New answers tagged

1

An answer to this question could potentially be found in "Understanding Adolescent Brain Development and Its Implications for the Clinician" Thanks to research by Jay Giedd and colleagues at the National Institute of Mental Health, it has become clear that, during the adolescent years, the organization and functioning of the brain go through ...


0

TL;DR: There are many ways a neuron can change after a neural impulse happens including calcium influx, long term potentiation and depression, and G-protein coupled receptors. While not an exhaustive list by any means I'll give a brief summary of some mechanisms I know best. Calcium Entry There exist calcium channels that open in response to a variety of ...


1

Unfortunately, there is no way to know how many sodium channels are active (or even present) in one person's brain due to the extremely high variability of channel and neuron density in a population and the lack of methodology around quantifying total number of healthy active synapses (1). Diseases like epilepsy can occur due various points of the sodium ...


4

The center-surround structure is created by the horizontal connectivity of the horizontal cells (Periman et al., 2012) that receive input from multiple photoreceptors (Fig. 1). Fig. 1. Retinal patch showing the connectivity between a horizontal cell and photoreceptors. Source: Harvey Mudd College The horizontal cell passes on the congregate output to the ...


2

I would argue the all-or-none principle is a rule of thumb. It is generally true if voltage hits a certain threshold then there will be a action potential with the same amplitude regardless the strength of the stimuli. But as you point out with the logic gate example, the threshold is notoriously hard to define mathematically. Furthermore Action Potentials ...


1

It seems like you suffer from a misconception. "The left eye sees more of the left side of an object..." is not how distance perception works. Otherwise we wouldn't be able to estimate the distance from flat objects, such as traffic signs and shooting targets. The actual mechanism is parallax estimation, or Binocular disparity. In a nutshell, the closer an ...


2

Since you tagged this with neuroscience, I'm going to assume the two forms you see are these: The top one is what you might call the "no assumptions form". Temperature is left as a variable, T, and will have to be plugged in, and one will also have to plug in the gas constant (R), Faraday's constant (F), and the valence (z) of the ion (X) in question when ...


1

The term noise can mean a number of different (more or les related) things is used in a number of different fields such as signal processing, psychology and statistics. Outside of its context, it is impossible to say for certitude what you professors were referring to. The quotations below come from wikipedia > Communication noise, wikipedia > Statistical ...


1

The major hurdle for novel treatments to make it into humans is the assessment of its merits and added value over existing, proven treatments. And more importantly, the safety for humans has to be validated to a sufficient extent. The notorious from bench to bedside (Goldblatt & Lee, 2010) bottle neck. To answer your questions: Technically, going from ...


3

The vector used in this study is based on the herpes simplex virus genome (HSV). Wildtype HSV mainly infects sensory neurons. After infection, it resides in a latent state in the nervous systems of the host for a lifetime. The viral genome persists in the cell, without integrating into the host genome (Marconi et al., 2000). The article cited is devoid of ...


0

Cortical columns (also called minicolumns) are not limited to the somatosensory cortex. As shown in this paper (which discusses how the miniucolumns change in response to aging), it is also present in the associative cortex. However, it should be noted that "minicolumn" in this paper is defined as neurons that are close together and form a minimum spanning ...


2

The answer to your (excellent) question is a matter of definition, which has its roots in the 18th century. A cathode is the electrode where conventional positive current leaves a current source. Conventional current is positive, due to historic reasons. Around 1750, Benjamin Franklin described the flow of current between wool and wax after ...


1

However, upon reviewing these papers, it appears that the neurons were stimulated while still inside the tissue, but after the tissue had been sliced. However, this seems so absurd that I must be misreading it. You're not misreading it. I can't access the paper you refer to, but this is a standard way to measure the electrophysiological properties ...



Top 50 recent answers are included