Structural MRI has found that human brains are larger than chimpanzee brains due to increased and continued brain growth velocity in utero. PET imaging has found similarities between humans and macaque monkeys in the activation of language areas of the brain when listening to species-specific vocalizations. Functional MRI has found differences in the connectivity patterns of macaques and humans; however, the capability of fMRI is limited by its sensitivity to head movement. Diffusion-weighted imaging found that white matter integrity peaks and declines relatively earlier in humans than in chimpanzees. While these techniques have helped discover what changes have occurred in the brain between primates and humans, changes in policies of using primates in research present limitations. Understanding the vertebrate and human brain is a complex task. The best approach, as shown by these papers, is to compare the brains of multiple vertebrate species and use new technologies to identify what changes have occurred in the brain and understand when, how, and why they happened. Complete execution of the approach is difficult, however, due to extinct species, technology limitations, and limited access to research subjects, as explain by the papers. With these limitations, the question arises of whether complete understanding of the vertebrate brain will ever be
Structural MRI has found that human brains are larger than chimpanzee brains due to increased and continued brain growth velocity in utero. PET imaging has found similarities between humans and macaque monkeys in the activation of language areas of the brain when listening to species-specific vocalizations. Functional MRI has found differences in the connectivity patterns of macaques and humans; however, the capability of fMRI is limited by its sensitivity to head movement. Diffusion-weighted imaging found that white matter integrity peaks and declines relatively earlier in humans than in chimpanzees. While these techniques have helped discover what changes have occurred in the brain between primates and humans, changes in policies of using primates in research present limitations. Understanding the vertebrate and human brain is a complex task. The best approach, as shown by these papers, is to compare the brains of multiple vertebrate species and use new technologies to identify what changes have occurred in the brain and understand when, how, and why they happened. Complete execution of the approach is difficult, however, due to extinct species, technology limitations, and limited access to research subjects, as explain by the papers. With these limitations, the question arises of whether complete understanding of the vertebrate brain will ever be