Levels-of-processing Effect - Neural Evidence

Neural Evidence

Several brain imaging studies using positron emission tomography and functional magnetic resonance imaging techniques have shown that higher levels of processing correlate with more brain activity and activity in different parts of the brain than lower levels. For example, in a lexical analysis task, subjects showed activity in the left inferior prefrontal cortex only when identifying whether the word represented a living or nonliving object, and not when identifying whether or not the word contained an "a". Similarly, an auditory analysis task showed increased activation in the left inferior prefrontal cortex when subjects performed increasingly semantic word manipulations. Synaptic aspects of word recognition have been correlated with the left frontal operculum and the cortex lining the junction of the inferior frontal and inferior precentral sulcus. The self-reference effect also has neural correlates with a region of the medial prefrontal cortex, which was activated in an experiment where subjects analyzed the relevance of data to themselves. Specificity of processing is explained on a neurological basis by studies that show brain activity in the same location when a visual memory is encoded and retrieved, and lexical memory in a different location. Visual memory areas were mostly located within the bilateral extrastriate visual cortex.