Forensic Biomatics

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Forensic science (often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to the legal system. This may be in relation to a crime or to a civil action. The use of the term "forensics" in place of "forensic science" could be considered incorrect; the term "forensic" is effectively a synonym for "legal" or "related to courts" (from Latin, it means "before the forum"). However, it is now so closely associated with the scientific field that many dictionaries include the meaning that equates the word "forensics" with "forensic science".

Connections to Biomatics may include:

 

  • Drug effects on behavior
    • Methyltransferases
    • Acetyltransferases
    • Inhibitors
  • Developmental effects
  • Decision Theory


       

    Contents

    Decision Theory

    Decision theory in mathematics and statistics is concerned with identifying the values, uncertainties and other issues relevant in a given decision and the resulting optimal decision. Most of decision theory is concerned with identifying the best decision to take, assuming an ideal decision maker who is fully informed, able to compute with perfect accuracy, and fully rational. The practical application of this prescriptive approach (how people should make decisions) is called decision analysis, and aimed at finding tools, methodologies and software to help people make better decisions. 

    Sameness

    In the common law tradition, case law interprets laws, via precedents, based on how prior cases have been decided. Case law governs the impact court decisions have on future cases. Unlike most civil law systems, common law systems follow the doctrine of stare decisis in which lower courts usually make decisions consistent with previous decisions of higher courts.



    One to One Correspondence

    The notion of one-to-one correspondence is  fundamental to counting. When we count out a set of cards, we say, 1, 2, 3, ... , 52, and as we say each number we lay down a card. Each number corresponds to a card. Technically, we can say that we have put the cards in the deck and the numbers from 1 to 52 in a one-to-one correspondence with each other.

    In abstract algebra, a homomorphism is a (one to one) structure-preserving map between two algebraic structures (such as groups, rings, or vector spaces). The word homomorphism comes from the Greek language: homos meaning "same" and morphe meaning "shape". Note the similar root word "homoios," meaning "similar," which is found in another mathematical concept, namely homeomorphisms.

    In abstract algebra, an isomorphism (Greek: ison "equal", and morphe "shape") is a (one to one and onto) bijective map f such that both f and its inverse f −1 are homomorphisms, i.e., structure-preserving mappings.


    Morphism

    In mathematics, a morphism is an abstraction derived from structure-preserving mappings between two mathematical structures.

    The study of morphisms and of the structures (called objects) over which they are defined, is central to category theory. Much of the terminology of morphisms, as well as the intuition underlying them, comes from concrete categories, where the objects are simply sets with some additional structure, and morphisms are functions preserving this structure. Nevertheless, morphisms are not necessarily functions, and objects over which morphisms are defined are not necessarily sets. Instead, a morphism is often thought of as an arrow linking an object called the domain to another object called the codomain. Hence morphisms do not so much map sets into sets, as embody a relationship between some posited domain and codomain.

    The notion of morphism recurs in much of contemporary mathematics. In set theory, morphisms are functions; in topology, continuous functions; in universal algebra, homomorphisms; in group theory, group homomorphisms.



    Statistical decision theory

    Several statistical tools and methods are available to organize evidence, evaluate risks, and aid in decision making. The risks of Type I and type II errors can be quantified (estimated probability, cost, expected value, etc) and rational decision making is improved.

    One example shows a structure for deciding guilt in a criminal trial:

      Actual condition
    Guilty Not guilty
    Decision Verdict of
    'guilty'    		 True Positive False Positive
     (i.e. guilt reported 
     unfairly) 
    Type I error
     Verdict of 
     'not guilty'     		 False Negative
     (i.e. guilt 
     not detected) 
    Type II error    		 True Negative


    Bayes' theorem



    Bayes' theorem relates the conditional and marginal probabilities of events A and B, where B has a non-vanishing probability:

    P(A|B) = \frac{P(B | A)\, P(A)}{P(B)}. </dd>

    Each term in Bayes' theorem has a conventional name:

    Intuitively, Bayes' theorem in this form describes the way in which one's beliefs about observing 'A' are updated by having observed 'B'.

    Dempster-Shafer theory

    The Dempster-Shafer theory is a mathematical theory of evidence that was introduced in the late 1970s by Glenn Shafer. It is a way of representing epistemic plausibilities. It developed from a sequence of works of Arthur Dempster , who was Shafer's advisor. In this formalism the best representation of chance is a belief function rather than a Bayesian probability distribution. Probability values are assigned to sets of possibilities rather than single events: their appeal rests on the fact they naturally encode evidence in favor of propositions. Shafer's framework allows for belief about propositions to be represented as intervals, taking on two values, support and plausibility, with support ≤ plausibility. Support for a hypothesis indicates the probability mass given to sets of events that are enclosed by it. Or in other words, it gives the amount of belief that directly supports a given hypothesis. Plausibility is 1 minus the masses given to sets of events whose intersection with the hypothesis results in an empty set. Again, in other words, it gives an upper bound on the belief that the hypothesis could possibly happen, i.e. it "could possibly happen" up to that value, because there was not any evidence that would contradict that hypothesis. For example, suppose we have a support of 0.5 and a plausibility of 0.8 for a proposition, say "the cat in the box is dead." This means that we have evidence that allows us to state strongly that the proposition is true with probability 0.5. However, the evidence contrary to that hypothesis (i.e. "the cat is alive") only has probability 0.2. This means that it is possible that the cat is alive, up to 0.8, since the remaining probability mass of 0.3 is essentially "indeterminate," meaning that the cat could either be dead or alive. Essentially this interval represents the level of uncertainty based off of the evidence in your system. Beliefs are combined using Dempster's rule of combination . Note that the probability masses from propositions that contradict each other can also be used to obtain a measure of how much conflict there is in a system. This measure has been used before as a criteria for clustering multiple pieces of seemingly conflicting evidence around competing hypotheses. In addition, one of the advantages of the Dempster-Shafer framework is that priors and conditionals need not be specified, unlike Bayesian methods which often map unknown priors to random variables (i.e. assigning 0.5 to binary values).

    Game Theory

    Game theory is a branch of applied mathematics that is used in the social sciences, most notably in economics, as well as in biology, engineering, political science, international relations, computer science, and philosophy. Game theory attempts to mathematically capture behavior in strategic situations, in which an individual's success in making choices depends on the choices of others. It has been expanded to treat a wide class of interactions, which are classified according to several criteria. Today, "game theory is a sort of umbrella or 'unified field' theory for the rational side of social science, where 'social' is interpreted broadly, to include human as well as non-human players (computers, animals, plants)" (Aumann 1987).

    Traditional applications of game theory attempt to find equilibria in these games. In an equilibrium, each player of the game has adopted a strategy that they are unlikely to change. Many equilibrium concepts have been developed (most famously the Nash equilibrium) in an attempt to capture this idea. These equilibrium concepts are motivated differently depending on the field of application, although they often overlap or coincide. This methodology is not without criticism, and debates continue over the appropriateness of particular equilibrium concepts, the appropriateness of equilibria altogether, and the usefulness of mathematical models more generally.

    Although some developments occurred before it, the field of game theory came into being with the 1944 book Theory of Games and Economic Behavior by John von Neumann and Oskar Morgenstern. This theory was developed extensively in the 1950s by many scholars. Game theory was later explicitly applied to biology in the 1970s, although similar developments go back at least as far as the 1930s. Game theory has been widely recognized as an important tool in many fields. Eight game theorists have won Nobel prizes in economics, and John Maynard Smith was awarded the Crafoord Prize for his application of game theory to biology.

    Uncertainty

    Uncertainty is a term used in subtly different ways in a number of fields, including philosophy, statistics, economics, finance, insurance, psychology, sociology, engineering, and information science. It applies to predictions of future events, to physical measurements already made, or to the unknown.

    Elemental Uncertainties

    Harmonic analysis is the branch of mathematics which studies the representation of functions or signals as the superposition of basic waves. It investigates and generalizes the notions of Fourier series and Fourier transforms. The basic waves are called " harmonics", hence the name "harmonic analysis." In the past two centuries, it has become a vast subject with applications in areas as diverse as signal processing, quantum mechanics, and neuroscience. The classical Fourier transform on Rn is still an area of ongoing research, particularly concerning Fourier transformation on more general objects such as tempered distributions. For instance, if we impose some requirements on a distribution f, we can attempt to translate these requirements in terms of the Fourier transform of f. The Paley-Wiener theorem is an example of this. The Paley-Wiener theorem immediately implies that if f is a nonzero distribution of compact support (these include functions of compact support), then its Fourier transform is never compactly supported. This is a very elementary form of an uncertainty principle in a harmonic analysis setting. See also classic harmonic analysis. Fourier series can be conveniently studied in the context of Hilbert spaces, which provides a connection between harmonic analysis and functional analysis.


    Catastrophe theory

    In mathematics, catastrophe theory is a branch of bifurcation theory in the study of dynamical systems; it is also a particular special case of more general singularity theory in geometry.

    Bifurcation theory studies and classifies phenomena characterized by sudden shifts in behavior arising from small changes in circumstances, analysing how the qualitative nature of equation solutions depends on the parameters that appear in the equation. This may lead to sudden and dramatic changes, for example the unpredictable timing and magnitude of a landslide.

    Catastrophe theory, which was originated with the work of the French mathematician René Thom in the 1960s, and became very popular due to the efforts of Christopher Zeeman in the 1970s, considers the special case where the long-run stable equilibrium can be identified with the minimum of a smooth, well-defined potential function (Lyapunov function).

    Small changes in certain parameters of a nonlinear system can cause equilibria to appear or disappear, or to change from attracting to repelling and vice versa, leading to large and sudden changes of the behaviour of the system. However, examined in a larger parameter space, catastrophe theory reveals that such bifurcation points tend to occur as part of well-defined qualitative geometrical structures.


    Fuzzy logic

    Fuzzy logic is derived from fuzzy set theory dealing with reasoning that is approximate rather than precisely deduced from classical predicate logic. It can be thought of as the application side of fuzzy set theory dealing with well thought out real world expert values for a complex problem (Klir 1997).

    Degrees of truth are often confused with probabilities. However, they are distinct conceptually; fuzzy truth represents membership in vaguely defined sets, not likelihood of some event or condition. For example, if a 100-ml glass contains 30 ml of water, then, for two fuzzy sets, Empty and Full, one might define the glass as being 0.7 empty and 0.3 full.

    Logic Fallacies

    Formal fallacies are arguments that are fallacious due to an error in their form or technical structure.[1] All formal fallacies are specific types of non sequiturs.

    • Ad hominem: an argument that attacks the person who holds a view or advances an argument, rather than commenting on the view or responding to the argument.
    • Appeal to probability: assumes that because something could happen, it is inevitable that it will happen. This is the premise on which Murphy's Law is based.
    • Argument from fallacy: if an argument for some conclusion is fallacious, then the conclusion must be false.
    • Bare assertion fallacy: premise in an argument is assumed to be true purely because it says that it is true.
    • Base rate fallacy: using weak evidence to make a probability judgment without taking into account known empirical statistics about the probability.
    • Conjunction fallacy: assumption that an outcome simultaneously satisfying multiple conditions is more probable than an outcome satisfying a single one of them.
    • Correlative based fallacies
    • Fallacy of necessity: a degree of unwarranted necessity is placed in the conclusion based on the necessity of one or more of its premises.
    • False dilemma (false dichotomy): where two alternative statements are held to be the only possible options, when in reality there are more.
    • If-by-whiskey: An answer that takes side of the questioner's suggestive question.
    • Ignoratio elenchi (irrelevant conclusion or irrelevant thesis)
    • Homunculus fallacy: where a "middle-man" is used for explanation, this usually leads to regressive middle-man. Explanations without actually explaining the real nature of a function or a process.
    • Masked man fallacy: the substitution of identical designators in a true statement can lead to a false one.
    • Naturalistic fallacy: a fallacy that claims that if something is natural, then it is "good" or "right".
    • Nirvana fallacy: when solutions to problems are said not to be right because they are not perfect.
    • Negative Proof fallacy: that, because a premise cannot be proven false, the premise must be true; or that, because a premise cannot be proven true, the premise must be false.
    • Package-deal fallacy: consists of assuming that things often grouped together by tradition or culture must always be grouped that way
    • Red Herring: also called a "fallacy of relevance." This occurs when the speaker is trying to distract the audience by arguing some new topic, or just generally going off topic with an argument.

    Propositional fallacies:

    Quantificational fallacies:

    • Existential fallacy: an argument has two universal premises and a particular conclusion, but the premises do not establish the truth of the conclusion.
    • Proof by example: where things are proven by giving an example.

    Syllogistic fallacies are logical fallacies that occur in syllogisms.

    Informal fallacies are arguments that are fallacious for reasons other than structural ("formal") flaws.

    • Argument from repetition (argumentum ad nauseam): signifies that it has been discussed extensively (possibly by different people) until nobody cares to discuss it anymore
    • Appeal to ridicule: a specific type of appeal to emotion where an argument is made by presenting the opponent's argument in a way that makes it appear ridiculous
    • Argument from ignorance ("appeal to ignorance"): The fallacy of assuming that something is true/false because it has not been proven false/true. For example: "The student has failed to prove that he didn't cheat on the test, therefore he must have cheated on the test."
    • Begging the question ("petitio principii"): where the conclusion of an argument is implicitly or explicitly assumed in one of the premises
    • Burden of proof: refers to the extent to which, or the level of rigour with which, it is necessary to establish, demonstrate or prove something for it to be accepted as true or reasonable to believe
    • Circular cause and consequence: where the consequence of the phenomenon is claimed to be its root cause
    • Continuum fallacy (fallacy of the beard): appears to demonstrate that two states or conditions cannot be considered distinct (or do not exist at all) because between them there exists a continuum of states. According to the fallacy, differences in quality cannot result from differences in quantity.
    • Correlation does not imply causation (cum hoc ergo propter hoc): a phrase used in the sciences and the statistics to emphasize that correlation between two variables does not imply that one causes the other
    • Equivocation (No true Scotsman): the misleading use of a term with more than one meaning (by glossing over which meaning is intended at a particular time)
    • Fallacies of distribution
      • Division: where one reasons logically that something true of a thing must also be true of all or some of its parts
      • Ecological fallacy: inferences about the nature of specific individuals are based solely upon aggregate statistics collected for the group to which those individuals belong
    • Fallacy of many questions (complex question, fallacy of presupposition, loaded question, plurium interrogationum): someone asks a question that presupposes something that has not been proven or accepted by all the people involved. This fallacy is often used rhetorically, so that the question limits direct replies to those that serve the questioner's agenda.
    • Fallacy of the single cause ("joint effect", or "causal oversimplification"): occurs when it is assumed that there is one, simple cause of an outcome when in reality it may have been caused by a number of only jointly sufficient causes.
    • False attribution: occurs when an advocate appeals to an irrelevant, unqualified, unidentified, biased or fabricated source in support of an argument
    • False compromise/middle ground: asserts that a compromise between two positions is correct
    • Gambler's fallacy: the incorrect belief that the likelihood of a random event can be affected by or predicted from other, independent events
    • Historian's fallacy: occurs when one assumes that decision makers of the past viewed events from the same perspective and having the same information as those subsequently analyzing the decision. It is not to be confused with presentism, a mode of historical analysis in which present-day ideas (such as moral standards) are projected into the past.
    • Incomplete comparison: where not enough information is provided to make a complete comparison
    • Inconsistent comparison: where different methods of comparison are used, leaving one with a false impression of the whole comparison
    • Intentional fallacy: addresses the assumption that the meaning intended by the author of a literary work is of primary importance
    • Moving the goalpost (raising the bar): argument in which evidence presented in response to a specific claim is dismissed and some other (often greater) evidence is demanded
    • Perfect solution fallacy: where an argument assumes that a perfect solution exists and/or that a solution should be rejected because some part of the problem would still exist after it was implemented
    • Post hoc ergo propter hoc: also known as false cause, coincidental correlation or correlation not causation.
    • Proof by verbosity (argumentum verbosium)
    • Prosecutor's fallacy: a low probability of false matches does not mean a low probability of some false match being found
    • Psychologist's fallacy: occurs when an observer presupposes the objectivity of his own perspective when analyzing a behavioral event
    • Regression fallacy: ascribes cause where none exists. The flaw is failing to account for natural fluctuations. It is frequently a special kind of the post hoc fallacy.
    • Reification (hypostatization): a fallacy of ambiguity, when an abstraction (abstract belief or hypothetical construct) is treated as if it were a concrete, real event or physical entity. In other words, it is the error of treating as a "real thing" something which is not a real thing, but merely an idea.
    • Retrospective determinism (it happened so it was bound to)
    • Special pleading: where a proponent of a position attempts to cite something as an exemption to a generally accepted rule or principle without justifying the exemption
    • Suppressed correlative: an argument which tries to redefine a correlative (two mutually exclusive options) so that one alternative encompasses the other, thus making one alternative impossible
    • Wrong direction: where cause and effect are reversed. The cause is said to be the effect and vice versa.

    Faulty generalizations:

    • Accident (fallacy): when an exception to the generalization is ignored
    • Cherry picking: act of pointing at individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position
    • Composition: where one infers that something is true of the whole from the fact that it is true of some (or even every) part of the whole
    • Dicto simpliciter
      • Converse accident (a dicto secundum quid ad dictum simpliciter): when an exception to a generalization is wrongly called for
    • False analogy: false analogy consists of an error in the substance of an argument (the content of the analogy itself), not an error in the logical structure of the argument
    • Hasty generalization (fallacy of insufficient statistics, fallacy of insufficient sample, fallacy of the lonely fact, leaping to a conclusion, hasty induction, secundum quid)
    • Loki's Wager: insistence that because a concept cannot be clearly defined, it cannot be discussed
    • Misleading vividness: involves describing an occurrence in vivid detail, even if it is an exceptional occurrence, to convince someone that it is a problem
    • Overwhelming exception (hasty generalization): It is a generalization which is accurate, but comes with one or more qualifications which eliminate so many cases that what remains is much less impressive than the initial statement might have led one to assume
    • Pathetic fallacy: when an inanimate object is declared to have characteristics of animate objects
    • Spotlight fallacy: when a person uncritically assumes that all members or cases of a certain class or type are like those that receive the most attention or coverage in the media
    • Thought-terminating cliché: a commonly used phrase, sometimes passing as folk wisdom, used to quell cognitive dissonance.

    A red herring is an argument, given in response to another argument, which does not address the original issue. See also irrelevant conclusion

    • Ad hominem: attacking the personal instead of the argument. A form of this is reductio ad Hitlerum.
    • Argumentum ad baculum ("appeal to force", "appeal to the stick"): where an argument is made through coercion or threats of force towards an opposing party
    • Argumentum ad populum ("appeal to belief", "appeal to the majority", "appeal to the people"): where a proposition is claimed to be true solely because many people believe it to be true
    • Association fallacy (guilt by association)
    • Appeal to authority: where an assertion is deemed true because of the position or authority of the person asserting it
    • Appeal to consequences: a specific type of appeal to emotion where an argument that concludes a premise is either true or false based on whether the premise leads to desirable or undesirable consequences for a particular party
    • Appeal to emotion: where an argument is made due to the manipulation of emotions, rather than the use of valid reasoning
      • Appeal to fear: a specific type of appeal to emotion where an argument is made by increasing fear and prejudice towards the opposing side
      • Wishful thinking: a specific type of appeal to emotion where a decision is made according to what might be pleasing to imagine, rather than according to evidence or reason
      • Appeal to spite: a specific type of appeal to emotion where an argument is made through exploiting people's bitterness or spite towards an opposing party
      • Appeal to flattery: a specific type of appeal to emotion where an argument is made due to the use of flattery to gather support
    • Appeal to motive: where a premise is dismissed, by calling into question the motives of its proposer
    • Appeal to novelty: where a proposal is claimed to be superior or better solely because it is new or modern
    • Appeal to poverty (argumentum ad lazarum): thinking a conclusion is correct because the speaker is financially poor or incorrect because the speaker is financially wealthy
    • Appeal to wealth (argumentum ad crumenam): concluding that a statement is correct because the speaker is rich or that a statement is incorrect because the speaker is poor
    • Argument from silence (argumentum ex silentio): a conclusion based on silence or lack of contrary evidence
    • Appeal to tradition: where a thesis is deemed correct on the basis that it has a long-standing tradition behind it
    • Chronological snobbery: where a thesis is deemed incorrect because it was commonly held when something else, clearly false, was also commonly held
    • Genetic fallacy: where a conclusion is suggested based solely on something or someone's origin rather than its current meaning or context. This overlooks any difference to be found in the present situation, typically transferring the positive or negative esteem from the earlier context.
    • Judgmental language: insultive or pejorative language to influence the recipient's judgment
    • Poisoning the well: where adverse information about a target is pre-emptively presented to an audience, with the intention of discrediting or ridiculing everything that the target person is about to say
    • Sentimental fallacy: it would be more pleasant if; therefore it ought to be; therefore it is
    • Straw man argument: based on misrepresentation of an opponent's position
    • Style over substance fallacy: occurs when one emphasizes the way in which the argument is presented, while marginalizing (or outright ignoring) the content of the argument
    • Texas sharpshooter fallacy: information that has no relationship is interpreted or manipulated until it appears to have meaning
    • Two wrongs make a right: occurs when it is assumed that if one wrong is committed, another wrong will cancel it out
    • Tu quoque: the argument states that a certain position is false or wrong and/or should be disregarded because its proponent fails to act consistently in accordance with that position

    Conditional or questionable fallacies 

    • Definist fallacy: involves the confusion between two notions by defining one in terms of the other
    • Luddite fallacy: related to the belief that labour-saving technologies increase unemployment by reducing demand for labour
    • Broken window fallacy: an argument which disregards hidden costs associated with destroying property of others.
    • Slippery slope: argument states that a relatively small first step inevitably leads to a chain of related events culminating in some significant impact

    Kinesics

    Kinesics is the interpretation of body language such as facial expressions and gestures — or, more formally, non-verbal behavior related to movement, either of any part of the body or the body as a whole.

    The term was first used (in 1952) by Ray Birdwhistell, a ballet dancer turned anthropologist who wished to study how people communicate through posture, gesture, stance, and movement. Part of Birdwhistell's work involved making film of people in social situations and analyzing them to show different levels of communication not clearly seen otherwise. The study was joined by several other anthropologists, including Margaret Mead and Gregory Bateson.

    Drawing heavily on descriptive linguistics, Birdwhistell argued that all movements of the body have meaning (ie. are not accidental), and that these non-verbal forms of language (or paralanguage) have a grammar that can be analysed in similar terms to spoken language. Thus, a "kineme" is "similar to a phoneme because it consists of a group of movements which are not identical, but which may be used interchangeably without affecting social meaning" (Knapp 1972:94-95).

    Birdwhistell estimated that "no more than 30 to 35 percent of the social meaning of a conversation or an interaction is carried by the words." He also concluded that there were no universals in these kinesic displays - a claim disputed by Paul Ekman's analysis of universals in facial expression.


    Genetic memory

     

    In molecular biology, genetic memory resides in the genetic material of the cell and is expressed via the genetic code used to translate it into proteins.[1][2] The genetic code enables cells to decode the information needed to construct the protein molecules that make up living cells and therefore record and store a one-dimensional blueprint for all the parts that make up an organism. This blueprint or genetic memory in the form of species-specific collections of genes (genotype or genome) is passed on from cell to cell and from generation to generation in the form of DNA molecules. DNA therefore functions as both a template for protein synthesis and as a biological clock.[2] Genetic memory can be modified by epigenetic memory, a process by which changes in gene expression are passed on through mitosis or meiosis through factors other than DNA sequence.


    Case Study: Angel Pringle

    “‘Evidence is unfairly prejudicial when there exists a danger that marginally probative evidence will be given undue or preemptive weight by the jury.’” 

    ...However, because it is pertinent to defendant’s assertion that she received ineffective assistance of counsel, we note that voluntary manslaughter is a killing performed in the heat of passion caused by adequate provocation and without sufficient time for a reasonable person to control that passion. People v Tierney, 266 Mich App 687, 714; 703 NW2d 204 (2005). Defendant’s theory of her case was that she acted in self-defense, not out of passion caused by reasonable provocation. A voluntary manslaughter instruction would not be compatible with defendant’s theory of her case or her own testimony. The trial court did not err by failing to give a voluntary manslaughter instruction.


    <td> </td>                      

    The Fight or Flight Response to Stress

    Stress is what happens to the body when any "pleasant" or "unpleasant" demand is placed upon it.

    The human body has an inborn, "pre-wired" response for dealing with dangerous situations - it is called the "fight or flight" response. Both fighting and fleeing require the same activities on the part of the body's organs.  The purpose of this response is to prepare the individual for vigorous muscular activity in response to a perceived threat.  By itself, this response is normal, healthy, and adaptive.  It is when the "fight/flight" response occurs too frequently or is greatly prolonged that we begin to experience the negative effects of stress.

    The human nervous system has a component that works automatically (the autonomic nervous system).  The autonomic nervous system has two divisions:  the 'sympathetic' and 'parasympathetic' divisions.  When the sympathetic division is active we experience the fight/flight response.  Interestingly, when the parasympathetic division is active we experience something quite opposite from "fight/flight" --- parasympathetic activity results in a response of rest & relaxation.  These two systems work to help us maintain our physical balance.

    Too much "fight/flight" activity without corresponding rest and relaxation is what distress is all about.

    POTENTIAL AUTONOMIC NERVOUS SYSTEM RESPONSES

    ORGAN OR FUNCTION "FIGHT/FLIGHT" (sympathetic) "REST/RELAXATION" (parasympathetic)
    Heart rate  increased decreased
    Arteries
       peripheral
       deep  
    constricted
    dilated  
    dilated
    -------
    Blood pressure increased decreased
    Blood sugar  increased -------
    Respiration rate increased decreased
    Gastro-intestinal activity decreased increased
    Skin
       sweat glands
       hair follicles
    increased activity
    contract/erect
    decreased activity
    relaxed
    Pupils dilation contraction
    http://olin.msu.edu/thefightorflightresponsetostress.php



    External Links:



    These results demonstrate that changes in histone phosphorylation in the hippocampus are regulated by ERK/MAPK following a behavioral fear conditioning paradigm. 

    http://www.learnmem.org/cgi/content/full/13/3/322

     

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