Study casts new light on the brain mechanisms behind recurrent bouts of intense anxiety
This is just one example of what are sure to be many new ideas about treatment to arise from our growing understanding of the fundamental role of brain pH in fear. Already, even with those treatments still only on the horizon, people with panic disorder, like my patient, may find some comfort in the mounting evidence that what they experience is not just “in their head” -- it is in their acid-sensing ion channels.
Richard Maddock is a professor of psychiatry at the University of California, Davis who studies brain metabolism in psychiatric disorders, including panic disorder.
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43 Comments
Add CommentAs someone who's lived with panic disorder for 16 years, I find this pretty interesting. Exercising and diaphragmatic breathing work wonders, which makes sense because it reduces lactic acid and increases oxygen intake. HOWEVER... some of it is in your head. For example, my "thing" has always been fear of disease/cancer (saw it at an early age in relatives), the panic attacks feed into this. I don't get them often anymore, as I've learned to control them, but feeling "ill" will bring them out, as did watching my aunt die of cancer last year. It feels as if the association pathway makes the attack happen. So my question would then be, if it's a simple lactic acid buildup or carbon dioxide spike, how does it "know" to happen right after I am feeling ill or nervous about some symptom I'm having? Or does the buildup cause me to feel ill and panic, so that I accidentally think that one causes the other? I don't know - I think you're onto something, but don't discount it being in the head, too.
Reply | Report Abuse | Link to thisThis would also suggest that breathing into a paper bag during a panic attack might only serve to make it worse. Hollywood script writers beware ;-)
Reply | Report Abuse | Link to thisQuestion: So my question would then be, if it's a simple lactic acid buildup or carbon dioxide spike, how does it "know" to happen right after I am feeling ill or nervous about some symptom I'm having?
Reply | Report Abuse | Link to thisAnswer: I'd say it has to do with the fight or flight response. IF one is presented with a 'situation' the body becomes more acidic and this allows for iron to be released from its' storage sites. NOW what does that mean .. ?
@xeno, I believe the idea of breathing into a bag is to prevent fainting and other symptoms caused by too little CO2 in the blood as a result of hyperventilating. It is not to treat the panic attack.
Reply | Report Abuse | Link to thisMy 19 year old son is just recovering from a 2 year bout with anxiety (it runs in our family - I had it too around his age). And...believe it or not the doctor told him to breath into a paper bag. Of course, this is the same person whose eyes would glaze over whenever we tried to get help. I do believe that focusing on your health is a general sympton of Anxiety. I know both my son, myself and my grandmother all did. Luckily I can say I've been fully recovered for at least 40 years,and my son is almost there. However I think the recovery factor also runs in families. I wish luck to the first person who responded here. I can seriously say Anxiety is by far the most frightening thing I've experienced in my life...partly because you know it's your own mind doing it to you.
Reply | Report Abuse | Link to thisI have a simply suggestion to scientists, who have been focused on regarding anxieties as a mental phenomenon forever. And to people with these problems. In my case I discovered, eventually, that these attacks were mild asthma-attacks of an allergic nature, and I suspect that it is so in many other cases. I am allergic to grass, dust and probably more, and it is therefore not entirely seasonal. If you do not know what is attacking you, especially if you believe it to be mental, your attack will worsen. Knowing that some allergic reaction is behind alleviates itself, as the mental stress is reduced. You will not die, you just have to find some way to alleviate the allergic reaction. Please give me a Nobel prize for this. (I am serious. This discovery has changed my life.)
Reply | Report Abuse | Link to thisI have an added comment to my previous one. Since stress of any kind makes an allergic reaction worse – the system feeds back unto itself – the feeling that ones breast constricts immediately causes panic, which makes the breast constrict more, etc etc. Anti-histamines (nasal sprays, and others) do help. Especially – the root of the problem is physiological. You are not crazy.
Reply | Report Abuse | Link to thisI can't believe they would subject anyone to a gas mixture containing 35% CO2! Here are some highlights from a few MSDS
Reply | Report Abuse | Link to thisCarbon Dioxide is a powerful cerebral dilator. At concentrations between 2 and 10%, Carbon Dioxide can cause nausea, dizziness, headache, mental confusion, increased blood pressure and respiratory rate. Above 8% nausea and vomiting appear. Above 10%, suffocation and death can occur within minutes.
1 to 1.5% Slight effect on chemical metabolism after exposures of several hours.
3% The gas is weakly narcotic at this level, giving rise to deeper breathing, reduced hearing ability, coupled with headache, an increase in blood pressure and pulse rate.
4 - 5% Stimulation of the respiratory centre occurs resulting in deeper and more rapid breathing. Signs of intoxication will become evident after 30 minutes exposure.
5 - 10% Breathing becomes more laborious with headache and loss of judgment.
10 -100% When the carbon dioxide concentration increases above 10%, unconsciousness
will occur in under one minute and unless prompt action is taken, further exposure to high levels will eventually result in death
Is it any wonder they got the results they did? By the sounds of it, they're lucky people weren't seriously injured.
Andira - I have cat allergies and panic disorder. There is a HUGE difference. It might be the culprit in a small percentage of cases, but it probably doesn't apply to as many people as you think. And, some folks might be triggered into a panic attack by the "buzz" from nasal sprays or allergy meds that cause the heart rate to speed up a bit.
Reply | Report Abuse | Link to thisFor me, positive and "in the now" (as opposed to what if in the future) thinking, plus regular exercise keeps me from going down that mental road. Breath control and "fighting through" the attack itself, or repeated exposure, has helped me stop panic in it's tracks or subdued it so that I can stand there and look perfectly normal, wherever I am, during the blitz. Just remember - normal or not - you are not alone.
They've known acid can induce paranoia since the sixties. This can be widely confirmed.
Reply | Report Abuse | Link to thisHi!: if the increaseof CO2 amygdala levels can trigger panick attacks, we may think in the panic attack as a self-administered therapy for this, as hyperventilation reduces blood CO2 levels, it in fact can cause respiratory alkalosis. In this kind of complex CNS activities, when we are still far, far away from knowing a correlate between hardware- biology, and activity -thinking, feelings and so on, it would be good to remember that french Rene Descartes described nerve transmission as an swelling of nerve that runs across it; then it was regarded as an electric phenomenon, and now we are aware of neurotransmitters, but all these things can be regarded just as epiphenomena, the nature of nerve conduction is other, and its function a different one, that can be considered what Immanuel Kant called apriorisms in the inner sensibility. As the science of epigenetics is deepening its knowledge, it becomes harder and harder to completely split biologic and psychologic causes and traits of mental disorders. Salud +
Reply | Report Abuse | Link to thisThis is an important development in our understanding of anxiety and panic disorder in partticular. However the danger is of taking a uni-casual approach to this. In a biological system everything is influencing everything else - neurological, physiological, cognitive, behavioural, emotional are all intertwined.
Reply | Report Abuse | Link to thisHowever if we consider "predisposing factors" then this new information can help us design new treatments.
I consider that the two main factors are a developed hypersenstivity in the amygdala through recurrent rapid high arousal (aka panic) - and the development of automatic cognitive (thoughts/beliefs) and behavioural responses which maintain the issue. - e.g. "oh my heart is racing that's horrible... I can't stand it" and then avoiding situations which raise arousal (so avoidance of anxiety sensations).
The key treatment for panic attacks is usually some sort of exposure to the anxiety/panic sensations so they can be reappraised and coping techniques learned (avoidance is not a coping technique!)
Perhaps this "exposure" is similar in nature to the exposure to stress during exercise - i.e. in the safety of the therapeutic session the client is safely stressed by anxiety and nerve cells develop improved metabolism through that experience?
what does breathing into a paper bag have to do with panic disorder?
Reply | Report Abuse | Link to thisOr, is it something 'entirely' different you are warning 'hollywood film makers' to watch out far?
I tend to believe so.
I have a question for YOU! What is it exactly, that occurs within the 'brain', which makes it less physical than any other sort of 'reaction', allergic or otherwise?
Reply | Report Abuse | Link to thisWhat type of 'mental' allergies do 'suffer' from?
Perhaps you should try removing your brain from your skull and attempt to survive, without it, 'physically', and without the help of any machines.
I wonder how 'physical' all the 'mental' anxiety phenomena would seem to you at that point.
What part of the 'brain' is NOT physical? And where would you like the "Nobel Piece of Idiot Prize" to be presented to YOU?
(I am serious. It is your 'lack of discovery' and Intelligence and that of so many others, including the 'professionals', in the 'psychiatric' and 'psychological' field of study, who have kept MY life, and Millions of others, completely STAGNANT, due to the entire 'MENTAL' stigma.)
The thyroid and the pancreas also can overproduce or underproduce chemicals, causing illness to occur. The thyroid, in fact, can cause some symptoms, similar to those, often referred to by you and people like you, as 'mental' illness, symptoms. Yet, no stigmas are placed on them. No 'extra' charges on insurance payments for those particular 'organ' malfuntions are incurred. They are 'properly' referred to as 'physical' illnesses. Just as any other illness is.
Hopefully you are a female, and you will live long enough to experience the popular 'change', usually occurring between ages of 45-55 or so. Also 'chemical' changes. AND also very similar to what YOU and YOUR kind refer to as 'Mental'.
Yes, you deserve a prize all right. And I certainly would treasure the idea of being the individual to present you with it. Me and all the millions who must deal with what YOU and your Millions hang on our PHYSICAL lives, every time you 'think', and then dare to say you have 'discovered'.
Interesting how no one who has commented has actually experienced a 'true' panic attack.
Reply | Report Abuse | Link to thisThey all seem to be 'allergy' related and comments/theories on the article.
So really, no one who has commented, other than myself, knows or understands the nature or the entire life experience of living with 'Panic Disorder'. Or how it can quickly turn into other disorders such as 'Major Depressive Disorder', due to not knowing WTF is going on, because it ISN'T allergies, that is for sure. And, it happens when nothing at all is going on that is 'scary' or threatening in any way.
One could be, say, viewing a really funny movie, in a theater, just as done all one's life, even 2 weeks ago, at the very same theater, and in the very same seat even, and BAM!
Oh, NO, those darn Allergies! They just are not setting in again. Uh oh, must be something else. But what? Hmmm? Well, we have no idea because, well, this has never happened before in our entire life.
I must be dying right here and now. I am afraid all those nose sprays are not going to work this time, and neither are all the 'Nobel' discoveries.
Wait, I think, I think, okay, yes, I can get a deeper breath now, after approx. 3-7 minutes, and my heart seems to be slowing down. Yes, my chest doesn't seem so tight, and my vision is coming back again. What? Oh, yes, I should get off my knees. I guess I do look very silly, don't I?
What? Psychiatric hospital?
Uh oh, I think it is starting to come back again......
LOL!!!
Go comment on an article more suited for your knowledge and experiences.
I have suffered panic attacks and anxiety for over 12 years now, i dont know what changed what happened , it just did. All i know is it has ruined my life, going from a person who could work full time had lots of hobbies so plenty of excersise, leaving me now almost housebound and not able to work. I had the disorder before i reached the, as someone suggested menopause, and for me it did get worse. I have believed the answer has been in the Amygdyla (sp) for sometime now, i have no scientific training. I am aware current medications will help but do not solve, all very hit and miss due to each of us being pharmacalogically different, and nothing is targeted. The learned avoidance behaviour, i have been working on, the exposure, over and over, and its got a little easier, but there are times i can not leave the house, even though i know i can do it,have done it, when you are actually in a panic nothing helps, and yes breathing into paper bag is a tool handed out by many medical proffesionals to help the hypervetilating caused when in panic, and does work sometimes. But as with most things if used over and over they lose there effectiveness. All i can really say on behalf of those who do suffer from this disorder, some of us short term some of us longer term, and are completely dibilitated from it. "unless you have truely had one you dont understand the mental and physical distress" thats the sooner we have a bespoke medication to help instead of being the given all sorts of other meds designed for other recognised mental illness, the better i will like it and hope for a improved quality of life.
Reply | Report Abuse | Link to thisThere is a mint to be made for the pharmaceautical industry
if they could come up with something that is actually developed specific, exclusively in the treatment of this disorder, I am not in a minority there are many millions of people worldwide who suffer, many in silence as they do not know what is happening to them. I had never heard of Anxiety Panic disorder when i had my first attack and took me 2 years to get any sort of help. Imagine waking already in full blown panic and dealing with that day in day out, its shattering both mentally and physically, and thats before the day starts. So where does that trigger come from sleeping itself, should i now avoid sleeping,? is that a allergic reaction to sleep? no. Also try living with a mind that is in a constant i mean non stop cycle of fear and worry,what if this what ifs....its no fun i can assure you.
I am never surprised when someone with cancer or cystic fibrosis or fibromyalgia ALWAYS says "I have the disease and you don't so I am an expert and YOU aren't" ..
Reply | Report Abuse | Link to thisIF you WERE so much of an expert .. we wouldn't be discussing this .. because .. ? .. you would have cured it .. wouldn't ya have .. IF you had ANY kind of ability ..
SINCE you STILL have it .. I'll assume you are just .. stupid .. isn't that how it works .. ?
Yep ..
Europeans have known about "acid-base homeostasis" and the negative effects of over consumption of our modern acid-rich fast-food and prepared-food diet.
Reply | Report Abuse | Link to thisWe know that cancer loves an acidic environment, and can't survive in an alkaline environment. We also know that our M.D.'s, our so-called "Doctors" don't know how to do anything about it.
I'm also surprised this article didn't look into the obvious ways that our acid-rich diet must be affecting anxiety, panic and PTSD.
The ASIC protein is, I think, the same one found in sour-detecting taste buds. It's also in the spinal fluid where it's involved with precise pH regulation of cerebral spinal fluid. So are there additional brain malfunctions when the overall brain pH is incorrect even if amygdala pH regulation is OK?
Reply | Report Abuse | Link to thisHi LH22,to help explain your panic reaction I would like to offer this insight.At age 5 your amygdala became primed to trigger anxiety in response to health issues which then continued thereafter.This caused your brain to pattern match in any situation which even vaguely resembled that early experience and this occurs at an unconscious level.Causing the bio chemical changes which follow this reaction(change in PH)What this research identifies is the usefulness of excercise and I would also suggest breath focused relaxation/meditation techniques as a means of personal control over panic attacks.
Reply | Report Abuse | Link to thisI suffered from Panic and Anxiety disorder for several years. It eventually developed into Agoraphobia as well. I am certain of this, for me, the panic cycle was thought driven.
Reply | Report Abuse | Link to thisFearful Thought (that pain I just felt in my chest is a heart attack) > Adrenaline Release (fight or flight) > Increased Respiration (slight hyper-ventilation) > Tightness of Chest, Dizzy, Light Headed, Etc. > Even More Fearful Thoughts.......and the cycle would spiral into a full-blown panic attack in seconds.
If this sounds like you, the cure is learning to replace your Fear based thoughts with thoughts based in reality... eg. there is a pain in my chest but it's most likely indigestion, etc. Once you stop the fearful thoughts the panic never happens.
I learned this from Attacking Anxiety and Depression by Lucinda Bassett. Changed my life after trying anti-anxiety meds, counseling, and group therapy ...all were ineffective for me.
@Egad:Yes, acid-raising diets are of our own making! I have done my own nutrition research on an evolutionary basis- the evidence that we are "chimps de luxe" by body design is overwhelming. Let's feed our inner chimp then, with plenty of RAW fruits and vegetables before anything else, and we'll be alright. The simple fact is that ALL man- or machine- made food, especially concentrates and condensates rendered denatured by cooking, make our leucocytes , and apparently also brain receptors,react in alarm, causing an automatic ph acid reaction. For a simple and natural species-specific nutrition concept, which is based on colour-pigment coding, please visit my website: Youthevity.com
Reply | Report Abuse | Link to thisI've been dealing with panic disorder for 5 years and went through all kinds of treatments you can imagine. Some of them made me feel better for sometime, but none of them, in fact, solved the problem. There is no case of panic/anxiety in my family. I also use the paper bag during the attacks, but it relieves only the synthom, not the disorder at all.
Reply | Report Abuse | Link to thisReferences please Neptunerover.
Reply | Report Abuse | Link to this@timg: I think they are referring to a 35% external mixture, not a 35% blood CO2 concentration.
Reply | Report Abuse | Link to thisWe have known for decades that when people with Panic Disorder start breathing to fast and too deep the they get too much O2 for the amount of CO2. If one teaches the afflicted person to NOT let their chest rise as they breathe in and DO stick their stomach out with each inhaling of the breath, that the anxiety subsides. I am a Psychotherapist and I teach that regularly. In the past some thought breathing into a paper bag would fix the anxiety, and it did for some: and our exhaled air is richer in CO2 that that air we breathe in. I am not sure why this research is considered so revealing.
Reply | Report Abuse | Link to thisWe have known for decades that when people with Panic Disorder start breathing to fast and too deep the they get too much O2 for the amount of CO2. If one teaches the afflicted person to NOT let their chest rise as they breathe in and DO stick their stomach out with each inhaling of the breath, that the anxiety subsides. I am a Psychotherapist and I teach that regularly. In the past some thought breathing into a paper bag would fix the anxiety, and it did for some: and our exhaled air is richer in CO2 that that air we breathe in. I am not sure why this research is considered so revealing.
Reply | Report Abuse | Link to thisPerhaps the excess of lactic acid in the brain is the result of a very active brain whose activity level is outstripping the body's capacity to process the acid, much like when a runner experiences muscle cramps when the body's functioning becomes anaerobic. (Of course, as a "victim" of this disorder, it is mainly a flattering hypothesis to lessen the blow!) What if a person with a panic disorder actually utilizes more regions of the brain when performing everyday tasks, thus leading to this excess and over-stimulation of the amygdala? My heart goes out to all of the others with this dreadful health issue.
Reply | Report Abuse | Link to thisNever mind about Hollywood script writers, its commonly encouraged in hospitals!
Reply | Report Abuse | Link to thisMany people for years have suggested 2-3 tablespoons of unfiltered vinegar per day to shift the body's ph toward alkaline. No pharma money in that. But I'd try it. 3 tablespoons and 3 miles--nirvana!
Reply | Report Abuse | Link to thisWhat about the old "first aid" for anxietyattacks, breathing into a paper bag? Wouldn't that increase the concentration of inhaled CO2?
Reply | Report Abuse | Link to this12yearson, i had the same kind of attacks you have experienced. I found that I had Mitro-valve disorder and subsequently discovered that supplementing with Magnesium and Vitamin D helped to gain control over those attacks. Don't know if it will work for you but thought I'd pass it on.
Reply | Report Abuse | Link to thisAs a female who reached menopause in the last year and never had a "panic attack" previously, I have come to believe that there are very definite chemical reactions involved. I tried dealing with sleeping problems last summer by taking a dose of 5-htp and was sent over the edge. I now find if I don't take alfalfa or red clover I feel anxiety creeping in, heart palpitations and vivid dreams. I have also wondered how a change in the way my body now uses glucose might be involved in this distressing change.
Reply | Report Abuse | Link to thisI wonder whether the assimilation of panic attacks to fear which occurs throughout the article is actually correct. There is a literature reported in Panksepp's Affective Neuroscience (OUP 1998) which holds that the neural circuitry of fear is distinct from that for separation distress, and that it is the latter which is primary in panic attacks. I would be grateful if the author could comment on this question.
Reply | Report Abuse | Link to thisThey way that they describe the amygdala as turning on or becoming more active as the ph drops is very consistent with the way I feel when I panic.
Reply | Report Abuse | Link to thisI could be walking through a store not feeling very well, kinda tired and weak, and without warning begin to feel as if I'm not getting enough air. It's as if the oxygen has been sucked out of the building, or my lungs no longer have the capacity to take the oxygen in.
Over time, I learned that when this happened, I would slowly start to hyperventilate after inexplicably feeling like I wasn't getting enough air. This would happen 100% independently of any external cause and start out unconsciously, so by the time I was aware I was hyperventilating, my hands would already be tingling and my mind would be racing trying to find the external threat or cause of my fear.
What I can do now is recognize that I'm starting to breathe too deep or fast and resist the almost overpowering urge to keep taking deep breaths or yawn. And like I said, this comes on unconsciously. I don't just hyperventilate for the fun of it. This could happen in the most comfortable place in the world, while I was thinking about the most happy times of my life, or thinking about nothing at all. It simply didn't matter. It wasn't brought on by separation, or any other trigger until later after experiencing panic attacks in so many situations. Then you begin to fear the panic attack and it's a whole new monster.
But if breathing co2 lowers ph in the brain and thus triggers over-activity in the fear centers of the brain, it also makes sense to me that the feelings that arise most prominently are a fearful feeling of not getting enough air and a strong desire to escape the room, building, car or whatever location you're in. Those are by far the 2 most prominent components of the panic attacks I've dealt with.
This is not true as hyperventilating actually rids the body of Carbon Dioxide and, among other things, causes the kidneys to release bicarbonate which increases pH (ie lowers H+ concentration). The observed effects happen when breathing too much carbon dioxide, which increases H+ and lowers pH, ie makes the brain acidotic. Thus hyperventilating might still prevent acidosis and in turn, panic attacks, unless it is from any pH that is not baseline rather than just a lower pH, as the article suggests.
Reply | Report Abuse | Link to thisdhavens, not sure if your response is to my comment, but if so, my feeling was that this lowered pH in the brain would lead to hyperventilation, almost like a false suffocation alarm. And because there is no need to gasp for air, it only leads to over-breathing which brings it's own set of uncomfortable symptoms.
Reply | Report Abuse | Link to thisIt would be fascinating to me if hyperventilating could reverse a panic attack, but I think for most people, the physical symptoms would outweigh any benefits. At least that seems to be the case with me.
Reply | Report Abuse | Link to thisthank you for a wonderful post. I too used to suffer from panic attacks
and anxiety disorder. I used to be a healthy woman so I never thought it could happen to me, but one awful evening, it did, and if it happened to me, it can happen to any one, at any given moment. to handle and overcome panic attacks and anxiety disorder I used the revolutionary "panic away" system, and it really helped me allot, and made my life better. and today I no longer suffer from panic attacks and I have gained back the control over my life
Reply | Report Abuse | Link to thisthank you for a wonderful post. I too used to suffer from panic attacks
and anxiety disorder. I used to be a healthy woman so I never thought it could happen to me, but one awful evening, it did, and if it happened to me, it can happen to any one, at any given moment. to handle and overcome panic attacks and anxiety disorder I used the revolutionary "panic away" system, and it really helped me allot, and made my life better. and today I no longer suffer from panic attacks and I have gained back the control over my life
http://stop-your-panic-attacks-today.com/
Reply | Report Abuse | Link to thisthank you for a wonderful post. I too used to suffer from panic attacks
and anxiety disorder. I used to be a healthy woman so I never thought it could happen to me, but one awful evening, it did, and if it happened to me, it can happen to any one, at any given moment. to handle and overcome panic attacks and anxiety disorder I used the revolutionary "panic away" system, and it really helped me allot, and made my life better. and today I no longer suffer from panic attacks and I have gained back the control over my life
Reply | Report Abuse | Link to thisthank you for a wonderful post. I too used to suffer from panic attacks
and anxiety disorder. I used to be a healthy woman so I never thought it could happen to me, but one awful evening, it did, and if it happened to me, it can happen to any one, at any given moment. to handle and overcome panic attacks and anxiety disorder I used the revolutionary "panic away" system, and it really helped me allot, and made my life better. and today I no longer suffer from panic attacks and I have gained back the control over my life
Reply | Report Abuse | Link to thisthank you for a wonderful post. I too used to suffer from panic attacks
and anxiety disorder. I used to be a healthy woman so I never thought it could happen to me, but one awful evening, it did, and if it happened to me, it can happen to any one, at any given moment. to handle and overcome panic attacks and anxiety disorder I used the revolutionary "panic away" system, and it really helped me allot, and made my life better. and today I no longer suffer from panic attacks and I have gained back the control over my life
I was disappointed that this article did not mention hyperventilation even once, as it is known to be one of the reinforcing factors in the cycle that can lead to a panic attack -- I just had my first, and it was because I thought I wasn't getting enough oxygen.. Anyway, obviously fear can be induced by the increased pH resulting from not enough CO2, so it would have been helpful to talk about the fear induced by decreased pH within this context. As it is, now I am just confused. Thanks a lot SA :P
Reply | Report Abuse | Link to this