How do anxiety disorders manifest themselves in the brain?

[Bare_head]

Hey guys.

I am wanting to know if anyone has any information on how anxiety disorders manifest themselves. Anyone has any links or useful info.

I know that anxiety disorders can have a number of factors so im looking more at what brain chemicals and receptors are known to work/ be affected from said anxiety disorders.

Thanks

 

[plumbus-nine]

The "gold standard" of anxiety medicines, the benzos, work by increasing inhibitory GABAergic transmission as positive allosteric modulators. Pregabalin induces an enzyme which converts excitatory glutamate to GABA. Yet I'm not sure whether we have solid evidence that anxiety necessarily means to have too much excitation going on as somebody without anxiety will not need to get anxious from a little bit more excitation, only (?) at toxic levels there will probably always be anxiety and tension ...

Of these BZDs only alprazolam really worked for me, the others are hypnotic at the required dose.
The most effective and clear headed anxiolytic I've ever had was a very very low dose of O-PCM. Curiously, this won't be inhibitory but somehow shifting brain activity.
The second effective might have been memantine. It's a dopaminergic, which are said to be anxiogenic. Even the correct low dose of amph can be anxiolytic to me.

To me anxiety, the kind of which we deal with in clinics, is learned* Memory inhibitors can make good anxiolytics as well as antidepressants (a rat who doesn't remember a sec ago will swim infinitely in forced swim test) but aren't usable in humans. So usually it's some sort of compromise between bad and helpful effects, like with H1 antihistaminergics.

An atypical one is buspirone, a 5ht1 partial agonist which fails in almost everybody. Full agonists are said to be anxiolytic after a while but will acutely induce anxiety. 5ht2b is unfortunately little researched, as we know it can do both, be anxiolytic as well as heavily panic inducing. Other receptors I'll leave for others now

* but that about learning might be your real question?

 

[thegreenhand]

Plumbus gave a good neurochemical explanation but personally I find generalized the function of neurotransmitters to be too difficult to pin down so it’s never as easy as change chemicals —> change brain

neuroanatomy would tell us that it’s almost certainly overactivation of the amygdala and also potentially the nucleus accumbens. But that doesn’t do much good in helping you to treat it, if that’s why you’re asking

 

[plumbus-nine]

I find generalized the function of neurotransmitters to be too difficult to pin down so it’s never as easy as change chemicals —> change brain

neuroanatomy would tell us that it’s almost certainly overactivation of the amygdala and also potentially the nucleus accumbens. But that doesn’t do much good in helping you to treat it, if that’s why you’re asking

Yeah, I agree. Was talking more about isolated fears like social anxiety etc. which are learned and to which anxiolytics tend to chronically fail. Also anxiolytics are more inhibition lowering agents imho.

So you condition your amygdala to be more active, or certain stimuli to do this? Can you ever really reverse this or only learn strategies to go around / deal with?
Isn't the amygdala generally the center for emotions of so to speak (positive/negative)?

 

[Snafu in the Void]

There are obviously types of anxiety.

Take introverted people. Their brain is much more highly sensitive to their environment which then manifests as anxiety.

Ever wonder why some people 'flinch' more than other people? Its not fear. Their brain is just better at seeing it coming and reacting, they are more in tune with their environment.

Slightly off topic random 2 cents

 

[thegreenhand]

Can you ever really reverse this or only learn strategies to go around / deal with?

The brain is always plastic

Isn't the amygdala generally the center for emotions of so to speak (positive/negative)?

The literature is constantly being added to yeah it’s involved with emotions. But there are so many other structures too that are involved in emotions (and fear and anxiety) that it’s tricky to pinpoint things like that to one part of the brain. I mentioned it because it does seems to be heavily associated with fear but saying that it’s the “center” I think is not quite true

 

[plumbus-nine]

Feel this is relevant too (from wikipedia about norepinephrine):

The most important source of norepinephrine in the brain is the locus coeruleus, which contains noradrenergic cell group A6 and adjoins cell group A4. The locus coeruleus is quite small in absolute terms—in primates it is estimated to contain around 15,000 neurons, less than one-millionth of the neurons in the brain—but it sends projections to every major part of the brain and also to the spinal cord.[28]

The level of activity in the locus coeruleus correlates broadly with vigilance and speed of reaction. LC activity is low during sleep and drops to virtually nothing during the REM (dreaming) state.[29] It runs at a baseline level during wakefulness, but increases temporarily when a person is presented with any sort of stimulus that draws attention. Unpleasant stimuli such as pain, difficulty breathing, bladder distension, heat or cold generate larger increases. Extremely unpleasant states such as intense fear or intense pain are associated with very high levels of LC activity.

 

[Gaffy]

No brain is same

 

[Bare_head]

Thanks alot guys i guess im slowly learning its something i seem to cant shift and i reaļly want to fight it. But without any chemicals will probably the best ans safest approach.

I have never given ssri's a chance but tbh those things always put me off. Anything that munts lsd or mdma ferls scary too me.

Plumbus' account of O-PCE is interesting. Why do these types help making you "calm" in some cases and manic in others?

Can set and setting play a part? They are psychedelics afterall