Final answer:
There is increased activity in the right lateral prefrontal cortex when individuals work on ill-defined anagrams compared to well-defined anagrams, which correlates with the increased cognitive demand for problem-solving.
Step-by-step explanation:
The activity in the right lateral prefrontal cortex for ill-defined anagrams compared to well-defined anagrams is increased. When an individual is presented with an ill-defined anagram, the cognitive demand to solve the puzzle is higher, requiring more creative problem-solving strategies and possibly dealing with ambiguity. The right lateral prefrontal cortex is implicated in processes related to problem-solving and cognitive control.
When presented with a well-defined anagram, which has clearer constraints and possibly easier to deduce solutions, the cognitive load is potentially lower. Thus, one would expect a decrease in neuronal activity in those areas responsible for problem-solving when the problem is easier to define and solve.