fMRI Designs

1. Block

1.1. Task blocks

1.2. Additive response

1.3. Multiple scans per task block

1.4. "Spot the difference"

1.5. High statistical relevance

1.6. Problems

1.6.1. Sensitive to signal drift

1.6.2. Poor baseline choice

1.6.3. Repetition problems

1.6.3.1. Subject knowing what will happen

1.6.4. One condition per block

1.6.4.1. No randomization

2. Event related

2.1. Trial/rest/trial/rest

2.2. More real world testing

2.3. Low statistical relevance

2.3.1. One stimulus

2.3.2. Single BOLD change

3. Subtraction paradigm

3.1. Spot the differences shows what happens

3.2. Inference constraints

3.2.1. Reverse inference

3.2.1.1. Task A activates Z

3.2.1.1.1. New study

3.2.1.2. Process B activates Z

3.2.1.2.1. Old study

3.2.1.3. Z activation shows task A involves process B

3.2.1.4. WRONG

3.2.1.4.1. Suggested as a guide not a concluding tool

3.2.2. Forward inference

3.2.2.1. Corellational method

3.2.2.2. Can't prove hard links

3.2.2.2.1. Pavlov involved hippocampus

3.2.2.2.2. No hippocampus: still pavlov