A new study published in the British Journal of Psychology has found that individuals who report symptoms of attention-deficit/hyperactivity disorder tend to experience more involuntary memories in everyday life than those without such symptoms. These spontaneous recollections were also rated as less positive and more repetitive.
The researchers set out to explore whether spontaneous remembering—unintended recollections of personal experiences—might be more frequent among people with ADHD traits. While past research has established a connection between ADHD and increased mind wandering, it was unclear whether this tendency also extended to involuntary memories.
Earlier studies had produced mixed results. Some naturalistic studies hinted at a link between distractibility and spontaneous remembering, while others using laboratory-based measures found no such association. The authors of the current study suspected that traditional lab tasks might fail to detect real-life differences and designed two complementary studies to investigate.
In the first study, 453 undergraduate participants completed the Barkley Adult ADHD Rating Scale (BAARS-IV), a validated questionnaire used to identify symptoms of ADHD. Based on their scores, participants were grouped into those who scored within the ADHD range and those who did not. All participants then took part in a vigilance task, which was designed to measure spontaneous thoughts and memories in a controlled setting.
During this task, participants viewed a sequence of slides and were asked to report any unplanned memories or thoughts they experienced. After the task, they completed a separate questionnaire asking them to estimate how often they experienced involuntary memories in their daily lives, how emotionally positive or negative these memories tended to be, and how often the same memories repeated.
The results of this first study showed no difference in the number of spontaneous memories reported during the laboratory task between those with ADHD symptoms and those without. However, the questionnaire responses painted a different picture. Participants who scored in the ADHD range estimated that they experienced significantly more involuntary memories in their daily lives compared to the other groups. They also described these memories as being less positive and more repetitive. These findings suggest that while laboratory settings may not always detect variations in spontaneous memory experiences, self-reported everyday experiences can reveal meaningful differences.
To build on these findings, the researchers conducted a second study using a more naturalistic method. A new sample of 116 participants, including both students and community members, also completed the BAARS-IV. They were then asked to carry a pocket-sized diary for 48 hours and record every involuntary memory they experienced during that time. For each memory, they noted the time, their age in the memory, and rated its emotional tone, emotional impact, how often the memory had occurred before, and how focused their attention was at the time.
This diary-based study provided additional support for the researchers’ expectations. Participants with ADHD-range scores recorded significantly more involuntary memories over the 48-hour period than those in the non-ADHD range. On average, they reported nearly twice as many memories. As in the first study, they also rated their memories as less emotionally positive. However, unlike the questionnaire results, there were no significant group differences in how repetitive the memories were or in attention levels reported at the time the memories occurred.
Together, these findings indicate that people with ADHD symptoms may experience more frequent spontaneous memories than others, particularly in their day-to-day lives. The difference was not apparent during a controlled laboratory task, which the researchers believe may not reflect real-world attention dynamics. In fact, they propose that the vigilance task, which includes meaningful word phrases, may actually help participants with ADHD maintain their focus, suppressing spontaneous memories that would otherwise occur in less structured settings. Alternatively, the task may have artificially elevated the rate of spontaneous memories in non-ADHD participants, masking any differences between groups.
The diary method, in contrast, offered a more natural glimpse into how often these memories arise in ordinary circumstances. Since participants were recording experiences in real time as they went about their daily lives, this method may better reflect genuine cognitive differences between people with and without ADHD symptoms.
The researchers acknowledged several limitations in their work. First, the participants were not formally diagnosed with ADHD, but rather scored in the ADHD range on a self-report scale. While this method is commonly used in psychological research, future studies with clinically diagnosed samples would help confirm the findings.
The study also relied on self-report measures, which can be vulnerable to inaccuracies. For instance, people with ADHD may over- or underestimate how often they experience repetitive memories. Although the diary method helps address some of these concerns, it too has limitations. Participants may have forgotten to record some memories, especially if they occurred frequently, which could lead to underreporting.
Despite these challenges, the study adds to a growing body of evidence suggesting that people with ADHD symptoms tend to experience more spontaneous cognitive events, including not only future-oriented mind wandering but also unintentional recollections of past experiences. These findings could help researchers better understand how attention and memory interact in people with attentional difficulties.
The authors suggest that future research could use longer diary recording periods to capture patterns that might not appear over just two days. They also recommend further investigation into why these differences arise. While one theory holds that people with ADHD have weaker mechanisms for filtering out irrelevant memories, the evidence for this remains inconclusive. More research is needed to clarify what drives these differences in spontaneous remembering and how they affect daily functioning.
The study, “Involuntary remembering and ADHD: Do individuals with ADHD symptoms experience high volumes of involuntary memories in everyday life?“, was authored by John H. Mace, Assegedetch HaileMariam, Jian Zhu, and Natalie Howell
