

Self Cite

“…The posterior parietal cortex has been identified as an integral component of the visual dorsal stream, maintaining direct connections with the prefrontal cortex, as well as numerous direct and indirect connections with the occipital cortex. This has been illustrated in numerous animal studies (Baizer, Ungerleider, & Desimone, 1991;Kaas & Stepniewska, 2016;Remple, Reed, Stepniewska, Lyon, & Kaas, 2007) as well as in the ferret (Dell et al, 2018a(Dell et al, , 2018b. Similarly, the visual temporal cortex is integral to visual ventral stream information processing; thus, direct connections with the prefrontal cortex are anticipated (Cloutman, 2013;Goodale & Milner, 1992;Webster et al, 1994) The current study shows that areas 20a and 20b are well connected with PMLS (Figures 4-5, 7, and 9; Table 1), a feature also observed in the cat (Symonds & Rosenquist, 1979).…”

Section: Interaction Of the Dorsal And Ventral Streamssupporting

confidence: 80%

“…Note the dense connectivity with most regions of the visual thalamus, apart from that to the C lamina of the lateral geniculate nucleus and the MIN. Conventions and abbreviations as provided in the legend to Figure 6 and abbreviation list areas of the ferret are under a stronger influence of lateral geniculate input compared to the cat, potentially emphasizing differences in the extraction of visual information in the two species possibly related to life history and morphological differences (Dell, Innocenti, Hilgetag, & Manger, 2018a;Dell, Innocenti, Hilgetag, & Manger, 2018b).…”

Section: Resultsmentioning

confidence: 99%

Cortical and thalamic connectivity of temporal visual cortical areas 20a and 20b of the domestic ferret (Mustela putorius furo)

J of Comparative Neurology

Innocenti

Hilgetag

et al. 2019

Self Cite

The present study describes the ipsilateral and contralateral corticocortical and corticothalamic connectivity of the temporal visual areas 20a and 20b in the ferret using standard anatomical tract‐tracing methods. The two temporal visual areas are strongly interconnected, but area 20a is primarily connected to the occipital visual areas, whereas area 20b maintains more widespread connections with the occipital, parietal and suprasylvian visual areas and the secondary auditory cortex. The callosal connectivity, although homotopic, consists mainly of very weak anterograde labeling which was more widespread in area 20a than area 20b. Although areas 20a and 20b are well connected with the visual dorsal thalamus, the injection into area 20a resulted in more anterograde label, whereas more retrograde label was observed in the visual thalamus following the injection into area 20b. Most interestingly, comparisons to previous connectional studies of cat areas 20a and 20b reveal a common pattern of connectivity of the temporal visual cortex in carnivores, where the posterior parietal cortex and the central temporal region (PMLS) provide network points required for dorsal and ventral stream interaction enroute to integration in the prefrontal cortex. This pattern of network connectivity is not dissimilar to that observed in primates, which highlights the ferret as a useful animal model to understand visual sensory integration between the dorsal and ventral streams. The data generated will also contribute to a connectomics database, to facilitate cross species analysis of brain connectomes and wiring principles of the brain.

“…Furthermore, these mammals display complex behavior, are inexpensive to house and have a short gestation period as well as a limited life time, making them an attractive 'whole lifespan model' (Fox, 1998) . Recently established extensive tract-tracing connectivity data of the ferret (Dell, Innocenti, Hilgetag, & Manger, 2019a, 2019b, 2019c have made it possible to compare anatomical cortical connectivity with that reported by tractography methods. Thus, the present study aimed to use the ferret as an animal model to assess the performance of six diffusion tractography algorithms compared to histological tract-tracing data from the occipital, parietal and temporal cortices in the ferret.…”

Section: Introductionmentioning

confidence: 99%

Comparison between diffusion MRI tractography and histological tract-tracing of cortico-cortical structural connectivity in the ferret brain

Delettre

Messé

et al. 2019

Preprint

The anatomical wiring of the brain is a central focus in network neuroscience. Diffusion MRI tractography offers the unique opportunity to investigate the brain fiber architecture in vivo and non invasively. However, its reliability is still highly debated. Here, we explored the ability of diffusion MRI tractography to match invasive anatomical tract-tracing connectivity data of the ferret brain. We also investigated the influence of several state-of-the-art tractography algorithms on this match to ground truth connectivity data. Tract-tracing connectivity data were obtained from retrograde tracer injections into the occipital, parietal and temporal cortices of adult ferrets. We found that the relative densities of projections identified from the anatomical experiments were highly correlated with the estimates from all the studied diffusion tractography algorithms (Spearman's rho ranging from 0.67 to 0.91), while only small, non-significant variations appeared across the tractography algorithms. These results are comparable to findings reported in mouse and monkey, increasing the confidence in diffusion MRI tractography results. Moreover, our results provide insights into the variations of sensitivity and specificity of the tractography algorithms and hence, into the influence of choosing one algorithm over another.