Intrusive memories have the potential to trigger psychological distress. Several different mechanisms might explain their occurrence. Some of these mechanisms involve the effects of certain activities or mental states, such as Tetris or post-traumatic anxiety. Other mechanisms include future-directed expectations or region-related emotion. This article will discuss the effects of the various processes on intrusive memories.
Effects of Tetris on intrusions
Researchers have demonstrated that Tetris reduces intrusive memories after experiencing a traumatic event like a car crash. The researchers found that the video game reduced intrusive memories by 62%. They also showed that Tetris increases visuospatial processing.
Tetris' effect on intrusive memories relates to the game's difficulty and score. The higher a player's Tetris skill, the lower their intrusive memories. This may be because the better players had better visual-spatial abilities and therefore used more processing resources.
Effects of post-traumatic anxiety on intrusions
Recent studies have investigated the effect of post-traumatic anxiety on intrusions in patients with PTSD. The effectiveness of EMDR for reducing intrusive memories has been shown in several clinical settings. For example, women who experienced traumatic childbirth were given EMDR and reported having fewer intrusive memories than women who received usual care. Likewise, a PTSD study in inpatients with complex PTSD showed that EMDR reduced intrusive memories by 64% (both targeted and non-targeted) compared to a baseline.
In a meta-analysis of trauma film experiments, respondents who experienced a typical emotional response to the film were less likely to experience intrusions. This finding was confirmed by structural equation modelling, which found that the absence of intrusions was associated with lower trait anxiety and depression.
Effects of future-directed expectations on intrusions
The effects of future-directed expectations on intrusive memory have been studied in several ways. Some researchers have suggested that these expectations may affect the frequency and persistence of intrusive memories. However, others have shown that the effect of future-directed expectations is not as strong as previously thought.
One study found that a combination of past and future-directed expectations enhanced intrusive memories. In contrast, a similar study by Cheung, Garber, and Bryant (2015) found that acute stress increased intrusive memory scores. Specifically, higher cortisol was associated with higher intrusion scores. Furthermore, the stress induction occurred before the memory reactivation, which may have served as a new learning experience for participants.
Effects of region and emotion on intrusions
This study examined the role of emotion and region in maintaining intrusive memories. Participants were asked to record their memories of a stressful film that contained scenes that evoked negative emotions. The memories were recorded in digitized online diaries that participants accessed with a mobile phone. Intrusive memories arrive uninvited and can be expressed as verbal or sensory mental images. However, pure verbal thoughts are excluded from intrusion analyses.
This study showed that the posterior hippocampus and entorhinal cortex were significantly modulated in intrusion-related downregulation. The regions were also associated with affect suppression and the suppression of non-intrusive memories. The findings demonstrated that the association between region and emotion and intrusion suppression was statistically significant.