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7

There is no such thing as "zero" activity in regards to brain circuits. Even when you record neurons from a brain slice in vitro, you have spontaneous network activity. There is a few studies that suggest that brain circuits are chaotic, where infinitesimal difference in the initial state will lead to exponentially diverging patterns of activity: ...


6

As far as I know, it is not possible for a neuron to change which type of neurotransmitter it releases. However, it is the case that the neurotransmitter GABA changes from excitatory to inhibitory over the course of development. This is occurs because GABA activates Cl- (chloride) channels. The chloride concentration gradient across the cell membrane ...


5

Although this paper is not grounded in neurobiology "Up speeds you down. Awe-evoking monumental buildings trigger behavioral and perceived freezing" by Joey et al. should be a good starting point for further research into the domain of environmental psychology with a focus on human-made environments. In the paper, subjects are shown to have slower reaction ...


4

The phenomenon you are referring to is called synesthesia, which can be defined as (Sinke et al., 2012): Synesthesia (Greek: syn = together; aesthesis = perception) is [...] a crossing of sensory perceptions, where stimulation within one sensory modality/stream leads to an internally generated perceptual experience of another sensory modality/stream. ...


4

Short answer On the basis of a cursory literature review, I conclude that Jospeh's observations were correct, but his conclusions that a callosotomy can result in a dual consciousness were far stretched. Background First off, I'm not an expert on this topic, but I will give my referenced opinion anyway, as there is no answer yet to this question; Below are ...


3

Based on computational models of resting brain activity, it can be assumed that the brain is a multistable dynamical systems that operates on the edge of a "critical" bifurcation point seperating a low firing spontaneous state (which can be seen as more or less random low firing activity) from a state of high frequency activity. see for example the work ...


2

Assuming you are talking about the ability of the visual system to resolve spatial detail (resolution, if you wish), then your question is on visual acuity as a function of eccentricity on the retina (Fig. 1). Due to the densely packed cones at the fovea (corresponding to the central field of view (FOV), see Fig. 1), visual acuity (VA) is the greatest at ...


2

Short answer The function of the thalamic adhesion in humans is unknown. Background The two halves of the thalamus are separated by the third ventricle. In about 80% of people, the thalami are connected via the thalamic adhesion (massa intermedia, Fig. 1), which mainly contains cell bodies, but also commissural fiber systems that connect some thalamic ...


2

In a recent study, brain scans revealed that people under the influence of LSD experience images through information drawn from many parts of their brains, and not just the visual cortex at the back of the head that normally processes visual information. While under influence, regions normally segregated spoke to one another. Further images showed that other ...


2

A nice illustrative image of how the photoreceptors connect to the retinal ganglion cell (RGC), and thereby facilitate the center-surround structure is provided in figure 1 below. It shows a cross section through the retina. Fig. 1. Photoreceptor organization and connections to the retinal ganglion cell. source: McGill University The receptive fields ...


2

...studies that show that every part of the cortex does essentially the same thing! I would be much interested in seeing these studies - Although the brain is plastic and inter-individual differences can be substantial, it is generally accepted that functional regions are well defined in terms of their anatomical locations and brain mapping was, and ...


2

Synapses likely change their strengths based on a form of spike-timing-dependent plasticity. Is this true for all types of synapses in all parts of the human brain? No, not all. For example, there is frequency-dependent-plasticity, where the firing frequency of the pre-synaptic cell will change the synaptic strength. In Nikolaev, et. al. (2013), ...


1

A receptive field is often functionally characterized by electrophysiological experiments. During these experiments, a certain area of the body is stimulated (e.g., a certain part of the visual field is illuminated, or a certain area o the skin is haptically stimulated, etc.). Then it is determined if a neuron shows a response, either a stimulation ...


1

According to "Tightly coupled brain activity and cerebral ATP metabolic rate" which is summarised in the Scientific American article "Why Does the Brain Need So Much Power?", conscious computation accounts for 50% of the brain's power consumption. From the Scientific American article: Chen and his colleagues used MRS specifically to track the rate of ...


1

Joseph's description of his patients fascinated me. The concept of two minds fighting for control isn't a new one to me, but was previously restricted to science fiction and/or horror genres. How strange to find a real-life example of it. What I find unsatisfying about the explanation of "reduced inhibitory control of the dominant hemisphere over the ...


1

I wanted to make a few additions to Christiaan's answer. First of all, the functional location's as described by Brodmann (wiki) is a little outdated. Nowadays, it is believed that there are networks of regions that are responsible for a particular function. An example is the default mode network, a network of the ACC and prefrontal regions, that is ...



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