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تحقیق درموردمتن انگلیسی آداب و رسوم خراسان

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تعداد صفحات: 17

 

نهبندان پارچه بافی

پارچه بافی در تمام نقاط استان خراسان انجام میشود. بافت پارچه هایی برای تهیه و دوخت انواع البسه مردانه و زنانه ، بافت حوله- جابندو...از وظایف سنگینی است که برعهدة زنان می باشد. فرتی farati و کرباس دو اصطلاح عمومی است که به محصولات أین کارگاهها اطلاق میشود امروزه با رواج استفاده از پارچه های ارزان قیمت و رنگارنگ کارگاهها ی پارچه بافی نیز از کار افتاده اند. کارگاههای کوچک چوبی که در گوشه اتاق نشیمن همه خانه های روستایی هنوز جای خالی اش بچشم می خورد و با در مناطق دور افتاده هنوز برای بافت حوله مورد استفاده قرار می گیرد

شمال خراسان بافت نوارهای تزیینی

به عمل بافت نوارهای تزئینی در شمال خراسان مداخل بافی با جهره بافی میگویند کارگاه بافت مداخل از جنس چوب ساخته میشود. هریک از نخهای تار به یک صفحه چهار گوش از جنس پوست و یا امروزه نگاتیو عکسهای رادیولوژی وصل شده استو بافنده تا تغییر وضعیت هریک از صفحه ها به نقش پردازی بر روی نوار مبادرت می ورزد.

قوچان پوستین دوزی

زندگی دامداری و کوچ نشینی همراه با سردی هوا در شمال خراسان سبب رواج استفاده از پوستین و در نتیجه پوستین دوزی شده است.

قوچان پوستین دوزی

هوای سرد و دام فراوان قوچان أین صنعت دستی را بوجود آورده است، پوستین دوزی یک صنعت سنتی و قدیمی است. پوستین های قوچان در میان دامداران شمال خراسان معروف است. پوستین دوزی از مشاغلی است که افراد خاصی به آن مبادرت می ورزند که اجدادشان برای آنها به ارث گذاشته اند ، مرکز اصلی و مهم آن قوچان است. استفاده از پوستین در اکثر شهرهای شمالی خراسان در فصول سرد رایج است. در حال حاضر در قوچان یک نفر به أین حرفه اشتغالف دارد که اجدادش یکی دو نسل قبل از او از أین راه امرار معاش می کردند. کار تهیه پوست که جزو مراحل اولیه می باشد بر عهده خود پوستین دوز است.

گناباد نمد مالی

یکی از صنایع دستی است که در حال حاضر در روستای بیمورق که بطور اجمال مورد پژوهش قرار گرفته تهیه می گردد. عمده کار نمد مال این روستا تهیه و مالیدن نمد چوپانی است که در زمستان از آن استفاده می کنند. مواد اولیه نمد مالی پشم گوسفندان می باشد که آنرا از دامداران می خرند پس از تهیه پشم آنرا با کما ن حلاجی که خود نمد مالان در اختیار دارند حلاجی می کنند تا آماده کار شود .

سبد بافی

از صنایع دستی دیگر سبد بافی است که در یکی از روستاهای دیگری که بطور اجمال مورد پژوهش قرار کرفته معمول می باشد خانیک از روستا های مناطق سردسیر و ییلاقی گناباد می باشد که در طول این تحقیق برآن نگاهی انداخته شده است. سبد بافی در این روستا بعنوان یک منبع درآمد برای برخی از اهالی میباشد که در حال حاضر بندرت دیده می شود. مواد اولیه سبد بافی چوبهای نازک و طویل درخت بید می باشد که از آن وسایل زیر را بدست می آورند .

سرخس نجاری

یکی از فنون و صنایعی که در گذشته در بعضی از روستاها و شهر سرخس رایج بوده است. نجاری سنتی با روش و وسایل ابتدایی بوده است که در حال حاضر در روستاها بجز بزنگان و شهر سرخس و آن هم با فنون و روشهای جدید، در سایر روستاهای مورد پژوهش ازبین رفته و اثری از آن دیده نمی شود. نجاران سنتی ، ساختن در بهای خانه، پنجره ها ، کمد ، صندوقچه جهت لباسها ، دسته بیل و کلنگ ، میخ زدن و تراشیدن چوب جهت سقف خانه ها را در گذشته برعهده داشته اند، که در بعضی از روستاها مثل قره قیطان ، اسلام قلعه بخاری محلی وجود نداشته و کارهای نجاریشان را نجاران دوره گرد انجام می داده اند.

نیشابو قالی بافی

یکی از معمولترین صنایع دستی که در گذشته به وفور در کلیه مناطق بررسی شده رایج بوده قالی بافی است. قالی بافی که در گذشته رایج بوده با قالی بافی امروزی تفاوت داشته است . در زمانهای قبل دستگاههای قالی بافی بصورت افقی و بر روی زمین دایر می شده که متشکل از دو تیر چوب بوده و در فاصله ای معین به چهار میخ آهنی بلندکه در چهار نقطه متقابل به زمین کوبیده می شد می بستند. مواد اولیه : در کلیه مناطق مواد اولیه این نوع قالی بافی را از پشم گوسفندان تهیه می نمودند پشم را بعد از چیدن از بدن حیوانات شستشو می دادند و بعد با رنگهای گیاهی آنرا رنگ می زدند و بوسیله جلک و چرخ به نخ تبدیل می کردند و بدون اینکه نقشه ای بکار ببرند می بافتند. ابزاری که در قالی بافی گذشته و حال مورد استفاده قرار می گیرد پاکی وسیله ای جهت بریدن رنگ یا نخ در موقع بافتن - افه یا به اصطلاح استاد استوک جهت ضربه زدن بر لبه قالی - قیچی یا مقراض. امروزه قالی بافی در تمام مناطق بوسیله دستگاههای آهنی عمودی انجام می گیرد که بر اساس نقشه ای از قبل در بازار شهر تهیه می کنند می بافند.

فردوس آهنگری

 این حرفه که در گذشته وظیفه تامین ابزار فلزی را برعهده داشت اکنون نیز به دلیل کاربرد برخی صنایع سنتی در شهرستان به حیات خویش ادامه می دهد . کارگاههای آهنگری سنتی در شهر فردس بصورت محدود وجود دارد. جوانان به این حرفه علاقه چندانی ندارند اما به لحاظ اینکه کوبیدن پتک بر روی آهن گداخته به نیروی فراوانی محتاج است هر استاد کار از نیروی یک جوان در این عمل بهره می گیرد . ابزار مورد نیاز آهنگر عبارتند از: دم آهنگری یا دستگاه : از دوصفح چوبی با پرده های پوستی ویک محل بعنوان کوره تشکیل یافته ااست. این سیستم که در گذشته ( تا حدود 30 سال پیش ) کاربد داشته است. جهت دم دادن نیاز به یک نیروی انسانی دارد. با حرکت دم ، بادبه محل کوره هدایت می شود و زغال سنگ را می گذارد تا حرارت کافی جهت گداختن آهن تامین شود. امروزه اهنگرها از دم برقی استفاده می کنند

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تحقیق درموردمتن انگلیسی آداب و رسوم خراسان

تحقیق درموردمتن انگلیسی آینده خانواده در غرب 5ص

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آینده خانواده در غرب

مک دانولد در مقاله خود به نقد تئوری همگرایی ساختار خانواده می پردازد. ویلیام گود، ارائه دهنده این تئوری در کتابش به نام انقلاب جهانی و الگوهای خانواده، پیش بینی کرده بود که همگرایی اجتناب ناپذیری در سیستم خانواده وجود دارد و تمام اشکال خانواده به شکل خانواده زن وشوهری غرب در خواهند آمد.

 

مک دانولد در مقاله خود به نقد تئوری همگرایی ساختار خانواده می پردازد. ویلیام گود، ارائه دهنده این تئوری در کتابش به نام انقلاب جهانی و الگوهای خانواده، پیش بینی کرده بود که همگرایی اجتناب ناپذیری در سیستم خانواده وجود دارد و تمام اشکال خانواده به شکل خانواده زن وشوهری غرب در خواهند آمد.

از نظر گود یک هماهنگی تئوریکی بین سیستم خانواده زن و شوهری و جهان مدرن وجود داشت. او از این نظر دنباله رو پارسونز بود و زمان این تغییر را نیز ده تا بیست سال آینده می دانست، (زمانی که اکنون دیگر سپری شده است). طبق این نظر فرایند مدرن شدن جوامع اصلی بدیهی در نظر گرفته می شود و برای تبیین رشد خانواده هسته ای نیز از همین اصل استفاده می شود.

خانواده هسته ای مدرن همان طور که پارسونز و میلز گفته اند، به وسیله جدایی (انزوای ساختاری ) و تفکیک خشک نقش های زن و شوهر توصیف می شود. این مشخصات، خانواده هسته ای را برای عمل در جهان مدرن بهتر تجهیز می کند.

در مقاله آمده، گود و پارسونز هر دو به مارکس و وبر مدیونند چرا که آنها می گویند جامعه و ساختارهای آن از طریق دوره انقلابی در مراحل پیشرفته سرمایه داری تغییر می کنند. شهری شدن، صنعتی شدن، فرد گرایی و... عوامل تسلط خانواده هسته ای هستند. در ادامه مک دانولد هر چهار نفر یعنی گود، پارسونز، مارکس و وبر را مرهون اطلاعات نادرست تاریخ خانواده در اروپای غربی می داند.

نویسنده بین خانواده زن و شوهری و خانواده هسته ای با وجود هم مرز بودنشان فرق می گذارد، ((واژه هسته ای توسط پارسونز استفاده می شده اما غیر قابل پذیرش است زیرا معنی ضمنی آن این است که واحد زن و شوهر و فرزندانشان، کوچکترین خانواده ممکن یا گروه خویشاوندی را به وجودمیآورد)).

او اصطلاح گود یعنی خانواده زن وشوهری را ترجیح داده و می نویسد: گود خانواده زن وشوهری چند زنی را نادیده گرفت و تئوری همگرایی را فراتر از بعد ساختاری، و به ابعاد کارکردی گسترش داد. گود و پارسونز به خانواده زناشویی غربی دهه ۱۹۵۰ مراجعه کردند و آن را مستقل از دیگر خانواده ها، متمرکز و دارای نقش های تفکیک شده خشک زن وشوهر دیدند. بنابراین اثبات تئوری همگرایی به پیدایش این شکل از خانواده بستگی دارد.

این تئوری متکی بر این نظر است که تغییر سیستم خانواده به عنوان نتیجه اجتناب ناپذیر تغییرات ساختاری و ایدئولوژیکی است، تغییرات ساختاری مانند صنعتی شدن، شهری شدن، پرولتاریزه شدن و تمرکز قدرت. تغییرات ایدئولوژیکی اجتناب ناپذیر نیز، پذیرش ارزشهای خانواده غربی دهه ۱۹۵۰ است. اصل موضوع تئوری این است که تغییرات کلان ساختاری غربی بوده بنابراین تغییرات خرد نیز لزوما غربی است.

نویسنده ۴ فرض در ارتباط با رد یا قبول این تئوری مطرح می کند:

۱) مدل درست است اما فرایند تغییرات کندتر از آن است که دیده شود.

۲) تغییرات کلان از فرایند تکامل پیش بینی شده توسط طرفداران این نظریه پیروی نمی کند.

۳) تغییر اجتماعی یک جهتی و از کلان به خرد نیست.

۴) سیستم خرد وکلان به طور انعطاف ناپذیری، آن طور که طرفداران این نظریه پافشاری می کنند، به هم متصل نمی شوند.

حال اگر نظر اول درست باشد، نظریه همگرایی درست است، اگر نظر دوم صحیح باشد قابل بخشش است و اگر نظرات سوم یا چهارم درست باشد تئوری همگرایی رد می شود.

نویسنده معتقد است رد این نظریه به سادگی صورت می گیرد زیرا تنها کافی است نمونه های خلاف آنچه انگاره تئوری است، یعنی جهان شمولی، ذکر شود.

تحقیقات جدید بر شبکه های حمایتی خانواده در کشورهای غربی مشارکت بالاو متفاوتی را بین خانوارهای وابسته نشان می دهد که هرگز منزوی نبوده اند. ارث بری و کمکهای پدربزرگ و مادر بزرگ در نگهداری از فرزندان، کمک والدین به فرزندان تازه ازدواج کرده، حمایت از سالخوردگان، حرفه های مشارکتی خویشاوندی، برگشت فرزندان به خانواده ها در صورت از هم پاشیده شدن ازدواج، کمک های خویشاوندان به یکدیگر در صورت بروز بحران و حمایت عاطفی اعضا از یکدیگر، همه نشان دهنده عدم انزوای خانواده ها در غرب است. علاوه بر این تکرار این مشارکت های خویشاوندی درشکل و شدت، در بین جوامع غیر غربی هم خود تایید دیگری بر این استدلال است. مثلا اپونگ برخی نمونه ها را نشان داد که اقتصاد خارج از چارچوب خانواده زن و شوهری داشتند و مراقبت از کودکان بوسیله افراد خارج از خانوار زن و شوهری صورت می گرفت. آرنولد هم در ۱۹۸۴ تفاوت های قابل توجهی در درجه مشارکت میان گروههای به رسمیت شناخته شده خانواده های وابسته در انجام وظایف میان خانوار گزارش داد. کمپبل نیز قدرت احساس وظیفه فرزندان ژاپنی در حمایت از والدین پیرشان را نشان داد.


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تحقیق درموردمتن انگلیسی آینده خانواده در غرب 5ص

تحقیق درموردمتن انگلیسی الکسنادر هامبل انگلیسی

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تعداد صفحات: 17

 

Alexander Graham Bell (3 March 1847 – 2 August 1922) was an eminent scientist, inventor and innovator who is credited with inventing the first practical telephone.

Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell's life's work.[1] His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first U.S. patent for the telephone in 1876.[2] In retrospect, Bell considered his most famous invention an intrusion on his real work as a scientist and refused to have a telephone in his study.[3]

Many other inventions marked Bell's later life, including groundbreaking work in hydrofoils and aeronautics. In 1888, Alexander Graham Bell became one of the founding members of the National Geographic Society.[4

Early years

Alexander Bell was born in Edinburgh, Scotland on 3 March 1847.[5] The family home was at 16 South Charlotte Street, Edinburgh, Scotland, and now has a commemorative marker at the doorstep, marking it as Alexander Graham Bell's birthplace. He had two brothers: Melville James Bell (1845–1870) and Edward Charles Bell (1848–1867). Both of his brothers died of tuberculosis.[6] His father was Professor Alexander Melville Bell, and his mother was Eliza Grace (née Symonds).[7] Although he was born "Alexander", at age ten, he made a plea to his father to have a middle name like his two brothers.[8] For his 11th birthday, his father acquiesced and allowed him to adopt the middle name "Graham", chosen out of admiration for Alexander Graham, a Canadian being treated by his father and boarder who had become a family friend.[9] To close relatives and friends he remained "Aleck" which his father continued to call him into later life.[10]

First invention

As a child, young Alexander Graham Bell displayed a natural curiosity about his world, resulting in gathering botanical specimens as well as experimenting even at an early age. His best friend was Ben Herdman, a neighbour whose family operated a flour mill, the scene of many forays. Young Aleck asked what needed to be done at the mill. He was told wheat had to be dehusked through a laborious process and at the age of 12, Bell built a homemade device that combined rotating paddles with sets of nail brushes, creating a simple dehusking machine that was put into operation and used steadily for a number of years.[11] In return, John Herdman gave both boys the run of a small workshop within which to "invent".[11]

From his early years, Bell showed a sensitive nature and a talent for art, poetry and music that was encouraged by his mother. With no formal training, he mastered the piano and became the family's pianist.[12] Despite being normally quiet and introspective, he revelled in mimicry and "voice tricks" akin to ventriloquism that constantly entertained family guests.[12] Bell was also deeply affected by his mother's gradual deafness, (she began to lose her hearing when he was 12) and learned a manual finger language so he could sit at her side and tap out silently the conversations swirling around the family parlour.[13] He also developed a technique of speaking in clear, modulated tones directly into his mother's forehead wherein she would hear him with reasonable clarity.[14] Bell's preoccupation with his mother's deafness led him to study acoustics.

His family was long associated with the teaching of elocution: his grandfather, Alexander Bell, in London, his uncle in Dublin, and his father, in Edinburgh, were all elocutionists. His father published a variety of works on the subject, several of which are still well known, especially his The Standard Elocutionist (1860)[12] Mackay 1997, , which appeared in Edinburgh in 1868. The Standard Elocutionist appeared in 168 British editions and sold over a quarter of a million copies in the United States alone. In this treatise, his father explains his methods of how to instruct deaf-mutes (as they were then known) to articulate words and read other people's lip movements to decipher meaning. Aleck's father taught him and his brothers not only to write Visible Speech but also to identify any symbol and its accompanying sound.[15] Aleck became so proficient that he became a part of his father's public demonstrations and astounded audiences with his abilities in deciphering Latin, Gaelic and even Sanskrit symbols.[15]

Education

As a young child, Bell, like his brothers, received his early schooling at home from his father. At an early age, however, he was enrolled at the Royal High School, Edinburgh, Scotland, which he left at age 15, completing the first four forms only.[16] His school record was undistinguished, marked by absenteeism and lacklustre grades. His main interest remained in the sciences, especially biology, while he treated other school subjects with indifference, to the dismay of his demanding father.[17] Upon leaving school, Bell travelled to London to live with his grandfather, Alexander Bell. During the year he spent with his grandfather, a love of learning was born, with long hours spent in serious discussion and study. The elder Bell took great efforts to have his young pupil learn to speak clearly and with conviction, the attributes that his pupil would need to become a teacher himself.[18] At age 16, Bell secured a position as a "pupil-teacher" of elocution and music, in Weston House Academy, at Elgin, Moray, Scotland. Although he was enrolled as a student in Latin and Greek, he instructed classes himself in return for board and £10 per session.[19] The following year, he attended the University of Edinburgh; joining his older brother Melville who had enrolled there the previous year.

First experiments with sound

Bell's father encouraged Aleck's interest in speech and, in 1863, took his sons to see a unique automaton, developed by Sir Charles Wheatstone based on the earlier work of Baron Wolfgang von Kempelen.[20] The rudimentary "mechanical man" simulated a human voice. Aleck was fascinated by the machine and after he obtained a copy of von Kempelen's book, published in German, and had laboriously translated it, he and his older brother Melville built their own automaton head. Their father, highly interested in their project, offered to pay for any supplies and spurred the boys on with the enticement of a "big prize" if they were successful.[20] While his brother constructed the throat and larynx, Aleck tackled the more difficult task of recreating a realistic skull. His efforts resulted in a remarkably lifelike head that could "speak", albeit only a few words.[20] The boys would carefully adjust the "lips" and when a bellows forced air through the windpipe, a very recognizable "Mama" ensued, to the delight of neighbors who came to see the Bell invention.[21]

Intrigued by the results of the automaton, Bell continued to experiment with a live subject, the family's Skye terrier, "Trouve".[22] After he taught it to growl continuously, Aleck would reach into its mouth and manipulate the dog's lips and vocal cords to produce a crude-sounding "Ow ah oo ga ma ma." With little convincing, visitors believed his dog could articulate "How are you grandma?" More indicative of his playful nature, his experiments convinced onlookers that they saw a "talking dog."[23] However, these initial forays into experimentation with sound led Bell to undertake his first serious work on the transmission of sound, using tuning forks to explore resonance. At the age of 19, he wrote a report on his work and sent it to Alexander Ellis, a colleague of his father.[23] Ellis immediately wrote back indicating that the experiments were similar to existing work in Germany. Dismayed to find that groundbreaking work had already been undertaken by Hermann von Helmholtz who had conveyed vowel sounds by means of a similar tuning fork "contraption", he pored over the German scientist's book, Sensations of Tone. From his translation of the original German edition, Aleck then made a deduction that would be the underpinning of all his future work on transmitting sound, "Without knowing much about the subject, it seemed to me that if vowel sounds could be produced by electrical means so could consonants, so could articulate speech."[24]

Family tragedy

In 1865, when the Bell family moved to London,[25] Bell returned to Weston House as an assistant master and, in his spare hours, continued experiments on sound using a minimum of laboratory equipment. Bell concentrated on experimenting with electricity to convey sound and later installed a telegraph wire from his room in Somerset College to that of a friend.[26] Throughout the fall and winter of 1867, his health faltered mainly through exhaustion. His younger brother, Edward "Ted," was similarly bed-ridden, suffering from tuberculosis. While Bell recovered (by then referring to himself in correspondence as "A.G. Bell") and served the next year as an instructor at Somerset College, Bath, Somerset, England, his brother's condition deteriorated. Edward would never recover. Upon his brother's passing, Bell returned home in 1867. His older brother, "Melly" had married and moved out. With aspirations to obtain a degree at the University College London, Bell considered his next years as preparation for the degree examinations, devoting his spare time at his family's residence to studying.

Helping his father in Visible Speech demonstrations and lectures brought Bell to Susanna E. Hull's private school for the deaf in South Kensington, London. His first two pupils were "deaf mute" girls who made remarkable progress under his tutelage. While his older brother seemed to achieve success on many fronts including opening his own elocution school, applying for a patent on an invention, and starting a family, Bell continued as a teacher. However, in May 1870, Melville died from complications due to tuberculosis, causing a family crisis. His father had also suffered a debilitating illness earlier in life and had been restored to health by a convalescence in Newfoundland. Bell's parents embarked upon a long-planned move when they realized that their remaining son was also sickly. Acting decisively, Alexander Melville Bell asked Bell to arrange for the sale of all the family property,[27] conclude all of his brother's affairs (Bell took over his last student, curing a pronounced lisp),[28] and join his father and mother in setting out for the "New World."[29] Reluctantly, Bell also had to conclude a relationship with Marie Eccleston, who, he had surmised, was not prepared to leave England with him.[29]

Canada

In 1870, at age 23, Bell, his brother's widow, Caroline (Margaret Ottaway),[30] and his parents travelled on the SS Nestorian to Canada.[31] After landing at Quebec City, the Bells boarded a train to Montreal and later to Paris, Ontario to stay with the Reverend Thomas Henderson, a family friend. After a brief stay with the Hendersons, the Bell family purchased a 10-and-a-half acre farm at Tutelo Heights (now called Tutela Heights), near Brantford, Ontario. The property consisted of an orchard, larger farm house, stable, pigsty, hen-house and a carriage house, which bordered the Grand River.[32]

At the homestead, Bell set up his own workshop in the converted carriage house[33] near to what he called his "dreaming place", a large hollow nestled in trees at the back of the property above the river.[34] Despite his frail condition upon arriving in Canada, Bell found the climate and environs to his liking, and rapidly improved.[35] He continued his interest in the study of the human voice and when he discovered the Six Nations Reserve across the river at Onondaga, he learned the Mohawk language and translated its unwritten vocabulary into Visible Speech symbols. For his work, Bell was awarded the title of Honorary Chief and participated in a ceremony where he donned a Mohawk headdress and danced traditional dances.[36]

After setting up his workshop, Bell continued experiments based on Helmholtz's work with electricity and sound.[33] He designed a piano, which, by means of electricity, could transmit its music at a distance. Once the family was settled in, both Bell and his father made plans to establish a teaching practice and in 1871, he accompanied his father to Montreal, where Melville was offered a position to teach his System of Visible Speech.

Work with the deaf

Subsequently, his father was invited by Sarah Fuller, principal of the Boston School for Deaf Mutes (which continues today as the public Horace Mann School for the Deaf),[37] in Boston, Massachusetts, United States, to introduce the Visible Speech System by providing training for Fuller's instructors, but he declined the post, in favor of his son. Traveling to Boston in April 1871, Bell provided a successful in servicing of the school's instructors.[38] He was subsequently asked to repeat the program at the American Asylum for Deaf-mutes in Hartford and the Clarke School for the Deaf in Northampton.

Returning home to Brantford after six months abroad, Bell continued his experiments with his "harmonic telegraph".[39] The basic concept behind his device was that messages could be sent through a single wire if each message was transmitted at a different pitch, but work on both the transmitter and receiver as needed.[40] Unsure of his future, he first contemplated returning to London to complete his studies, but


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Operant conditioning

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"Operant" redirects here. For the meaning of operant, see Operant.

Operant conditioning is the use of consequences to modify the occurrence and form of behavior. Operant conditioning is distinguished from Pavlovian conditioning in that operant conditioning deals with the modification of "voluntary behavior" through the use of consequences, while Pavlovian conditioning deals with the conditioning of behavior so that it occurs under new antecedent conditions.[1]

[edit] Reinforcement, punishment, and extinction

Reinforcement and punishment, the core tools of operant conditioning, are either positive (delivered following a response), or negative (withdrawn following a response). This creates a total of four basic consequences, with the addition of a fifth procedure known as extinction (i.e. no change in consequences following a response).

It's important to note that organisms are not spoken of as being reinforced, punished, or extinguished; it is the response that is reinforced, punished, or extinguished. Additionally, reinforcement, punishment, and extinction are not terms whose use are restricted to the laboratory. Naturally occurring consequences can also be said to reinforce, punish, or extinguish behavior and are not always delivered by people.

Reinforcement is a consequence that causes a behavior to occur with greater frequency.

Punishment is a consequence that causes a behavior to occur with less frequency.

Extinction is the lack of any consequence following a response. When a response is inconsequential, producing neither favorable nor unfavorable consequences, it will occur with less frequency.

Four contexts of operant conditioning: Here the terms "positive" and "negative" are not used in their popular sense, but rather: "positive" refers to addition, and "negative" refers to subtraction. What is added or subtracted may be either reinforcement or punishment. Hence positive punishment is sometimes a confusing term, as it denotes the addition of punishment (such as spanking or an electric shock), a context that may seem very negative in the lay sense. The four procedures are:

Positive reinforcement occurs when a behavior (response) is followed by a favorable stimulus (commonly seen as pleasant) that increases the frequency of that behavior. In the Skinner box experiment, a stimulus such as food or sugar solution can be delivered when the rat engages in a target behavior, such as pressing a lever.

Negative reinforcement occurs when a behavior (response) is followed by the removal of an aversive stimulus (commonly seen as unpleasant) thereby increasing that behavior's frequency. In the Skinner box experiment, negative reinforcement can be a loud noise continuously sounding inside the rat's cage until it engages in the target behavior, such as pressing a lever, upon which the loud noise is removed.

Positive punishment (also called "Punishment by contingent stimulation") occurs when a behavior (response) is followed by an aversive stimulus, such as introducing a shock or loud noise, resulting in a decrease in that behavior.

Negative punishment (also called "Punishment by contingent withdrawal") occurs when a behavior (response) is followed by the removal of a favorable stimulus, such as taking away a child's toy following an undesired behavior, resulting in a decrease in that behavior.

Also:

Avoidance learning is a type of learning in which a certain behavior results in the cessation of an aversive stimulus. For example, performing the behavior of shielding one's eyes when in the sunlight (or going indoors) will help avoid the punishment of having light in one's eyes.

Extinction occurs when a behavior (response) that had previously been reinforced is no longer effective. In the Skinner box experiment, this is the rat pushing the lever and being rewarded with a food pellet several times, and then pushing the lever again and never receiving a food pellet again. Eventually the rat would cease pushing the lever.

Non-contingent Reinforcement is a procedure that decreases the frequency of a behavior by both reinforcing alternative behaviors and extinguishing the undesired behavior. Since the alternative behaviors are reinforced, they increase in frequency and therefore compete for time with the undesired behavior.

[edit] Thorndike's Law of Effect

Operant conditioning, sometimes called instrumental conditioning or instrumental learning, was first extensively studied by Edward L. Thorndike (1874-1949), who observed the behavior of cats trying to escape from home-made puzzle boxes.[2] When first constrained in the boxes, the cats took a long time to escape. With experience, ineffective responses occurred less frequently and successful responses occurred more frequently, enabling the cats to escape in less time over successive trials. In his Law of Effect, Thorndike theorized that successful responses, those producing satisfying consequences, were "stamped in" by the experience and thus occurred more frequently. Unsuccessful responses, those producing annoying consequences, were stamped out and subsequently occurred less frequently. In short, some consequences strengthened behavior and some consequences weakened behavior. B.F. Skinner (1904-1990) formulated a more detailed analysis of operant conditioning based on reinforcement, punishment, and extinction. Following the ideas of Ernst Mach, Skinner rejected Thorndike's mediating structures required by "satisfaction" and constructed a new conceptualization of behavior without any such references. Moreover, Thorndike's work with puzzle boxes produced no meaningful data to be studied other than a measure of escape times. So while experimenting with some homemade feeding mechanisms Skinner invented the operant conditioning chamber which allowed him to measure rate of response as a key dependent variable using a cumulative record of lever presses or key pecks.[3]

[edit] Operant Conditioning vs Fixed Action Patterns

Skinner's construct of instrumental learning is contrasted with what Nobel Prize winning biologist Konrad Lorenz termed "fixed action patterns," or reflexive, impulsive, or instinctive behaviors. These behaviors were said by Skinner and others to exist outside the parameters of operant conditioning but were considered essential to a comprehensive analysis of behavior.

In dog training, the use of the prey drive, particularly in training working dogs, detection dogs, etc., the stimulation of these fixed action patterns, relative to the dog's predatory instincts, are the key to producing very difficult yet consistent behaviors, and in most cases, do not involve operant, classical, or any other kind of conditioning.[citation needed] While evolutionary processes shaped these fix action patterns, the patterns themselves remained stable long enough to be shaped by the long time span necessary for evolution because of their survival function (i.e., operant conditioning).

According to the laws of operant conditioning, any behavior that is consistently rewarded, every single time, will extinguish at a faster rate while intermittently reinforcing behavior leads to more stable rates of behavior that are relatively more resistant to extinction. Thus, in detection dogs, any correct behavior of indicating a "find," must always be rewarded with a tug toy or a ball throw early on for initial acquisition of the behavior. Thereafter, fading procedures, in which the rate of reinforcement is "thinned" (not every response is reinforced)are introduced, switching the dog to an intermittent schedule of reinforcement, which is more resistant to instances of non-reinforcement.

Nevertheless, some trainers are now using the prey drive to train pet dogs and find that they get far better results in the dogs' responses to training than when they only use the principles of operant conditioning[citation needed] which, according to Skinner and his students Keller and Marian Breland (who invented clicker training), break down when strong instincts are at play.[4]

[edit] Criticisms

Thorndike's law of effect specifically requires that a behavior be followed by satisfying consequences for learning to occur. There are, however, cases in which learning can be shown to occur without good or bad effects following the behavior. For instance, a number of experiments examining the phenomenon of latent learning[5][6][7][8] showed that a rat needn't receive a satisfying reward (food, if hungry; water, if thirsty) in order to learn a maze; learning that becomes apparent immediately after the desired reward is introduced.

A different experiment, in humans, showed that punishing the correct behavior may actually cause it to be more frequently taken (i.e. stamp it in)[9]. Subjects are given a number of pairs of holes on a large board and required to learn which hole to poke a stylus through for each pair. If the subjects receive an electric shock for punching the correct hole, they learn which hole is correct more quickly than subjects who receive an electric shock for punching the incorrect hole.

[edit] Biological correlates of operant conditioning

The first scientific studies identifying neurons that responded in ways that suggested they encode for conditioned stimuli came from work by Rusty Richardson and Mahlon deLong.[10][11] They showed that nucleus basalis neurons, which release acetylcholine broadly throughout the cerebral cortex, are activated shortly after a conditioned stimulus, or after a primary reward if no conditioned stimulus exists. These neurons are equally active for positive and negative reinforcers, and have been demonstrated to cause plasticity in many cortical regions.[12]

Evidence also exists that dopamine is activated at similar times. The dopamine pathways encode positive reward only, not aversive reinforcement, and they project much more densely onto frontal cortex regions. Cholinergic projections, in contrast, are dense even in the posterior cortical regions like the primary visual cortex. A study of patients with Parkinson's disease, a condition attributed to the insufficient action of dopamine, further illustrates the role of dopamine in positive reinforcement.[13] It


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