ch4
TRANSCRIPT
Automatic processing and action slips
WITH PRACTICE, WE CAN DO ONE, TWO, OR MORE TASKS AT THE SAME TIME .
AND THE DEMAND ON OUR ATTENTION PROCESSES BECOMES MUCH LOWER.
Automatic Processing
Feature of automatic processing
Faster than processes with conscious control.Effortless, for its no need to think about it.Little or no awareness to it.Unavoidable since it’s triggered by external
or internal stimuli.
Stroop effect
A typical way to show the automatic processing.
Shiffrin and Schneider’s theory
Two distinct way dealing with task Controlled processes Automatic processes
Evaluation
• Eysenck and Keane(1995) criticized that this theory is descriptive rather than explanatory.
• Neuman(1984) claims that controlled and automatic processes merely represent different level of control.
• Some alternative explanation is that practice changes the nature of the processes. – Cheng(1985) explain it as restructuring rather than
automaticity.
Norman and shallice’s theory
Fully automatic processingPartially automatic processingDeliberate controll
The instance theory
Logan(1988) proposed.Two ways participants can decide on how to
response Use an algorithm Use memory retrieval
The future challenge
The change caused by practice are due to? Changes in memory retrieval Change in processing capacity Restructuring of processing A combination of factors
Action slips
生活中的例子
沒去注意所造成的 -- 把 shaving cream 用來刷牙疏忽所造成的 -- 要泡茶卻只把熱水倒入茶壺而沒有茶葉
研究 action slips 的方法
日記法 (Diary studies)實驗室法 (Laboratory studies)
日記法 (Diary studies)
讓受試者去記錄它們自己在生活中所犯的錯誤。
Reason (1979) 的研究
問 35 位受試者讓他們自己記錄兩周內所察覺action slips 的錯誤
結果
Reason 把這些 action slips 分為五個種類種類 (categories) 特性 百分比 (%)
Storage failures Actions are forgotten or recalled incorrectly
40%
Test failures A failure to monitor intended sequences and cause switch to another action
20%
Sub-routine failures Errors involve addition, omission of one stage in a sequence
18%
Discrimination failures Failures to discriminate between two objects
11%
Programme assembly failures
Inappropriate combination of actions
5%
日記法的問題
只記錄人們可以察覺 (aware) 或是記得(remember) 的 action slips 。
-- 沒有辦法去檢查那些沒有被察覺到的 action slips的數量。
有些 Reagon 分成同一類的,有可能是不同種類的。
實驗室法 (Laboratory studies)
用實驗的操弄 (ex. misleading context) 引起受試者的 action slips
Reason (1992) 的實驗
要受試者快速回答一系列的問題,而這些問題的答案其英文發音的韻腳都是一樣的。
Q: What sound does a frog make?A: Croak Q: What do we call a funny story?A: Joke…Q: What do you call the white of an egg?A: ?
(85% 回答 yolk ,但 yolk 蛋黃。正確答案是albumen 蛋白。因為受試者受到前面答案的韻腳影響。 )
若只單獨問最後一個問題,則只有 5% 的人會回答成yolk( 錯的答案 ) 。
實驗室的 action slips 和真實生活中自然的 action slips 是有差距的。
實驗情境中,受試者都是動機強且想把作業 (task) 做好的 ; 但在真實生活情境裡, action slips 是自然而然發生的。
Theories of action slips
Reason’s theory
Sellen and Norman’s theory
Reason’s theory
Reason(1992) 認為行為是被兩種 mode 控制 :
Automatic mode
Open loop: An action is initiated but then is left to continue without feedback or supervision.
Conscious controlled mode
Closed loop: An action is started and then monitored. It has constant feedback.
Reason’s theory
Open loop (Automatic mode)
1. Fast2. Allow attention be used
to other tasks3. Inflexible4. Little or no feedbacks5. Leads to action slips
Closed loop(Conscious controlled mode)
1. Slow2. More efforts3. Action is monitored4. Responses are flexible5. Few mistakes
探討 Reason 的理論
Logan (1988) 認為 - 自動化處理 (automatic processing) 可以用記 憶提取 (memory retrieval) 來解釋。
- 第一個問題 : action slips 是處理的失敗,還是記憶的失敗 ?- 第二個問題 : “It is only automatic control of well-
practiced tasks that leads to action slips’ 太過於簡化了 。
- The nature of the tasks may influence the probability of mistakes.
ex. 泡茶 -action slips 易發生 跳傘運動的選手– action slips 不易發生 , 任何的錯誤都是危及性命的。
- 第三個問題 : Reason 的理論不能解釋為什麼 action slips 在
closed loop (conscious controlled mode) 也會發生。
Sellen and Norman’s theory
Sellen and Norman (1992) -actions are governed by schemas - schemas are organised in hierarchies
Schemas
The highest level Lower-level schemas
Parent schemas Child schemasConcerned with overall intentions
Correspond to individual actions needed to accomplish parent schemas
泡咖啡 把水壺打開 , 把咖啡放到茶杯裡 ..
Activation level of schemas
有兩種因子決定 : (1) intention (ex. 我要一杯咖啡 ) (2) environmental stimuli (ex. 當水煮開了 , 我們要把熱水倒 入杯子了 )
Action slips 的發生
會在 (1) parent schemas (2) child schmas 發生
Action slips 發生的形式
Errors in the formation of an intention. ( 要去商店卻去了實驗室 )Activation of the wrong child schema.( 把咖啡倒入 teapot 而不是 cup)
Action slips 發生的形式
A child schema is not activated. ( 忘記把茶壺的開關打開 )Faulty triggering of active schemas so that an
action is taken over by the wrong parent schema.
( 要瀏覽心理學的網頁,卻突然發現正在流覽某個購物網站 )
探討 Sellen and Norman 的理論
沒辦法解釋 action slips 為什麼會發生在deliberate control 的時候。
都假設 action slips 發生在自動處理處的時候。
整理
Reason’s theory Sellen and Norman’s theory
假設 Action slips 發生在自動化處理
假設 Action slips 發生在自動化處理
Closed loop and open loop
Parent schemas and child schemas
無法解釋 action slips 為何會發生在 closed loop
無法解釋 action slips 為何會發生在 deliberate control 的時候
Applying theories of action slipsReason (1979)
Pilot error involved action slips rather than an error of judgment during crew was dealing with a genuine emergency which captured the pilots’ attention
Reason (1990) Accidents reveal a mixture of individual mistakes
Reason (1990) “Human Error”-- GEMS Skill-based slips: storage failures Rule-based mistakes: Knowledge-based mistakes: overconfident
Examples of accident
Oyster Creek power station 1979 Switched off 4 valves (A, E, B, C) instead 2 (A, E)
Chernobyl nuclear power station 1986 Reactor power reduced to less than 10% that prohibited safety procedures operation ( < 20%) Further safety procedure violated Explosion within the core Blew off 1000 ton concrete cap
Reason (1990)Build-in system response to mitigate the error
Warnings Locking Do nothing Self-correction Dialogue teaching
Build-in procedures or mechanisms for people detect them
Robertson (1997)SART – sustained attention to response test
Digit from 1 to 9 presented at regular intervals Press a button after each number except number 3 occurs
Reaction times immediately preceding the incorrect responses became significantly shorter (suggesting
that people were not concentrating on task)Correlation between scores on SART and action slips
in both brain-injured and healthy control people Improving performance on attention can aid recovery Train people to improve their performance on attentional tasks
Summary Shiffrin & Schnerder
Controlled processing & automatic processing
Norman & Shallice Three levels of processing
Logan Automatic processing explained in terms of memory retrieval
Reason Action slips are grouped into five categories
Sellen & Norman Actions are guide by a hierarchy of schemas
None explains why errors occur when using cared control