The Thalamus - The Kernel in Your Mind

corbettw writes "This article on Yahoo Science News describes a new finding that explains how the thalamus is used by your brain to essentially boot your brain, and provide for central processing and control of all impulses going to and from the cortex. The article describes its function as an operating system, but from the description it actually seems closer to the functions of a kernel." From the article: "The finding, published last week in the journal Neuroscience, changes the way scientists understand nitric oxide's role in the brain, and it also has them rethinking the function of the thalamus, where it is released. The thalamus was thought to be a fairly primitive structure, sort of a gate that could either open and allow sensory information to stream into the cortex, the higher functioning part of the brain, or cut off the flow entirely. Godwin says the new research shows it's more accurate to think of the thalamus not as a gate but as a club bouncer, who doesn't simply allow a huge rush of people to go in or no one at all, but picks and chooses whom to let in and out. "

Comments

I can think it now.

[suso]

it's more accurate to think of the thalamus not as a gate but as a club bouncer, who doesn't simply allow a huge rush of people to go in or no one at all, but picks and chooses whom to let in and out. "

Thalamus: Whoa buddy, you can't go in.
Neuron: But, I'm with her!
Thalamus: Her? Yeah right!
Neuron: Cortica! Cortica! Come back! We can be together!

[meanwhile in the real world]

John: Hey Bobby, catch... whoa, heads up!
Bobby: Owwww!

The "yeah, but does it run Linux" department

[krell]

"the thalamus is used by your brain to essentially boot your brain"

Which now raises hope for those of us who want dual-boot flexibility.

Re:The "yeah, but does it run Linux" department

[Jerf]

Which now raises hope for those of us who want dual-boot flexibility.

So are you saying you're bi-curious?

Like the Internet?

[MECC]

FTP:"Your Brain Works Like the Internet"

A collection of pipes moving pr0n around?

Godwin?

[computational super]

Godwin says the new research shows it's more accurate...

But then they drifted off topic and started arguing about Nazis and Hitler and the discussion had to be ended.

From: Andy T.

[ettlz]

From: Andy T.
To: The Almighty

I still maintain the point that designing a monolithic kernel in -3000 BC is a fundamental error.
Be thankful you are not my student. You would not get a high grade for such a design :-)

Re:From: Andy T.

[daveed]

-3000 BC. That's like 1000 years in the future man!

My brain kernel's just fine...

[Flashpot]

but i'm paging out to my liver!

The better question is, what do we call it?

[s20451]

From the summary:

The article describes its function as an operating system, but from the description it actually seems closer to the functions of a kernel.

Does this mean we should call the brain the Brain/Thalamus? It's unfair to give the entire package precedence over the kernel, as one is useless without the other.

Re:The better question is, what do we call it?

[MillionthMonkey]

Does this mean we should call the brain the Brain/Thalamus? It's unfair to give the entire package precedence over the kernel, as one is useless without the other.

I used to study neuroscience. The thalamus is a HUGE bank of relay switches in the brain- all these trunk cables go into it from all over. Basically anything you're paying attention to involves some circuit going through the thalamus, and the way the thalamus works is what limits your ability to focus on multiple things at once. Once something becomes rote- like QWERTY typing or good guitar playing- the thalamus is no longer involved.

I have epilepsy- really bad seizures- and my brain gets really messed up on restarts because it regains function piece by piece. Occasionally I'll be totally conscious (forming some long term memories again), and watching stuff come back online- I can hear, then I can see, then I can recognize things I see, etc. There are intermediate states where I can see but not recognize things. The seizures start in the right temporal lobe, so the right hemisphere is completely screwed up, but if my left brain works I can compensate with higher functions. Usually I'm looking for water fountains because my head is really hot and sweaty after a seizure. I'll find a water fountain and think, is this a water fountain? Well it has a stream of stuff that looks drinkable... it has a thing coming out the side that you can turn... it MUST be a water fountain! I almost pissed on my wife's chair once after somehow figuring it was a toilet. But without thalamic activity I'd never be able to patch right brain functions and send sensory information to the forebrain from the left side. If I'm able to pay attention to something at all, then there is some thalamic function. Recognizing it is a different task.

The ability to form long term memories comes later and is a more distributed gradual process as areas of the cortex recover. I was in this cubicle working once... doing simple stuff like cleaning up someone's crappy code... then I started doing more mentally intense work, and I turned around after an hour or two and noticed my cubicle was a mess. Everyone said, "you had a seizure a few hours ago, don't you remember?"

Recently my brain has been passing through a metastable fugue state after really nasty seizures where I have partial function, but it's not me yet- it's like someone else. I answer yes/no questions completely differently, I don't recognize my wife, I fight with people if they get in my way, and I don't know where I'm going but I'm going somewhere, sometimes out the door. Usually no new memories are being formed; I have to go by what people tell me afterward. Apparently I'm getting better at fooling people in the fugue state because my speech in the fugue is starting to almost sound normal even though I have only partial brain function. One of these days I'm going to regain consciousness in jail.

Research abstract

[FleaPlus]

I really wish submitters would include a link to the research paper, so we could actually judge the research for ourselves instead of relying on some journalist's interpretation. Here's the abstract for this paper, from Neuroscience:

Diurnal gene expression patterns of T-type calcium channels and their modulation by ethanol

The transient (T-type) calcium channel participates in the generation of normal brain rhythms as well as abnormal rhythms associated with a range of neurological disorders. There are three different isoforms of T-type channels and all are particularly enriched in the thalamus, which is involved in generating many of these rhythms. We report a novel means of T-type channel regulation in the thalamus that involves diurnal regulation of gene expression. Using real time polymerase chain reaction we detected a diurnal pattern of gene expression for all T-type channel transcripts. The peak of gene expression for the CaV3.1 transcript occurred close to the transition from active to inactive (sleep) states, while expression for both CaV3.2 and CaV3.3 peaked near the transition of inactive to active phase. We assessed the effect of chronic consumption of ethanol on these gene expression patterns by examining thalamic tissues of ethanol-consuming cohorts that were housed with the controls, but which received ethanol in the form of a liquid diet. Ethanol consumption resulted in a significant shift of peak gene expression of approximately 5 h for CaV3.2 toward the normally active phase of the mice, as well as increasing the overall gene expression levels by approximately 1.7-fold. Peak gene expression was significantly increased for both CaV3.2 and CaV3.3. Measurements of CaV3.3 protein expression reflected increases in gene expression due to ethanol. Our results illustrate a novel regulatory mechanism for T-type calcium channels that is consistent with their important role in generating thalamocortical sleep rhythms, and suggests that alterations in the pattern of gene expression of these channels could contribute to the disruption of normal sleep by ethanol.

Curiously, I get the impression that the emphasis of the research is somewhat different from what was emphasized in the popular-press article.

Re:Research abstract

[mspohr]

Thanks for posting this abstract and link. Most articles in the popular press are written by idiots so it's good to go to the source.

From the abstract, it appears that the thalamus does act as a kind of "pacemaker" (or "motivator" as in R2D2).

The really important finding of the study is that this may be the path that alcohol uses to disrupt sleep.

Re:Research abstract

[phystor]

As a neuroscientist I completely agree that it would be useful to present at least some simplified version of the actual findings instead of some nifty computer analogy to make it sound cool. The actual findings are in stark contrast what is being claimed by the news piece.

The paper you link is a different one. This is the actual paper:

Alexander GM, Kurukulasuriya NC, Mu J, Godwin DW. Cortical feedback to the thalamus is selectively enhanced by nitric oxide. Neuroscience. 2006 Jul 28 http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=p ubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=168 76956&query_hl=12&itool=pubmed_docsum

Indeed the area they study is somewhat mysterious: The thalamus provides separate communication channels for essentially all sensory information from the sensory organs (e.g. eyes) to the cerebral cortex. However, unlike most brain areas it appears that there is no transformation going on in the thalamus. So if there is no computation, it must be a relay! As much as much most neuroscientist find the idea of pure "relay" unsatisfactory we simply have no evidence for anything beyond it. Hence all the speculation. Unfortunately, the present paper sheds no light onto the thalamus mystery. The authos cut a slice out of a brain and study in isolation. Clearly you won't get much functional information about what's actually going on in this way. Then the authors dump a drug onto the slice to show that it differentially turns up the gain of one input and turns down the gain of another one. Nice, but we don't know if this is actually going on in the brain or how this chemical would get there. If --as the journalists claim-- this finding were to transform our ideas about the thalamus then it probably wouldn't be published in a third tier journal like 'Neuroscience'.

So much for science journalisms.

-phystor-

Scary even to think about this

[roman_mir]

I don't know if I can trust any kernel to be compared to the brain, after all Windows gets the Blue Scream of Death and the Linux gets Panic Attacks, DOS has to be rebooted often to modify memory management, Unix gets segmentation falls and bus errors. This is terrible news, I think I am just going to walk around in circles until I stop thinking about this... Damn! It's a deadlock forced by a race condition! I just want to go to sleep.