Posts Tagged 'geometric morphometrics'

Brain landmarks

Chollet et al 2014There is an interesting analysis by Madeleine Chollet and colleagues on brain landmarking. They analyzed and quantified intra- and inter-observer error when collecting coordinates from 3D digital brains. Results are encouraging, evidencing average errors of 1.9 and 1.1 mm, respectively. However, values are much variable, depending upon the specific brain area. Generally, midsagittal landmarks show less uncertainty than parasagittal ones, and subcortical landmarks are more reliable than cortical ones (good for me: that’s why most of my papers are on midsagittal and subcortical morphology!). The analysis has been performed only on 10 specimens, and larger samples can surely add to the current results. Furthermore, in this study only the left hemisphere has been considered, in which sulci and gyri are generally easier to recognize. Despite these limits, the paper supplies clear results and useful comments. These kinds of analyses are necessary to promote quantitative perspectives in landmark-based morphometrics. For an excellent example of quantitative approach in paleoneurology I recommend to see the article by Simon Neubauer and colleagues on australopiths’ brain size estimations.

More asymmetries

Gomez-Robles et al 2013Cerebral asymmetries are a thorny issue in both paleoneurology and human neuroanatomy: despite their relevance, their origin and actual variations are elusive. Conceptual and technical problems tend to hamper conclusive statements, as evidenced by the many disagreements and uncertainties in the field. A recent paper on asymmetries in human and chimpanzee brains has added a geometric perspective to the topic. This shape analysis suggests that humans and chimpanzees have the same kind of asymmetries, with humans showing a larger degree of variation and expression of those patterns. Hence, again it seems it is more a matter of grade than of novel characters, at least in terms of geometry. Interestingly, allometry has a very minor role (if any) in intraspecific differences. In both species, shape variation and asymmetries are especially marked in the parietal areas.


Enter your email address to follow this blog and receive notifications of new posts by email.

RSS Brain News

RSS Cognitive archaeology

RSS The Skull Box

  • Stáňa
    A new PhD student in the team working on craniovascular anatomy! Stanislava Eisová was in our laboratory few years ago, publishing a paper on parietal bone and vessels in which she investigated correlations between craniovascular morphology, skull size, and bone thickness. She got a Master Degree in Anthropology of Past Populations at the University of […] […]

RSS Anthropology

RSS Human Evolution

  • An error has occurred; the feed is probably down. Try again later.

RSS Neurophilosophy

  • Researchers develop non-invasive deep brain stimulation method
    Researchers at MIT have developed a new method of electrically stimulating deep brain tissues without opening the skullSince 1997, more than 100,000 Parkinson’s Disease patients have been treated with deep brain stimulation (DBS), a surgical technique that involves the implantation of ultra-thin wire electrodes. The implanted device, sometimes referred to as […]

Disclaimer

This blog publishes texts and comments of the author, which can not be referred to institutions or contexts outside of the blog itself. The published material may be partly derived or reported from the Web, and therefore evaluated in the public domain. If some content violates copyright or if it is considered inappropriate, please contact me, to promptly remove it. On the other hand, please cite this source whenever using images or texts from this website.