The stroop studies

1. The stroop studies Controlled Vs automatic processing

2. Experiment one CONTROL CONDITION • Time taken to read colour words printed in black ink • Eg. black, red, blue, green EXPERIMENTAL CONDITION • Time taken to identify the colour of the ink the words are printed in • Eg. Red, green, blue, purple

3. Experiment one – variables & hypothesis • IV – colour of ink used to print word (congruent or incongruent) • DV – time taken to name the colour of the ink • Hypothesis – that participants would take longer to identify the ink colour (incongruent list) than to read the black word list

4. Experiment two CONTROL CONDITION • Time taken to identify colour blocks • Eg. EXPERIMENTAL CONDITION • Time taken to identify the colour of the ink the words are printed in • Eg. Red, green, blue, purple

5. Experiment two – variables & hypothesis • IV – colour of ink used to print word (inconcruent) or block • DV – time taken to identify the colour of the ink used to print the blocks or words • Hypothesis – that participants would take longer to identify the colour of ink used to print incongruent words as compared to blocks of colour

6. Experiment three • Participants attempted each of the 4 previously listed conditions with one exception • Instead of colour blocks Stroop used symbols, in this conditions participants were to name the ink colour • Eg.

7. Results and conclusions • In all experiments participants took significantly longer to name an incongruent colour (conflicting task) than identify colour under any other condition • It seems that reading is an automatic response • To name the ink colour is a controlled process • Automatic processing takes precedence over controlled processing, we cant stop it even if we want to • Naming the ink colour requires attention and cognitive effort • Our automatic response to read interferes with our ability to name the colour of the ink

8. Research design • All 3 experiments used separate samples of participants • All 3 experiments used a repeated measures design where all participants did both conditions • All 3 experiments used counter balancing

9. Experimental Vs Control Groups Experimental Groups • Participants are exposed to the experimental condition (i.e. The IV is present – identify ink in incongruent words) Control Group • Participants who are exposed to the control condition (i.e. the IV is absent- read words in black ink) •  We compare the experimental group to the control group

10. Extraneous Variables Extraneous Variables – can effect DV • A random variable other than the independent variable that can cause change in the dependent variable and therefore effect the results of an experiment • e.g. Differences among participants - personal characteristics, ability, temperament, motivation etc. • When the effects of an extraneous/uncontrolled variable are confused, or confounded with those of the independent variable, then the extraneous variable has become a confounding variable • What else could effect naming of ink colour and reading other than the incongruence? – Eye Sight, colour blindness, literacy

11. Repeated Measures Design Repeated Measures Design • Each participant is involved in both the experimental and control conditions • This design controls or eliminates any effects that might be attributed to participant's personal characteristics, since they remain constant • Also known as the within participants design • Can suffer from the Order Effect - effect of practice and fatigue • Counterbalancing can help this

12. Repeated Measures Design

13. Research designs – Make all things equal…… except for the IV • All research designs attempt to ensure that the Experimental and Control groups are as similar as possible on all characteristics except for the IV • They aim to make the only difference between the groups whether they were exposed to the IV (experimental group) or not (control group)