AN EXAMPLE OF AN EXPERIMENTAL APPROACH

S. STERNBERG ANT THE RETURN OF DONDER (N A WAY)

ASSUME: OVERALL REACTION TIME (RT) IS AN ADDITIVE FUNCTION OF A SET OF MORE SIMPLE TASKS

CONSIDER THE FOLLOWING TASK:
PRESENT DIGIT(S) TO REMEMBER (MEMORY SET) , THEN PRESENT A DIGIT (THE "PROBE") . TASK: DECIDE WHETHER OR NOT THE PROBE WAS ONE OF THE ITEMS IN THE MEMORY SET

ONE CAN CONCEPTUALIZE THE PRIMITIVE SUB-TASKS AS:
e.g., RT= rt 1 (ENCODING OF PROBE) + rt 2 (SCANNING THE MEMORY SET FROM MEMORY) + rt 3 (RESPONSE SELECTION: YES OR NO) + rt 4 (RESPONSE GENERATION)

STERNBERG'S MODIFICATION IS THAT HE MANIPULATED ONLY ONE OF THE STAGES, AND KEPT ALL ELSE CONSTANT THUS HE DID NOT HAVE TO RELY ON SUBTRACTIVE LOGIC



MEMORY SET PROBE RESPONSE
 
MEMORY SET

(MANIPULATE 1->5 DIGITS ON ANY ONE TRIAL)

PROBE

TIMER STARTS

RESPONSE

TIMER STOPS

NOTE SOME OF THE QUESTIONS THAT HE CAN ASK:

1. DOES MEMORY SEARCH PROCEED IN SERIAL OR IN PARALLEL

2. IS SEARCH EXHAUSTIVE OR SELF-TERMINATING
QUESTION: WHEN IS SEARCH DEFINITELY EXHAUSTIVE?

SO: EXAMINE THE SLOPES PRODUCED BY:______________

 3. ARE EFFECTS INDEPENDENT OR INTERACTIVE (ADDITIVE FACTORS LOGIC: SIMILAR TO THE LOGIC OF AN INTERACTION IN STATISTICS)

LOGIC: IF MANIPULATION IMPACTS ONLY ONE STAGE THEN SHOULD GET ADDITIVE EFFECTS, BUT IF IMPACTS MORE THATN ONE STAGE THEN SHOULD GET INTERACTIVE EFFECTS

CONSIDER WHAT HAPPENS IF ONE MAKES IT MORE DIFFICULT TO ENCODE THE PROBE (MANIPULATE)



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