15

The key point is that the brain is not a uniform structure. The outer layer, known as grey matter, is a relatively uniform and flat structure. Underneath the grey matter is white matter. An overly-simple characterization of these two areas is that grey matter performs computations, and white matter lets different areas of grey matter talk to each other. Here'...


13

First of all, the human brain is distinctively larger than that of any other primate, mainly due to the great expansion of the cerebral cortex. The underlying structures have remained relatively stable (Toro et al., 2008). As the cortex overlies the rest of the brain, a solution had to be found, because the whole brain did not have to inflate to increase ...


8

I'll tackle this question from a functional point of view. Gray matter are cell bodies, white matter are myelinated fiber tracts. In the brain, the gray matter is basically the cortex, the white matter lies mainly underneath it. The Cortex is the place where all the higher mental processing takes place (Fig. 1). Fig. 1. Cortical functions. Source: Penn ...


8

You are right that active adult neurogenesis is generally considered to be restricted to the dentate gyrus of the hippocampus, and the subventricular zone of the lateral ventricles. The latter generates neurons that subsequently migrate through the rostral migratory stream to the olfactory bulb to become interneurons (Ming & Song, 2011). Although the ...


7

Broca is generally considered the first person to localise structure to function, however, there are some earlier individuals to consider: EDIT: i recommend the chapter Neurolinguistics from the Middle Ages to the Pre-Modern Era: Historical Vignettes in: Stemmer, B. & Whittaker, H.A. (1998). Handbook of Neurolinguistics. Academic Press: London. it has a ...


7

The corpus callosum is a massive horizontal white matter tract (commissure) that connects the two hemispheres and it is considered the most important route of communication between the hemispheres. However, there are five additional commissures that cross the midline, namely: Anterior commissure, connecting the two olfactory bulbs and the temporal ...


7

As often the case, named after the person who first described it. From Encyclopedia Britannica: Wernicke area, region of the brain that contains motor neurons involved in the comprehension of speech. This area was first described in 1874 by German neurologist Carl Wernicke.


6

In the article you provided (Molofsky et al., 2014) the authors refer back to (Arber, 2012) and surprisingly, the term puncta is not used in the latter. So that's pretty much a dead end. I found another article (Ippolito & Eroglu, 2010) in which the authors do explicitly clarify their use of the word puncta. In this article, puncta is a term used in ...


6

Phineas Gage had his famous spike through the head in 1848, which lead to some discoveries about the function of that area, but these were quite general. See: Harlow, J. M. (1869). Recovery from the passage of an iron bar through the head. Clapp. But, Broca appears to be the first to identify a specific area: In 1861, the French surgeon, Pierre Paul ...


6

What is the difference in the brains for animals capable of these great differences in sexual activity and what part of the brain is responsible for this? In my opinion is a matter of creativity and curiosity. Evolved species try to interact with their ambient in unusual ways, testing different approach to the same "problem" not only to satisfy primary ...


5

There is no evidence that the CSF has a pump. A link to a Chiropract Medicine page (a good one, from my reading) tells us that: It is something of a misnomer to speak of CSF “circulation,” particularly in the spinal canal, as there is no continuous loop circulation of CSF as in the cardiovascular system. [CEREBROSPINAL FLUID STASIS AND ITS CLINICAL ...


5

Interesting question! The paper you read should have inserted an appropriate citation. Moreover, "little input" is a subjective statement and doesn't make much sense in the context, as it can mean that there are few efferent axons (which may still have large effects on retinal functioning), or that the efferent input is relatively unimportant when compared ...


5

My answer to this question would be pretty straightforward. From a neurobiological standpoint, sex causes the release of various pair-bonding influencing hormones oxytocin, vasopressin and dopamine. These "feel good" hormones promote bonding and basically encourage the couple to stay together. The more the pair have sex, the more these hormones get ...


5

First, biological features do not always arise from some intrinsic benefit. They can also be byproducts of other adaptations, or spandrels. That being said, one example of a possible benefit is specialization. For instance, birds will develop asymmetries in their visual system based on light inputs to their outward-facing eye (one eye faces the eggshell, ...


5

Vesicle count and spine morphology are two of the better-known predictors of synaptic strength. But they are not the whole story. Glia, like astrocytes can also modulate synaptic strength by releasing their own neurotransmitter or co-agonist, but you need more than just images to detect that process. There is also the matter of receptor distribution in ...


5

There have been many proposed explanations for the condition. The explanation which seems to have gained traction states that an individual with Capgras syndrome experiences a "disconnect" between the part of the brain that recognizes faces and the part of the brain that processes emotion. Thus, the person may see someone who looks like his brother, but does ...


5

The neural substrates most involved in retrieval-induced forgetting (RIF) appear to be the anterior cingulate cortex (ACC), the dorsolateral pre-frontal cortex (DLPFC) and the ventrolateral pre-frontal cortex (VLPFC) (Bäuml, Pastötter and Hanslmayr, 2010). I will not pretend to one-up their concise summation of the evidence. The results are consistent ...


5

Biondi et al. (1998) compared MR images of monozygotic twins and found that while the brains of monozygotic twins are not identical, they are similar. Relevant for understanding the concordance rate of schizophrenia in monozygotic twins, Suddath et al. (1990) examined MR images of monozygotic twins who where discordant for schizophrenia. They found that the ...


5

Is it known whether the connection strength of synapses is important to the functioning of the brain or does just the binary existence of a synapse matter? I think it's safe to say that neuroscience, as a field, would stand behind this statement from neurobiologist David Sweatt, in his excellent 2003 (1st edition...2nd is probably even more current) ...


5

Short answer In complicated matters like neural connections in a layered cortex, it is all about semantics. One should carefully place statements in their context and deduce their meaning. Background In Fig. 1 a schematic of the layering of the cortex is shown. The layers can be separated based on their histological and neurophysiological features: Layer ...


5

There is a physical connection. Synapses are held together by adhesion molecules, like cadherins and neuroligins/neurexins. Missler, M., Südhof, T. C., & Biederer, T. (2012). Synaptic cell adhesion. Cold Spring Harbor perspectives in biology, 4(4), a005694.


5

As Wikipedia points out: Myelin is a lipid-rich (fatty) substance formed in the central nervous system (CNS) by glial cells called oligodendrocytes, and in the peripheral nervous system (PNS) by Schwann cells. When referring to the sheath, you are referring to the covering which is made of myelin. Myelin sheaths are sleeves of fatty tissue that ...


4

The brain stem comprises the medulla, the pons and the midbrain, according to Kandel's extremely authoritative Principles of Neural Science. This is equivalent to the midbrain and the hindbrain minus the cerebellum, which is probably where the confusion stems from. Kandel, E. R., Schwartz, J. H., & Jessell, T. M. (Eds.). (2000). Principles of neural ...


4

for the record, and as confirmation of what the above answers affirm regarding ancient times here is the abstract from a fairly recent historical review of the subject: Fragments of neurology can be found in the oldest medical writings in antiquity. Recognizable cerebral localization is seen in Egyptian medical papyri. Most notably, the Edwin Smith papyrus ...


4

According to Wikipedia: As predicted by the acquired brain injury literature, early PET studies have shown the task involves significant activation of the dorsolateral prefrontal cortex. However, more recent fMRI studies have shown that the ventrolateral prefrontal cortex together with the caudate nucleus may be the regions most important for the ...


4

Alien hand syndrome (AHS) is an extremely rare disorder. It is so rare, there appears to be no available prevalence studies. In the AHS literature, case studies are therefore nearly universal. For all intents and purposes, it is reasonable to say that AHS appears to be a disease so rare that the empirical prevalence rates are in every listed case ...


4

You could start with Hochner's papers, like this one: Hochner, B., Shomrat, T., & Fiorito, G. (2006). The octopus: a model for a comparative analysis of the evolution of learning and memory mechanisms. The Biological Bulletin, 210(3), 308-317. http://www.biolbull.org/content/210/3/308.full As far as I know, he is a world expert.


4

The human neocortex contains approximately 1.5x10^14 synapses, connecting its 19–23 billion neurons. Source: Pakkenberg, B., Pelvig, D., Marner, L., Bundgaard, M. J., Gundersen, H. J. G., Nyengaard, J. R., & Regeur, L. (2003). Aging and the human neocortex. Experimental Gerontology, 38(1-2), 95-99. doi:10.1016/S0531-5565(02)00151-1


4

I was interested in the same question a while ago. Unfortunately, Witelson et al (1999) reported here (http://penthai.sc.mahidol.ac.th/html/articles/newsletter/paper3.pdf) that volume measurements haven't been taken at the time. Weight data is available, but weight and volume aren't correlated perfectly. Witelson, S. F., Kigar, D. L., & Harvey, T. (...


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