/sci/ - Science & Math

>>5043289
I'm a neuro Ph.D student, and my focuses are in systems-level physiology. Unfortunately, I do not have a very strong background in cell biology outside of neuron-specific function, and my background in genetics is population genomics.

If you're interested in how genome expression can be changed over time, look up stuff on promoters, acetylation, and histones. Wiki is a good starting point most of the time.

>>5043269
No, but it makes you think differently. More precisely, it makes you behave differently. These types of things are often studied in the hippocampus, a structure known for its role in learning and memory.

>>5043263
Any time. Neuroscience rules.

>>5043239
Surely. I'll explain how synaptic plasticity works as best I can.

Neurons have very close "connections" with one another called synapses, which are sites where one neuron can discharge chemicals (neurotransmitters) onto another neuron. Presynaptic neurons are neurons releasing transmitter, postsynaptic neurons are neurons receiving transmitter. The most common effect of neurotransmitters is to cause a flux of ions into the postsynaptic cell, thereby changing the overall charge of the cell. When the cell reaches a certain positive charge, it fires an action potential and communicates with further cells down the line.

Synaptic plasticity occurs when there are changes at the synapse (usually on the postsynaptic side) that change the effect that a presynaptic action potential has on the postsynaptic cell, usually by increasing or decreasing the effect. For example, in sea slugs, when you poke them they get upset and squirm. Over time, if you keep poking the slug, the number of receptors for neurotransmitters in the neuron connected to the slug's muscle will actually decrease, thereby decreasing the overall effect that activity in the neuron presynaptic to that has on the neuron, and therefore decreasing the effect that the neuron has on the muscle, and therefore reducing overall behavioral response in the slug.

I typed all of that quickly with nearly no regard for it's transparency, so I hope that it's okay.

>>5043229
Look up NMDA/Calmodulin dependent plasticity. It's in just about every undergrad neuro textbook (Kandel's Principles of Neural Science is a good one).

The short of it is that local calcium signaling cascades in dendritic spines can cause the insertion of more AMPA receptors into the postsynaptic density, increasing the depolarization of a single presynaptic action potential by increasing the permeability of the membrane to cations, and therefore increasing the synaptic current induced by the action potential. For those of you who are computationally minded, this is the same as increasing the edge weight between the two neurons.

All of this occurs entirely locally. mRNAs for AMPARs are shuttled to synaptic spines, but this process does not require a change in the expression of mRNAs in order to work. If it did, learning would be much much slower.

>>5043194
You can have a change in synaptic physiology with absolutely no change in the distribution of promoters or histones on the genome. Behavior cannot be entirely reduced to epigenetics.

I sure did.

Just take a few upper division biology courses and major in math/physics. Learning the bioscience down the line is easy, learning the physics/math is not.

>>5023845
It was indeed the introductory physiology course.

>>5023804
They made a pretty big deal about it in lectures and gave us copious practice problems. I'd be amazed if someone actually did that.

Then again, the attached image suggests that some people had scores between 8 and 12, which is about half the score you should expect for bubbling in "A" for every question...

>>5023746
Hence the 33%.

>>5023783
I thought the professor was brilliant and an excellent lecturer, but he was a complete asshole and wrote tests like the above. Still, I'd say shitty students - I scored a 68% on that exam which was 95th percentile.

Real biology problems.

The average on this test was a 33%, btw.

>>5023474
It's better to read science journalism forever than to receive little or no exposure to science. For a high schooler or even a first year uni student, something like "man that chemistry image macro was much more interesting than that shakespeare one..." is enough of a push to add a science course or two to a schedule, which is where most careers in science begin.

Also, as a scientist, it pleases me tremendously when my family and friends show interest in any kind of non-technical science literature. It's much better to have an interested public that's receptive to science and science funding than to have a bunch of totally ignorant conservatives who think the NIH and animal research is useless.

>>5020444
I made a similar joke to some faculty on orientation day and got some chuckles.
But seriously, expect us.

>Age:
22
>Country:
U.S.
>Job:
Ph.D Student (Neuroscience)
>School:
Yale
>Computer:
Custom built desktop and Asus laptop
>OS:
Windows 7 and Windows 7. I have a mint partition but it isn't useful to me.
>Dream Job:
Provost, tenured faculty

There's also fewer ethical limitations for working with rodents than with primates - you don't even have to be sterile to perform neurosurgery on a mouse, but you have to be sterile if you're even going to touch the inside of a macaque recording chamber. No IRB cares about rodent lesion work, but monkey lesion work is very very difficult to get approved

>>5002132
The 1950s called, they want to tell you about experimental economics.

>>5002087
This is a completely arbitrarily ranked list of vastly overlapping disciplines. Can you try to justify this, please?

Techniques in psychology (particularly perceptual psychophysics) and economics (particularly microeconomics and game theory) have made the only real strides in understanding the behavioral significance of cortical and subcortical brain regions possible. Primate neurophysiology would be nothing without a psychometric function or a utility function. The random dot motion task used to study lateral intraparietal, FEF/SEF and V4? You can thank psychologists for that.

Even purely behavioral studies are useful to neuroscience. Case in point: last week's jneurosci featured a paper that predicted properties of saccades using economic intertemporal value functions. That's a paper in a (very very good) neuroscience journal that had nothing but eye position data, and used economic and psychological models to characterize it.

I have nothing to say about sociology, though.

The second one will be more valuable for a physics degree. With a background in programming, python can be learned in two days.

>>4970041
Any reinforcement learning algorithm can also learn to predict events of a given environment over time. Just because some biological organisms are especially good at it doesn't give them a special property (a soul, consciousness, etc).

I say this in fear of opening the can of worms that is machine consciousness.

Firstly OP, a little nomenclature: a Neurologist is a medical doctor who specializes on neuropathology. You want a neuroscientist. Neuroscientists and neurologists are overlapping, but not equal, sets. One is also not a subset of the other.

You can stimulate sensation or motion in the fingers with an electrical impulse to the appropriate area of somatosensory or motor cortex (brodman 3 and 4 respectively), so an impulse to an appropriate part of the brain can induce sensation or behavior. An impulse to the frontal eye field (between 4, 6 and 8) can induce a saccade in the direction of the receptive field of the neuron you stimulate, which is likely more pertinent to your question. You can also induce saccades with stimulation of lateral intraparietal, and secondary eye field. Whether or not this would direct your attention to the target of your saccade depends on your definition of attention.

I don't see how this is related to consciousness, though. Mostly because consciousness has no meaningful/non-trivial definition.

Grad school, cell phoned. My undergrad advisor did not have a cell because he did not always want to be reachable.

He also constantly had 200 unanswered emails in his gmail inbox.

Firstly OP, /sci/ is not a population of people whose definition of science is consistent or even explicit.

Most biology uses the scientific method. However, biology, like *any* science, is a field in which not all questions are created equally. Some fields of biology are entirely mathematically rigorous (biophysics and structural biology, pharmacology, etc), whereas other fields are not so.

There is still influential mathematical work in Biology in all fields. The work of William Bialek at Princeton and Xiao-Jing Wang at Yale are two profound examples of researchers who applied mathematics to make precise predictions about the actual parameters of biological systems, and the 'breaking points' of the same systems.

tl;dr anyone who tells you that there is no mathematics in biology is likely basing their judgement on the content of undergrad classes, and is clearly not familiar with the literature.

>>4963624
Hello, stonypal.