Dissociation and double dissociations

Neuropsychologists typically try to design studies that provide evidence of the differential performance of brain damaged and control subjects because such studies can inform structure function relationships. Consider the following example: The right frontal lobe is thought to be important for memorising designs. To test this hypothesis, a researcher assesses memory for designs (MemD) and memory for words (memW) in group of people with known right frontal damage and a second group of non brain damaged controls