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Abstract The lateral prefrontal cortex (LPFC) is an evolutionarily expanded region in humans that is critical for numerous complex functions, many of which are largely hominoid specific. Although recent work shows that the presence or absence of specific sulci in anterior LPFC is associated with cognitive performance across age groups, it is unknown whether the presence of these structures relates to individual differences in the functional organization of LPFC. To fill this gap in knowledge, we leveraged multimodal neuroimaging data from two samples encompassing 82 young adult humans (aged 22–36 years) and show that the dorsal and ventral components of the paraintermediate frontal sulcus, or pimfs, present distinct morphological (surface area), architectural (thickness and myelination), and functional (resting-state connectivity networks) properties. We further contextualize the pimfs components within classic and modern cortical parcellations. Taken together, the dorsal and ventral pimfs components mark transitions in LPFC anatomy and function, across metrics and parcellations. These results emphasize that the pimfs is a critical structure to consider when examining individual differences in the anatomical and functional organization of LPFC and suggest that future individual-level parcellations could benefit from incorporating sulcal anatomy when delineating LPFC cortical regions.
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The dorsal plate is a critical feature in the reassessment of the rotiferan genus Ptygura (Monogononta; Gnesiotrocha; Flosculariidae)
All species of Flosculariidae (Rotifera; Monogononta; Gnesiotrocha; Flosculariaceae) possess a flexible integument; they are termed illoricate. But species of four genera (Beauchampia, Floscularia, Limnias, and Ptygura) possess a distinctive hardened region on the dorsal side of their anterior end, which unfortunately has received little attention beyond the species level. In our work we study the ultrastructure of these hardened regions. In Beauchampia, Limnias, and some species of Ptygura the hardened zone takes the form of a dorsal plate (hereafter DP) with or without additional protruding processes. The DP has the shape of a ~50 μm diameter disc enfolding the anterior dorsal region of the animal, with a perimetral inward fold, smooth surface, and pores. The DP of Limnias ceratophylli shows three main ultrastructural differences from the rest of the body: (1) type of glycocalyx, (2) absence of small mounds on its surface, and (3) presence of broad cisternae at the base of the pores. In Floscularia and some Ptygura the hardened structures are reduced to a pair of dorsal projections protecting the dorsal antenna: i.e., lacking a full DP. These structures deserve attention because their adaptive importance has not been studied. Here we augment those observations with other characters: i.e., presence/absence of a birefringent body in late-stage embryos and morphology of their trophi and corona. Our goal was to provide information to help develop better taxonomy, as well as advance our understanding of the evolution of sessile taxa in general and of the potentially polyphyletic Ptygura genus in particular.
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- Award ID(s):
- 2051710
- PAR ID:
- 10496006
- Publisher / Repository:
- Magnolia Press
- Date Published:
- Journal Name:
- Zootaxa
- Volume:
- 5428
- Issue:
- 1
- ISSN:
- 1175-5334
- Page Range / eLocation ID:
- 107-123
- Subject(s) / Keyword(s):
- Rotifera Anatomy loricate morphology Ptygura sessile taxonomy
- Format(s):
- Medium: X Other: PDF
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.11646/zootaxa.5428.1.5
