Saturday, October 29, 2011

学習性無力感 [英]Learned Helplessness他

Russell A. Powell, et al.  Introduction to Learning and Behavior, 3rd Edition. 2009

"Masserman’s Experimental Neurosis"「実験神経症」
As a general rule, traumatic symptoms are more easily induced in animals when the aversive stimulus is delivered in an environment that the animal has long associated with safety or some type of appetitive event.  For example, unpredictable shocks delivered in a setting in which the animal typically eats food are especially likely to induce neurotic symptoms (Masserman, 1943).  This suggests that symptoms of PTSD are more likely to arise when a person is, for example, unexpectedly attacked in the safety of his or her own home as opposed to a strange or dangerous area of town.  The person who is attacked at home generalizes the experience and perceives the world at large as a dangerous, unpredictable place, with the resultant that he or she thereafter remains constantly vigilant (369). 
 

"Learned Helplessness"「学習性無力感」
Learned Helplessness has also been related to certain forms of depression (Seligman, 1975).  People who suffer a series of uncontrollable aversive events – loss of a job, pysically illness, divorce, and so on – may become extremely passive and despondent.  Like animals exposed to inescapable shock, they show little interest in improving their lot in life (366).
Researchers have discovered a way to eliminate learned helplessness...behavioral treatments for depression often involve encouraging the patient to accomplish a graded series of tasks, starting with relatively minor task, such as writing a letter, and progressing to more difficult tasks, such as seeking a new job (Seligman, 1975).
Researchers also suggested…that a history of successfully overcoming minor adversities might immunize a person against depression when the person is later confronted by more serious difficulties (366-7)
 (Experiment of  Learned Helplessness by Nixon, Ph.D Developmental Psychologist at Penn State)

"Sensitizatization"鋭敏化」
Sensitizatization is an increase in the strength of an elicited behavior following repeated presentations of the eliciting stimulus.  For example, soldiers under attack generally do not habituate to the sound of artillery shells exploding nearby.  Instead, their startle reaction grows stronger.  Needless to say, this greatly contributes to the stress they experience and the inevitable breakdown virtually all soldiers suffer after repeated exposure to battle conditions (though Hollywood would often have you think otherwise)(97).


Watson and Rayner’s “Little Albert” 「アルバート坊や実験」

The importance of classical conditioning and overgeneralization in the development of phobia was first noted by John B. Watson and his student Rosalie Rayner.…they attempt[ed] to condition a fear response in an 11-month-old infant named Albert.

   Watson and Rayner (1920) paired the loud noise with the white rat (Neutral Stimulus).  Albert “jumped violently and fell forward, burying his face in the matress”...Albert was then subjected to further pairings of the rat with noise, during which he became more and more fearful. 

   Albert showed not only a fear of the rat but also of objects that were in some way similar to the rat, such as a rabbit, a fur coat, a dog, and even a Santa Claus mask.  In other words, Albert’s fear response had generalized to objects that were similar to the original CS (conditioned stimulus). 

  By contrast, real-life phobias usually require only one paring of the US (unconditioned stimulus) with the CS to become established, and they often grow stronger over time (182-5).  

   


Latent Inhibition
    The phenomenon whereby a familiar stimulus is more difficult to condition as a CS than is an unfamiliar (novel) stimulus (151).
           

実験神経症 [英]experimental neurosis

『精神医学事典』加藤正明、保崎秀夫ほか編集

実験神経症 []experimental neurosis

パブロフI.P. Pavlovの研究以来実験精神病理学者の関心を引き、多くの研究がなされてきたがその現象は多義的である。被験体としては犬、猫、山羊、豚、猿、白ネズミ、魚類などが主だが、人間の子供も用いられた。症状としては元来静かな生体が興奮し、学習は崩れ不安定となり、激しい運動暴発や攻撃または強い制止状態におち入り、長期にわたり回復安定することがない。発生条件としては、(1)強い電撃で唾液条件反射を形成し、その刺激部位を移動した場合(Yerofeevaの実験)(2)弁別不能の近似刺激間になお弁別を強制した場合(Shenger-Krestovnikova)(3)興奮型の生体に延滞条件づけ時間を延ばしていった場合(Petrova),(4)制止型の生体に過緊張を強いる危険的刺激が急激に加わった場合(Speransky),(5)拘束状態でストレス刺激が慢性的に加わり、その覚度が生体の耐性を越えた場合(Liddell), (6)神経症への情動的認知的な生得的傾性(Gantt, Dykman),(7)閉鎖空間での有害刺激(Massermanに対するウォルピWolpeやスマートSmartの反証実験)(8)分化条件づけ形成後に条件刺激間の意味を逆転させる"条件性スイッチィング"を繰り返して条件づけを続けていく場合(E. A. Asratyan, 拓植)などの条件が抽出されている。