This theory implies that there are qualitative differences between the ways words and pictures are processed during memory.įrom an evolutionary perspective, the ability to remember various aspects of one’s visual environment must be vital for survival, so it is not surprising that memory for pictorial material is particularly well developed. One theory of the mechanism underlying superior picture memory is that pictures automatically engage multiple representations and associations with other knowledge about the world, thus encouraging a more elaborate encoding than occurs with words ( 2, 5, 7).

This levels effect is greater for words than for pictures because of superior picture memory even after shallow or nonsemantic encoding ( 6). One such manipulation is the levels of processing effect, which is the advantage for later retrieval of more elaborate or semantic processing of stimuli during encoding ( 4, 5). In addition, various manipulations that affect memory performance do so differentially for pictures and words. This excellent memory for pictures consistently exceeds our ability to remember words ( 2, 3). It was shown several decades ago that people can remember more than 2,000 pictures with at least 90% accuracy in recognition tests over a period of several days, even with short presentation times during learning ( 1). Humans have a remarkable ability to remember pictures. Thus, superior overall memory for pictures may be mediated by more effective and automatic engagement of areas important for visual memory, including medial temporal cortex, whereas the mechanisms underlying specific encoding strategies appear to operate similarly on pictures and words. Each encoding strategy was characterized by a distinctive activity pattern, but these patterns were largely the same for pictures and words. Encoding of pictures resulted in greater activity of bilateral visual and medial temporal cortices, compared with encoding words, whereas encoding of words was associated with increased activity in prefrontal and temporoparietal regions related to language function. Encoding was carried out by using three different strategies to explore possible interactions between material specificity and types of processing. To do this, we used positron emission tomography to map the brain regions active during encoding of words and pictures of objects. We examined the neural correlates of memory for pictures and words in the context of episodic memory encoding to determine material-specific differences in brain activity patterns. A striking characteristic of human memory is that pictures are remembered better than words.

Drawings of memory pictures