1. Event-related potentials (ERPs) Jarrod Blinch motorbehaviour.wordpress.com May 31 st, 2011

2. Type of electrodes Non-polarised silver-chloride (Ag/AgCl) Tin Gold or platinum 2

3. How many trials? EEG 50 uV ERPs – 60 trials for large component (~10 uV, P300, RP/LRP) – 150 medium (~5 uV) – 400 small (~1-2 uV) 3

4. Overview Event-related potentials (ERPs) Advantages and disadvantages ERP components and waveform peaks Strategies to interpret ERP components Quantifying noise Components – Readiness potential (RP, LRP) – P300 (P3a, P3b) Fractionating information processing – Osman and Moore, 1993 (LRP) – Luck, 1998 (P3b) 4

5. Event-related potentials (ERPs) Averaging to generate ERPs Tiny effects Relying on previous ERPology Reliability – Low within-participant variability – High between-participant variability 5

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11. Advantages and disadvantages Advantages Continuous measure of processing Independent of a behavioural response Evoked or emitted potentials Noninvasive Temporal resolution Disadvantages Functional significance Tiny effects Spontaneous or induced potentials Spatial resolution Peaks versus components… Latency jitter… 11

12. Stimulus identification Response selection Response programming 12 Imperative stimulus Response initiation Reaction time

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14. ERP components and waveform peaks 14

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18. Strategies to interpret ERP components 1.Focus on a specific component 2.Use well-studied experimental manipulations 3.Focus on large components 4.Isolate components with difference waves 5.Focus on components that are easily isolated 6.Use component-independent experimental designs 7.Hijack useful components from other domains 18

19. Quantifying Noise 19

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22. Overview Event-related potentials (ERPs) Advantages and disadvantages ERP components and waveform peaks Strategies to interpret ERP components Quantifying noise Components – P300 (P3a, P3b) – Readiness potential (RP, LRP) Fractionating information processing – Osman and Moore, 1993 (LRP) – Luck, 1998 (P3b) 22

23. P300 23

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26. Readiness potential (RP) 26 Early RP Late RP MP

27. Lateralised readiness potential (LRP) 27

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29. Stimulus identification Response selection Response programming 29 Imperative stimulus Response initiation Reaction time P300 LRP

30. Psychological refractory period 30

31. 31 Bottleneck Stimulus onset asynchrony (SOA)

32. Osman & Moore, 1993 32 Stimulus identification Response selection Response programming LRP Stimulus identification Bottleneck Response selection Response programming Stimulus identification Response selection Bottleneck Response programming

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36. Luck, 1998 36 Stimulus identification Response selection Response programming P300 Stimulus identification and Bottleneck Response selection Response programming Stimulus identification Response selection and Bottleneck Response programming

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40. Event-related potentials (ERPs) Jarrod Blinch motorbehaviour.wordpress.com May 31 st, 2011