What does this mean?

In this study we had three main findings:

• Controlling memory retrieval following reminders (the scene cues), makes those memories less likely to draw attention: Previous studies have shown that information in our long-term memory can impact our attention. Here, we show that the link between memory and attention is not automatic. Rather, information from memory needs to be retrieved and held active in mind in order for that information to draw attention. Intentionally regulating memory retrieval reduces the influence of a memory on attention.
• Controlling memory retrieval affected how well participants remembered pairs in a later memory test: This drop in memory accuracy for suppressed and substituted scene-tool pairs was worse even relative to pairs that weren't presented during the memory control and search phase (the baseline pairs). This is interesting because it means that controlling a memory weakens it to a level over and above what we might expect from just passive forgetting (i.e., pairs that were forgotten because they weren't rehearsed). This suggests that the neural process by which we lose memories due to forgetting is different from the one by which we lose memories that are the target of retrieval suppression, or thought substitution!
• Memory is worse when retrieval control is successfully engaged: This indicates that memory control is not an all-or-none phenomenon. Different individuals may have differential ability to exert intentional control over retrieval. Furthermore, the same individual may achieve varying levels of success with retrieval control on a moment-to-moment basis (in this case, from one trial to the next), and graded levels of retrieval control seem to have a graded effect on memory.

What does this mean for PTSD and Depression?

Our results suggest that controlling retrieval makes the retrieved information less likely to draw attention, and may weaken the memory. It is possible that this may be an effective strategy in these mental health disorders to reduce the disruption caused by the retrieval of traumatic memories. However, this is very preliminary evidence. We need to conduct follow-up studies with emotional stimuli to examine if our results will translate to negative memories. Similarly, we need more data on such studies from patient populations to examine whether this is a viable treatment approach.