ventromedial prefrontal cortex

facts about PTSD

PTSD (post traumatic stress disorder) is NOT a mental illness. - it is a psychological injury. 

how does your brain change with ptsd ? 

hippocampus shrinks 

this area helps us distinguish past and present memories. 

increased activity in the amygdala   

helps us process emotions and is also linked to fear responses. 

ventromedial prefrontal cortex shrinks

this region regulates negative emotions that occur when confrontation with specific stimuli. 

these changes in the brain chemistry are the reasons why only treatments such as EMDR and CBT can fully reverse the effects of PTSD . 

(information to follow about these therapies.)

anonymous asked:

Since you kindly mentioned that you were willing to discuss having PTSD, what are a) some factors you'd like writers to keep in mind writing a character with PTSD in a medieval fantasy setting and b) some characteristics, etc. you'd want to see from such a character?

******* TRIGGER WARNING: Discussion on trauma, mentions of specific triggers such as violence and rape******

This is a complicated question. Not because it’s difficult to answer from my own perspective, but because I can’t speak for everyone with PTSD. It’s difficult to categorise how best to display it, because no one person’s mental illness is the same as the next person’s. 

I would recommend trawling some PTSD support forums/websites that might give you an insight into how people’s individual experience has affected them and how it manifests. Some people will experience a handful of the possible associated symptoms, whilst others will have a completely different handful. 

I think some of the more universal traits of someone experiencing this would be hyperarousal (being aware of everything, all the time), invasive memories (not necessarily flashbacks, I find the two are quite different) and avoidance of similar situations or triggers. These seem to be the more common aspects of how it presents, but again, not everyone will have them. Gathering multiple perspectives of how PTSD affects different people is as essential as any other research when you’re trying to avoid tokenism and stereotyping; no one person’s experience can become an umbrella to describe everyone’s. 

I’d say that in a medieval setting, you’d need to bear in mind that their perspective on PTSD would be very different depending on the culture and understanding of psychology. In our world, recognition of PTSD as a diagnosable and treatable mental illness didn’t truly begin until the twentieth century (though there are indications that it was understood well before that, both in literature and case studies), as ‘shell shock’ in World War I veterans. 

However, the real universal part of PTSD is the trigger. ‘Trauma’ is the important part to consider. It isn’t a mental illness that occurs because of innate biological factors, it is directly triggered by an event that is considered to be traumatic. A person may be predisposed to developing PTSD because of a history of trauma or anxiety, but there is a definite beginning to the journey it takes you on. Since we were able to process fear and turn it into trauma, we’ve experienced these events. Nearly being killed as a primitive human would have similar lasting effects to nearly being killed as a supposedly evolved human. It’s difficult to say how traumatic people in the ‘olden days’ would find things that we find to be traumatic now. Generally, we consider trauma to be ‘outside the usual human experience’. In the times when death and looking it in the face were more common, does this fall into the category of trauma?

That’s for your world-building to figure out. Deciding what is classed as a regular human experience, what one has learned to cope with, and what is unusual, is down to you. It’s important to bear in mind that some things, like genocide, rape, torture and war are considered to be traumatic events for the vast majority of the population.

There are three primary areas of the brain that are affected by PTSD:

1. The Hippocampus

This is the part of the brain that processes memory.  A lot of the time, the brain fails to put a typical time stamp on the memory of the traumatic event(s) because it’s too busy trying to protect you at the time of the incident. Ordinarily, when we remember something, we know roughly when it happened, because our brain properly processes the timestamp.  

This is very common in trauma, regardless of whether a person goes on to develop PTSD or not. This becomes problematic with PTSD in particular because the brain has not put this memory where it’s supposed to be; it could be happening right now, or have been one minute ago. This is the part where it becomes difficult to encounter triggers to the memory, because it’s difficult to determine when it actually happened, despite cognitively being aware that it’s in the past. 

This is the part of the brain responsible for intrusive memories, flashbacks, avoidance of triggers and being unable to properly distinguish between reality now and the memory then. 

2. The Amygdala

This is the place that is responsible for handling your emotions, including fear. It’s your processing core. Your fight or flight responses live here, and they’re reacting to what’s happening right now. Since it’s so difficult to tell what is happening now and what happened then, this area lights up like a Christmas tree when exposed to triggers or reminders. It doesn’t know that it isn’t happening now, because there is no timestamp. It reacts as though it is happening now, or did recently. The reaction to the trigger is often as strong as the reaction to the initial trauma, because it -is- the initial trauma, relived. 

3.  The Ventromedial Prefrontal Cortex (VPC)

This little badger is where you regulate the emotions generated in the amygdala. This is the part of your brain that tells you that plane turbulence is just a normal part of flying, and you really don’t need to worry about crashing right now. There is often a marked reduction in the activity of this part of the brain in people who have PTSD, causing the person to behave in ways that others may consider to be overreacting or excessive, when the trigger may have been tiny. 

So, between the above, you get this ‘circuit’ that leaves your amygdala completely confused. Your hippocampus is unable to process the trigger properly, so it tells the amygdala to panic. The VPC then sits on its arse and doesn’t tell the amygdala to calm down. How people behave when their fight or flight instinct is given a resounding kick depends on a whole multitude of factors. 

PTSD tends to follow a particular pattern, and for some people, they only experience symptoms for a few months before they simply go away. Others are saddled with it for years, and others carry it for the rest of their lives. It goes a little something like this:

Traumatic Event -> belief that I am about to die or come to serious harm -> brain protects itself by not processing the trauma right now, there is no time and I must survive -> end of the traumatic event -> brain begins to engage with the memories and trauma later, when it begins to feel that it is safe to do so, resulting in delayed reaction to the traumatic event. 

The definition of the traumatic event has varied throughout the history of our developing understanding. Initially, only life-threatening events were considered to be significant enough to cause PTSD. The definition has now been expanded to cover events that have significantly impacted an individual’s perception of their own safety, such as sexual assault and bodily harm. At present, other significant life stressors like divorce, financial collapse and personal failure would be considered adjustment disorders rather than a traumatic response disorder. 

Realistically, PTSD happens differently because we are different people and we experience even the same events in a different way. One event could have a thousand different stories depending on the people who observed/experienced said event. 

So, once you’ve done your reading (I really do recommend personal testimony over psychological science reading), consider your character and their position in the world. Would PTSD be considered to be ‘traumatic neurosis’ of a sort, where it’s considered to be a personal weakness rather than a psychological response? Or is there a broader understanding of what is going on for these people?

You need to look at things like how the three areas of the brain listed above would cause problems for your character. What are things that could trigger them? Bear in mind that this could be as minute a thing as a vaguely similar sound, sentence, object, facial feature or smell and that people with PTSD are often aware of every little thing going on around them (being stuck in a loop of your fight or flight reaction will do that to you). 

How do they behave when they’ve been triggered? This is where your reading of personal testimony comes in ridiculously handy, because frankly I’m sick of seeing the traditional war veteran with PTSD who goes on a shooting spree because he thinks he’s still in Afghanistan. We’re not deluded, we’re struggling with memory. 

How do other people react to this? Does it actually endear them to people (in earlier cultures, an enhanced fight response might make a person seem like a good choice for a leader)? Does the constant presence of fight or flight reaction actually prove useful in their surroundings? How much psychological pain does this cause them? Are they able to articulate this? What would the people around them think to what they said about their experiences? 

With regard to ‘characteristics’, there are no characteristics for people with PTSD. It’s all very individual, which seems to be a) half of the trouble in people recognising that they may have it, and b) the other half of the trouble in depicting PTSD accurately in the media. I’d really just like to see a character who’s like me; a regular person trying to come to terms with something awful, struggling with it and their own brain and handling it in their own unique way. 

I know a lot of this was more about the documented stuff about PTSD rather than my own experience, but frankly, I don’t feel qualified to speak about ‘the PTSD experience’ for everyone. I’m just me. I’ve experienced it my own way, dealt with it my own way, as my fellow trauma-bearers will their way. I’m happy to do another ask about my personal experience, but that’s exactly what it would be; my experience, in my brain, relatable to me, not everyone. 

I hope it helped at least a little. 


Will computers ever truly understand what we're saying?

From Apple’s Siri to Honda’s robot Asimo, machines seem to be getting better and better at communicating with humans.

But some neuroscientists caution that today’s computers will never truly understand what we’re saying because they do not take into account the context of a conversation the way people do.

Specifically, say University of California, Berkeley, postdoctoral fellow Arjen Stolk and his Dutch colleagues, machines don’t develop a shared understanding of the people, place and situation – often including a long social history – that is key to human communication. Without such common ground, a computer cannot help but be confused.

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Brain study shows why some people are more in tune with what they want

Wellcome Trust researchers have discovered how the brain assesses confidence in its decisions. The findings explain why some people have better insight into their choices than others.

Throughout life, we’re constantly evaluating our options and making decisions based on the information we have available. How confident we are in those decisions has clear consequences. For example, investment bankers have to be confident that they’re making the right choice when deciding where to put their clients’ money.

Researchers at the Wellcome Trust Centre for Neuroimaging at UCL led by Professor Ray Dolan have pinpointed the specific areas of the brain that interact to compute both the value of the choices we have in front of us and our confidence in those choices, giving us the ability to know what we want.

The team used functional magnetic resonance imaging (fMRI) to measure activity in the brains of twenty hungry volunteers while they made choices between food items that they would later eat. To determine the subjective value of the snack options, the participants were asked to indicate how much they would be willing to pay for each snack. Then after making their choice, they were asked to report how confident they were that they had made the right decision and selected the best snack.

It has previously been shown that a region at the front of the brain, the ventromedial prefrontal cortex, is important for working out the value of decision options. The new findings reveal that the level of activity in this area is also linked to the level of confidence participants placed on choosing the best option. The study also shows that the interaction between this area of the brain and an adjacent area reflects participants’ ability to access and report their level of confidence in their choices.

Dr Steve Fleming, a Sir Henry Wellcome Postdoctoral Fellow now based at New York University, explains: “We found that people’s confidence varied from decision to decision. While we knew where to look for signals of value computation, it was very interesting to also observe neural signals of confidence in the same brain region.”

Dr Benedetto De Martino, a Sir Henry Wellcome Postdoctoral Fellow at UCL, added: “Overall, we think our results provide an initial account both of how people make choices, and also their insight into the decision process.”