Answer to Question 1
Answer: In a delayed response task, an animal looks at a central location while a different spatial location is cued. After a delay, the animal is given a signal to look at the cued location. The assumption is that the cued location must be held in working memory. Single-cell recordings have shown in the activity of neurons in the dorsolateral regions of the prefrontal cortex. Some cells increased activity during the cue while others increased activity during the delay when no perceptual information was presented. Further, cell activation corresponded to particular locations on the display.
Answer to Question 2
Answer: The basic idea behind weight-based memories is that the strength or weight of memory representations undergoes a relatively permanent strengthening or weakening reflecting an underlying structural change of neural pathways.