View Full Version : The "reversion under stress" question...
2nd Jan 2011, 21:39
IATA's "MPL FAQ (http://www.iata.org/whatwedo/aircraft_operations/Documents/MPL%20FAQ_v1%204_2010%2002%2024.pdf)" makes the following supposition (para. 28.b):
If it is agreed that, at high levels of stress, humans revert to the basics first learned for a specific task, then it stands to reason that basic training on SEP aeroplanes for the MPL is, beyond a certain level, counterproductive, if not unsafe.
While it may well be received opinion (though note IATA's tentative "If..."), is there in fact any convincing psychological theory to underpin this concept of reversion under stress? One supported by meaningful, peer-reviewed studies in respected scholarly literature, that is.
How far do these supposed reversions go back... to the previous type flown? To the C152 back at the club? To the bike one had as a kid? Do no proven training methodologies exist to negate them - to 'wipe the slate clean', as it were?
Where does this notion, for instance, leave the 1000s-of-hours experienced pilot of, say, the F16, with its totally different handling qualities? Completely unsuitable ever to become an airline pilot, it would seem, lest s/he 'revert' under stress.
The idea that any other "lesser" experience puts subsequent large-aircraft piloting skills at risk has gained a lot of traction in recent years. But which is it - genuine basis for concern, or just part of the apologia for MPL?
2nd Jan 2011, 22:29
It was my understanding that reversion under stress had much to do with your MBTI personality type, the switch for an extrovert type under extreme stress would for example becomke introverted.
- What's the BUZZ? - In the Grip- Stress and theMBTI (http://www.assessmentbuzz.com/buzz/2008/2/20/in-the-grip-stress-and-the-mbti.html)
2nd Jan 2011, 22:50
You are referring to the concept of "Primacy". This is a very well accepted and well documented aspect of how people learn and how it affects subsequent behaviour. I am not a believer in citing "Wikipedia" but its a good source of references and for the purposes of this forum gives quite a nice explanation of "Primacy".
“...Primacy, the state of being first, often creates a strong, almost unshakable, impression. Things learned first create a strong impression in the mind that is difficult to erase. For the instructor, this means that what is taught must be right the first time. For the student, it means that learning must be right. “Unteaching” wrong first impressions is harder than teaching them right the first time. If, for example, a student learns a faulty technique, the instructor will have a difficult task correcting bad habits and “reteaching” correct ones.
The student's first experience should be positive, functional, and lay the foundation for all that is to follow. What the student learns must be procedurally correct and applied the very first time. The instructor must present subject matter in a logical order, step by step, making sure the students have already learned the preceding step. If the task is learned in isolation, is not initially applied to the overall performance, or if it must be relearned, the process can be confusing and time consuming. Preparing and following a lesson plan facilitates delivery of the subject matter correctly the first time...”
Retrieved 3 Jan 2011 from Wikipedia: Principles of learning - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Principles_of_learning)
Most of the early work was done on animals (as it always is) - you may remember Pavlov's dogs that demonstrated the "conditioned response". A Google search on Thorndyke will reveal a lot. There have been a bucket load of "human" experiments and follow up work with pilots (as well as other professions) and the concept of primacy or "reverting to type" is often cited in accident reports as causal.
Your queries regarding whether primary learning can be "undone" is less clear in the literature but the basic answer is probably "yes" with some caveats.
New neural pathways can be created in response to a stimulus that now requires a different response, however the old ones can't be destroyed (or at least we don't think so). A good example is to look at the training of an experienced light aircraft pilot onto a swept wing jet. For several lessons, they find themselves unable to stop using the rudder in an attempt to balance turns. Every time they roll with aileron, on comes the rudder. Eventually, usually after a few simulator rides, they have learned to stop using the rudder. However, come the check ride / 1179 / type rating test, there goes the rudder once again! I have had the pleasure of conducting many such conversions and have observed this phenomena many, many times. I have also converted many experienced airline pilots back to light aircraft and it rarely takes more than 10 minutes for them to get back into finessing the rudder as they used to so competently many years before -so those neural pathways were not destroyed, they have just been sitting dormant.
However, this ability to "switch" behaviours based on situation does require some spare cognitive capacity, which is something that we tend to loose under stress. Under extremely stressful situations we are more likely to revert to the most basic of behaviours - i.e. those that were learned first or revert to even more basic behaviours that were not learned but exist by instinct e.g. dissociative and inappropriate responses such as "freezing".
Try the International Journal of Aviation Psychology as a good start point for further information.
With respect to VinRouge's suggestion regarding MBTI, this is an interesting hypothesis but, to my knowledge, has no scientific backing. The MBTI is a useful tool to explore personality types but is not a scientific one. There are many interesting theories regarding MBTI linkages but, to my knowledge, there is little or no lierature on the area under discussion.
Hope this helps. Have a good 2011 everyone.
4th Jan 2011, 12:44
Propjet88 has elucidated both the theoretical and practical aspects of "primacy"/"reversion under stress". I have been witness to such a situation where a fast jet fighter pilot, with extensive experience on an older aircraft type, when faced with several emergencies (one after the other) in an advanced aircraft, failed to eject on landing, when aircraft's breaks failed (and unfortunately tail chute had burnt off and arrester barrier failed) despite the seat capability in this type...with tragic consequences. Though could not be proven, apparently, stress compromised the decision making as regards personal safety.
4th Jan 2011, 14:30
Fascinating topic, with posts so far from some very thoughtful and well educated contributors.
Please do keep the discussion going, I am very much looking forward to learning more about this concept.
4th Jan 2011, 15:57
I cannot vouch for the theory, but I have encountered what I believed to be reversion behaviour when investigating serious incidents.
In one, during a 'demanding’ landing on a short runway in an aircraft without reverse thrust, the pilot appeared to have reverted to a prior habit of pushing the control column fully forward when on the ground. This was a requirement of a previous type which had rear-engine reversers.
Unfortunately the forward column movement lifted the tail sufficiently to break the ‘on-ground’ switches which retracted the spoiler, exacerbating the landing difficulties, thus the forward control position was maintained.
This appears to be reversion to habit due ‘anticipated’ stress of a difficult task, i.e. the pilot pre aroused his behavioural state in which a reversion could happen; he created an opportunity for ‘tunnel vision’ behaviour.
Another incident involved a very experienced Captain who encountered a rare form of tail icing during the climb. This caused a harsh and very disturbing vibration, the frequency and severity such that it was painful and affected vision. The Captain described his appreciation of the overall situation as being life threatening – he was going to die.
The mental representation of the situation appeared to be that ‘vibration’ represented a stall condition, even though the crew were 'aware' (perhaps not conciously) that the climb speed was well above any stall speed. Thus the aircraft was accelerated, which increased the vibration and severity of the event; fortunately the situation was resolved when the aircraft exited the environmental conditions.
An interview with the Captain, whom I knew from previous military flying, suggested that he had lost all sense of reality of the situation – he was unable to think, thus his actions related to absolute basics (subconscious) – survival.
In this sense, perhaps the vibration / stall relationship was a deeply embedded fact of ‘knowledge’ and was recalled subconsciously like a physical skill - but a skill of thinking – even an aspect of experience / expertise.
I note some similarity in this with the research of Orasanu and Martin (www.dcs.gla.ac.uk/~johnson/papers/seattle_hessd/judithlynne-p.pdf) where poor decisions can be broadly categorised as either not recognising the situation, or if understood, selecting an inappropriate course of action. Both the poor situation assessment and the selection of a course of action might represent limited mental resources due to stress. If so then these types of erroneous situations (reversion to habit) might be reduced by stress management / workload management training.
4th Jan 2011, 22:05
Many thanks for suggesting the move of the topic to this forum, agreed it is more appropriate.
And also thanks to you (and other contributors) for the excellent and stimulating replies to the query I have modestly put forward here.
Yes, I should have adverted to 'primacy' as that is at the centre of my interest. What I am gnawing at is the principle - at the heart of the MPL concept, for example - that, for fear of reversion under stress to incorrect intitially-learned skills, habits, attitudes, we must therefore train pilots, from almost the beginning, in large, fast, public transport style aircraft (real or simulated). Including, indeed, a specific type and associated rating as part of a pilot's ab initio training. Not to mention sponsoring carrier's SOPs.
We might characterise this approach as 'avoiding the wrong kind of experience', and indeed that idea is explicit in official documentation. Implicit in this approach is an acceptance of the notion, (which you advert to Propjet, though I guess you don't entirely agree with it), that 'retraining' is always going to be less meaningful, to offer less of a guarantee of correct operation and decision making, than 'original training'.
The retrained neural pathways, as it were, will be less profoundly marked out, they will become 'the road less travelled' than the orginal trained pathways, under stress.
If this supposition is correct (and it would be interesting to know, even for those who have problems with that fashionable mental model, if it has any neurobiological validity) the question still remains as to whether it is an immutable part of human make-up. Or could it possibly be because we have paid insufficient attention to retraining principles and methodologies?
That seems an worthwhile consideration to me because I am inclined to believe that most training is 'retraining' in important ways. Virtually any deep human learning involves abandoning raftloads of previously held suppositions. Not least, in aviation, learning those many non-handling-related decision-making skills which are fundamental to the maintenance of safety.
All I am doing here is holding up a little flag on behalf of 'retraining' to garner it some more attention, and perhaps a little more respect. I'm suggesting it's far more prevalent than we might imagine, even when we think we're doing 'original training'.
Thank you for the reference to that fascinating Orasanu and Martin paper, which teases out some very interesting and germane concepts. I've just skimmed it - now for some bedtime reading!
6th Jan 2011, 07:59
talking about Orasanu's paper, the aspect of Naturalistic Decision Making (NDM) (by Gary Klein en.wikipedia.org/wiki/Gary_A._Klein and ARA :: Locations :: Klein Associates Division, Fairborn, OH (http://www.decisionmaking.com)), as referred in the paper, is fascinating in terms of making people learn the decision making in real life scenarios. And it may be the next step forward in aviation setting beyond CRM and LOFT.
However, correct me if I am wrong, NDM has not yet been embraced in aviation whereas it has proven its worth for fire fighters and other emergency workers.
May be time is ripe now:)
6th Jan 2011, 20:18
To clarify an earlier point, my reference to stress / workload management assumes control of surprise and even fearful aspects of encountering situations which might not be believed to be possible, e.g. a pilot who experienced a thrown tyre tread at rotate, experienced cockpit vibration / motion which he could not envisage as being possible or safe for the aircraft; the subsequent actions (land ahead) may have represent the basic fight or flee reaction. These situations involve aspects of knowledge and belief, these also connect with experience - hard facts and projections of existing knowledge, e.g. what conditions an aircraft has been certificated to withstand and continue flight safely.
Avoiding the wrong kind of experience is not always possible. An example (now probably dated by newer training aircraft) where during twin engine training there was significant focus on quickly feathering the prop to maintain control, but in most modern turboprops, hasty action may not be warranted, if required at all where auto feather systems are fitted. Similar training aspects are covered in the PSM+ICR report.
However, this type of experience can be modified by good instruction which would put the need for haste into context – “in this aircraft … because …. but in other aircraft it may not be necessary”. This requires both good instructional technique and a depth of knowledge of the industry; the latter may not be available if ‘junior’ / inexperienced instructors are used.
In this form of instruction the subject is on a broad knowledge base which subsequently can be developed in different areas as the aircraft type changes. Whereas a narrow knowledge base (type-specific training) would need ‘unlearning’ in order to get back to a broad knowledge base or yet another type-specific narrow knowledge base.
Any tendency to revert to ‘first learnt best remembered’ might be tempered by the broader knowledge base; hence teach principles not only the specifics.
PSM+ICR report. (www.faa.gov/aircraft/air_cert/design_approvals/engine_prop/media/engine_psm_icr.pdf)
7th Jan 2011, 01:34
AvMed.IN, re NDM, this involves ‘experience’ and thus I agree is relevant to the thread.
NDM uses situation assessment as a baseline; good awareness helps quell surprise / stress; it provides external knowledge or can trigger memory-knowledge to solve the problems in the situation – using experience – learnt from real life scenarios.
My understanding is that NDM indicates how humans make decision in certain circumstances. Thus all of us (including aviation), could behave this way, but as yet it is not fully explainable and thus not able to be taught, only compared – see refs below, ‘experts vs novices’. Fire-fighters were used in the initial research.
Some areas of aviation have recognised NDM, but this has been held back by the number of competing academic views (see below) and particularly the FAA’s promotion of DECIDE or similar process-based acronyms.
As I understand, decision making theories are in two broad categories. First, the normal ‘conventional’ approach, which I liken to problem solving and can be undertaken in the fullness of time with a range of data enabling option evaluation. This is strategic decision making – planning, e.g. preflight, or a prelanding briefing where many what ifs can be considered.
“A briefing is the flight plan for the mind”, and thus if aspects of surprise or stress have already been considered in a plan, this might reduce any reversion tendency.
Second, NDM is used in time critical situations often characterised by poor situation cues; this is where experience is relied on. This could be considered tactical decision making, including verification or modification of existing plans – N.B. the need to have a plan, and the need to be aware of the situation – mental models.
In this sense, reversion might be a chosen option within the decision. It would be interesting to know if there is a difference between experts and novices in reversion tendencies in these circumstances – I suspect that experts are less prone, thus expertise could offer a defence.
The refs below provide a good overview of the theories - tough academic reading at times. There are some (significant IMHO) indications as to how experience might be gained / accessed. In particular, some hints as to how some aspects of experience might be taught - knowledge gained, without being in real life scenarios.
Also, the importance of situation assessment / awareness is of note; this should receive more attention during training. I find these aspects of great interest in the commercial pressured, minimal training cultures of modern aviation.
Taking stock of naturalistic decision making. (http://khup.com/download/0_keyword-taking-stock-of-naturalistic-decision-making/taking-stock-of-naturalistic-decision-making.pdf)
Expert Decision-Making in Naturalistic Environments. (http://dspace.dsto.defence.gov.au/dspace/bitstream/1947/3687/1/DSTO-GD-0429.pdf)
A review of time critical decision making models. (www.cs.unc.edu/~azuma/aerospace06_final.pdf)
Thinking Ahead: Using Strategic Behavior to Avoid Errors on the Commercial Flight Deck. (www.dcs.gla.ac.uk/~johnson/papers/seattle_hessd/WR_strat-p.pdf)
7th Jan 2011, 02:26
I must say that it is pleasant to see a thread where relevant issues are discussed constructively and politely. This is indeed rare in discussions associated with MPL where emotion and passion (for and against) are rampant!
Just to develop the discussion a little, from the thread to date, primacy (in relation to pilot training at least) can perhaps be considered simplistically under two broad areas - manipulative skills and decision making.
The IATA statement regarding excessive training on single engine aircraft being counterproductive is perhaps more associated with handling skills but it is worth considering that not only are light aircraft handing skills being embedded but so too are aeronautical decision making skills and the thread is now moving this way.
I’d suggest that aeronautical decision making is really all about risk management and in risk management context is all important. Perhaps then the issue for early training is not one of single engine aircraft per se, but at least equally importantly one of single pilot decision making.
AvMed.In brought up NDM as relevant and Alf has expanded on that. NDM is about decision making “in context”. Zsambok defines NDM as:
“...how experienced people, working as individuals or groups in dynamic, uncertain, and often fast paced environments, identify and assess their situation, make decisions and take actions whose consequences are meaningful to them and to the larger organisation in which they operate.
Elliott sums this up as
“...how people use experience to make decisions under time pressure, with unclear or changing conditions, degraded information and within team interactions...”
So, perhaps learning to make decisions solo is not the best way to learn to make decisions in a team environment?
The various references that Alf cites discuss the issues in depth but for the sake of this thread, here is a simplified decision making process proposed by Kepner and Tregoe which is intuitively attractive and goes along the following lines:
Analyse the Problem
• Problems are deviations from agreed / defined performance standards
• Problem must be accurately identified
• Problems are recognised by some change from a distinctive feature
• Causes to problems can be deduced from relevant changes found in analyzing the problem
• The most likely cause to a problem is the one that exactly explains all the facts
• Objectives must first be established
• Objectives must be classified and placed in order of importance
• Alternative strategies / options must be developed
• The options must be evaluated against all the objectives
• The option that is best able to achieve all the objectives is the tentative decision
• The tentative decision is evaluated for more possible consequences ?
• The decision is enacted together with any additional actions necessary to prevent any adverse consequences.
Kepner, C.,H., & Tregoe, B.,B., (1965). The Rational Manager: A Systematic Approach to Problem Solving and Decision-Making. McGraw-Hill, New York.
I find this model quite useful to stimulate discussion in CRM training as it is the understanding of this basic process that underpins the various decision making models such as “CLEAR”, “GRADE”, “DECIDE” etc that are often taught as “rote methods” for decision making. As Alf says, teaching the underlying principles, as opposed to just the specifics, is important.
However, this process and the “rote” models that fall from it do not consider many of the variables mentioned previously under NDM. Just taking the example of time, if time is limited, which bit(s) of the rote process, if any, could or should be skipped or abbreviated? It may be also worth considering the effect of the “fear factor” as a variable which may or may not influence quality of this process when the ultimate “adverse consequence” of a poor decision may be a disaster.
Those of us who have experience of operating in the multi – crew world will inevitably have come across the decision making “one man band” i.e. the pilot who seems to be unable to operate within the synergistic benefits of a crew. I wonder if this may reflect that they have become a little too “expert” in single – pilot decision making due to patterns formed by previous experience?
There was some research done earlier this century on the possible negative results of 'imposing' a structured decision (eg 'Dodar') making formula on the natural process.
Before DODAR etc was invented (Shirley invented it I think for BA) I believe we all progressed with an abnormal situation in a 'natural process' that included all elements of DODAR etc.
In such situations (and even in normal ops of course) we have made decisions etc and then reviewed them quietly in obvious addition to discussion with the chap/ess in the RH seat who has saved my bacon on more than one occasion - flying aircraft is a constant process of reviewing decisions in real time all the time.
I'll be honest and state that in the sim I always verbally go through a dodar to ensure that the TRE takes note - which he/she always does. In real life I've always carried out a 'natural process' that ensures we catch most of the errors - we were selected for this job presumably because, amongst other skills, the airline felt that we would be able to make correct decisions (constantly reviewed) under difficult circumstances.
Hope you are well BOAC. I'm just about to start a 50% contract in West Africa - I'm starting to slow down a bit!
8th Jan 2011, 06:48
thank you for your lucid explanation on NDM and the valuable references.
Despite its limitations and lack of acceptance in aviation thus far, I feel compelled to apply Gary Klein's propagated recognition primed decision making (RPD) as a tool for spatial disorientation countermeasure (particularly for the benefit of combat pilots in single cockpit). I need time and patience to prove my hypothesis, since that is one area close to my heart (and aviation safety), but very difficult to substantiate (considering many confounders in aviation).
you have wonderfully summarised the discussion thus far. While you discussed about single pilot in a different context, I cannot resist bringing in the need for CRM for the combat pilots. Failure of a combat pilot to see himself as a member of the the formation he is flying in, results in precious loss of lives, due to (sometimes preventable) errors/mistakes. Have been advocating CRM for single cockpit ( Reality Check – CRM in Single Cockpit | Aviation Medicine :: Aerospace Medicine (http://www.avmed.in/2011/01/reality-check-crm-in-single-cockpit/)) for long, without success.
9th Jan 2011, 19:21
PJ88, you raise some interesting points, which I consider below as comments and questions for discussion:
You imply that primacy is skilled behaviour, but this might not be the case. A novice decision maker is unlikely to have naturalistic skills due to the lack of ‘experience’, thus reversion in decision making would be back to basic teaching, e.g. an unskilled problem solving approach. If so then the novice is poorly equipped to deal with time critical, cue limited situations as appears to be the case.
Thus the training problem is to develop decision making expertise early in a career; perhaps vitally important in modern times with foreshortened career progression.
No doubt there are many ways of looking at decision processes; risk management could be a practical area which can be explained. Risk like many other aspects depends on knowledge, and how and when to employ that knowledge – how close to the edge of ‘safety’ – context dependent.
If you train the decision process (your example), it tends to be problem solving – strategic decision making; it lacks the dynamic element of tactical situations, thus more suited to planning.
IMHO the current safety issues relate to tactical decisions which contextually are linked to NDM / RPD. Thus situation assessment and expertise are key issues.
Questions: How is NDM achieved, how should pilots assess situations, what is expertise and how is it gained, can it be taught without exposure to reality?
Attempting to understand some of these aspects I considered my own, (dated) training experiences – (military, single seat). This was based on an extensive knowledge base and a broad range of practical experience. Both aspects focused on operating the aircraft – context training, not just handling skills.
Another significant contribution appears to have been ‘hidden’ in airmanship. This developed abilities to generate new knowledge from existing knowledge and previous experience, how to use what had been learnt in one context in another, without actually being there. This appears to be training in “how to think”; a significant item. The aspects above also continuously improved the base line of skill/experience; thus, the reversionary skill level was above ab inito and always improving.
There will be differences between military and civilian training, but the principles should be similar.
Re “… perhaps learning to make decisions solo is not the best way to learn to make decisions in a team environment? … too “expert” in single – pilot decision making … ”
This I would question, even turn around. It is entirely wrong to expect team DM to be like a committee. Solo DM training must instil personal responsibility for the decision (ownership / leadership).
IMHO the socialised CRM thinking, or fear of the ‘one-man band’, in training, is a cause of many operational problems.
Team decisions require good DM leadership (this starts with solo DM – the individual, the leader) and then together with independent monitoring-enquiry, again a solo activity from other team members, this opens discussion within the team as necessary. The group aspect comes from having a shared mental model.
We must beware of the hazards of using strategic decision making, a slow methodical behaviour, if the situation is one requiring quick tactical decisions, NDM; i.e. as in Orasanu & Martin – failing to understand the situation or not choosing an appropriate action (mode of thinking/decision making).
CRM behaviour (not DM) requires an appropriate cockpit gradient. Crews are more likely to consist of an experienced commander with a relative novice as monitor; each will be able to contribute to DM as above, but not equally.
Tactical decisions are not team decisions - RTOs, EGPWS, Windshear, TCAS, stall, go around, flight system mode change, autopilot disconnect, etc – many of which are central to recent safety issues.
Questions: How do experts make decisions in these areas? Are the key areas for training associated with erroneous behaviours in tactical decision making, human factors?
Is the difference between an expert and a novice decision maker the ability to assess the situation and choose an appropriate mode of thinking (type of DM)? If so, this is where training must focus its efforts.
9th Jan 2011, 19:47
AvMed.IN, ‘RPD as a disorientation countermeasure’ sounds a very interesting concept.
Perhaps the contributions of situation assessment and knowledge in RPD will provide a route towards an understanding of how these can reduce the prevalence of disorientation.
There was an interesting article in New Scientist 10 Nov 2010 “The rational case for irrational thinking” which discusses research, culture, etc depending on the view taken - WEIRD. "Western, Educated, Industrialised, Rich and Democratic".
A minor point related to cultural frames of reference, they can differ; this might relate to disorientation training, the conflict between body-sensed frame of reference / instrument displays and the natural frame of reference.
Is disorientation of form of reversion to a natural frame of reference?
As a thought about combat pilots and frames of reference, in a 1 v1 combat the norm may be to describe the adversary relative to your self, e.g. forward, to the right, and above.
In a multi-aircraft combat scenario, dependant on communications, the frame of reference changes to a fixed based reference (Nav fix) e.g. N,E,S,W, and relative altitude from the reference point.
There could be aspects of CRM here – an individual view vs a group view, the latter dependent on communication.
Also, there may be similarities with problems of cabin-crew to flight-deck communication in large aircraft. First, it is necessary to specify the frame of reference – upper deck, left rear door, facing forward. In some aircraft the doors/cabins are so similar the crew might not know where they are! (Label the doors).
What’s the first aspect of a mobile phone call – Hi, I’m here … location described …”
24th Jan 2011, 02:46
To answer the OP original question.
There is no scientific evidence to support the theory of primacy as applied to learning/training in general.
It's interesting that someone mentioned the MBTI because Jungian theory posits that only certain personality types are subject to primacy; namely, the sensing type.
On the other hand, Freudian theory states that primacy is primary an age-related issue and that under stress people will revert to childhood.
Personally, I think that primacy or reversion under stress is a lot of psychobabble. The claim that first impressions are inedible impressions has little scientific evidence to support it either in the field of education or psychology itself. To the extent that primacy has scientific support it's usually on the basis of efficiency, not effectiveness. That has little to do with pilot training.
25th Jan 2011, 00:51
Everyone responds differently under duress. Some step up, some freeze.
The argument is effectively moot if you hire people that neither have the proven experience in dealing with emergencies, in an airplane or not...your simply gambling that the first time it comes up, with you in the back, that they will step up should that event come to bear.
My personal experience is that some people look to challenge themselves under stress, others avoid those situations. Those that challenge themselves are the ones better 'trained' to deal with these events mentally.
As far as how far or how willing a person reverts to 'crawling into a corner in the fetal position' can simply be tested by putting them in situations where they are tested for that. Some will fight to the end, some will not.