Drawing improves memory in patients with hippocampal damage.

The hippocampus plays a critical role in the formation of declarative memories, and hippocampal damage leads to significant impairments in new memory formation. Drawing can serve as a form of multi-modal encoding that improves declarative memory performance relative to other multimodal encoding strategies such as writing. We examined whether, and to what extent, patients with hippocampal damage could benefit from the mnemonic strategy of drawing. Three patients with focal hippocampal damage, and one patient with both hippocampal and cortical lesions, in addition to 22 age-, sex-, and education-matched controls, were shown a list of words one at a time during encoding and instructed to either draw a picture or repeatedly write each word for 40 s. Following a brief filled delay, free recall and recognition memory for words from both encoding trial types were assessed. Controls showed enhanced recall and recognition memory for words drawn versus those that were written, an effect that was even more pronounced in patients with focal hippocampal damage. By contrast, the patient with both hippocampal and cortical lesions showed no drawing-mediated boost in either recall or recognition memory. These findings demonstrate that drawing is an effective encoding strategy, likely accruing from the engagement of extra-hippocampal processes including the integration of cortical-based motor, visual, and semantic processing, enabling more elaborative encoding.

Brain regions supporting retrieval of words drawn at encoding: fMRI evidence for multimodal reactivation.

Memory for words that are drawn or sketched by the participant, rather than written, during encoding is typically superior. While this drawing benefit has been reliably demonstrated in recent years, there has yet to be an investigation of its neural basis. Here, we asked participants to either create drawings, repeatedly write, or list physical characteristics depicting each target word during encoding. Participants then completed a recognition memory test for target words while undergoing functional magnetic resonance imaging (fMRI). Behavioural results showed memory was significantly higher for words drawn than written, replicating the typical drawing effect. Memory for words whose physical characteristics were listed at encoding was also higher than for those written repeatedly, but lower than for those drawn. Voxel-wise analyses of fMRI data revealed two distributed sets of brain regions more active for items drawn relative to written, the left angular gyrus (BA 39) and bilateral frontal (BA 10) regions, suggesting integration and self-referential processing during retrieval of drawn words. Brain-behaviour correlation analyses showed that the size of one's memory benefit for words drawn relative to written at encoding was positively correlated with activation in brain regions linked to visual representation and imagery (BA 17 and cuneus) and motor planning (premotor and supplementary motor areas; BA 6). This study suggests that drawing benefits memory by coactivating multiple sensory traces. Target words drawn during encoding are subsequently remembered by re-engaging visual, motoric, and semantic representations.

The drawing effect: Evidence for costs and benefits using pure and mixed lists.

Drawing a referent of a to-be-remembered word often results in better recognition and recall of this word relative to a control task in which the word is written, a pattern dubbed the drawing effect. Although this effect is not always found in pure lists, we report three experiments in which the drawing effect emerged in both pure- and mixed-lists on recognition and recall tests, though the effect was larger in mixed lists. Our experiments then compared drawing effects on memory between pure- and mixed-list contexts to determine whether the larger mixed-list drawing effect reflected a benefit to draw items, a cost to write items, or a combination. In delayed recognition and free-recall tests, a mixed-list benefit emerged for draw items in which memory for mixed-list draw items was greater than pure-list draw items. This mixed-list drawing benefit was accompanied by a mixed-list writing cost compared to pure-list write items, indicating that the mixed-list drawing effect does not operate cost-free. Our findings of a pure-list drawing effect are consistent with a memory strength account, however, the larger drawing effect in mixed lists suggest that participants may also deploy a distinctiveness heuristic to aid retrieval of drawn items.

Drawing and memory: Using visual production to alleviate concreteness effects.

Countless experiments have been devoted to understanding techniques through which memory might be improved. Many strategies uncovered in the literature are thought to act via the integration of contextual information from multiple distinct codes. However, the mnemonic benefits of these strategies often do not remain when there is no clear link between a word and its multisensory referent (e.g., in abstract words). To test the importance of this link, we asked participants to encode target words (ranging from concrete to abstract) either by drawing them, an encoding strategy recently proven to be reliable in improving memory, or writing them. Drawing provides a compelling test case because while other strategies (e.g., production, generation) shift focus to existing aspects of to-be-remembered information, drawing may forge a link with novel multisensory information, circumventing shortcomings of other memory techniques. Results indicated that while drawing's benefit was slightly larger for concrete stimuli, the effect was present across the spectrum from abstract to concrete. These findings demonstrate that even for highly abstract concepts without a clear link to a visual referent, memory is reliably improved through drawing. An exploratory analysis using a deep convolutional neural network also provided preliminary evidence that in abstract words, drawings that were most distinctive were more likely to be remembered, whereas concrete items benefited from prototypicality. Together, these results indicate that while the advantageous effects of drawing exist across all levels of concreteness, the memory benefit is larger when words are concrete, suggesting a tight coupling between the drawing benefit and visual code.