People diagnosed with obsessive-compulsive disorder often have trouble recalling specific personal memories, a cognitive characteristic that appears to exacerbate the severity of their symptoms. New research shows that this memory pattern is associated with deficits in mental flexibility and working memory, suggesting it could be a new target for psychotherapy. The study was published in the journal Behavior Research and Therapy.
Autobiographical memory allows people to mentally go back in time and recall detailed past experiences. Specific memories usually involve events that happened on a specific day and in a specific location. People who experience memories that are too general instead search for broader, less detailed summaries of events.
For example, a specific memory might be remembering a particular dinner you had with a friend last Friday night. All-too-common memories include frequent dinners with friends on the weekends. This tendency to recall categorical rather than moment-specific information is a cognitive characteristic recognized in several mental health conditions.
Obsessive-compulsive disorder is an often debilitating mental health condition characterized by intrusive, unwanted thoughts and repetitive behaviors. People living with this condition often struggle with a variety of mental tasks collectively known as executive functions. Executive function functions as the brain’s management system, directing focus, keeping information in mind, and stopping impulsive behavior.
Previous research into how excessive memory affects people with obsessive-compulsive disorder has yielded mixed results. Some early studies suggest that the memory deficits observed in these patients are actually the result of a combination of symptoms of depression and anxiety. How executive function relates to memory recall in this particular population remained a mystery.
Researchers Lil Qian and colleagues at China’s Central South University designed a study to resolve these ambiguities. The research team wanted to see if excessive memory existed independently of mood disorders in people with obsessive-compulsive disorder. They also aimed to uncover how specific components of executive function are related to these memory patterns and overall symptom severity.
To investigate these relationships, researchers recruited 112 patients diagnosed with obsessive-compulsive disorder and 101 healthy subjects from the local community. Patients underwent a diagnostic interview to confirm their condition and rule out other severe mental illnesses such as major depressive disorder or schizophrenia. A total of approximately 200 participant groups completed a battery of computerized behavioral tests and clinical assessments.
The research team used a specialized autobiographical memory test to measure how well participants could recall specific events. In this test, individuals were presented with a series of positive, negative, and neutral cue words. Participants had 1 minute per word to describe a specific personal event related to the prompt. Trained raters later scored the responses based on how specific or broad the recollections were.
The researchers also assessed three separate types of executive function using different behavioral tasks. They used a memory order challenge to measure working memory, which requires retaining and updating information over short periods of time. During this test, participants had to monitor a series of digits and identify the point in time when the current digit matched the digit presented a few steps earlier.
To measure cognitive flexibility, the team used a task-switching game. Cognitive flexibility is the mental agility required to shift attention between different rules and concepts. Participants looked at numbers inside geometric shapes and had to judge the numbers differently depending on the surrounding shapes.
Finally, the researchers assessed inhibitory control using a stop-signal task. Inhibitory control is the ability to inhibit a behavior that has already been initiated. Participants pressed designated buttons in response to specific letters, but were instructed to suppress their physical response if the letters on the screen suddenly changed color.
The researchers also recorded the severity of symptoms in the obsessive-compulsive disorder group. They used a standardized clinical questionnaire that ranks the intensity of invasive thoughts and compulsive behaviors.
The study revealed significant differences in how the groups recalled their past. Obsessive-compulsive disorder patients showed much higher rates of overmemory when presented with positive and negative cue words. They recalled broad categories of emotional events rather than specific, fixed moments.
This pattern did not hold for neutral cue words. Both the clinical and healthy control groups recalled similar levels of specific details when the prompts lacked emotional stimulation.
Researchers theorize that this response to emotional cues is related to patients’ chronic cognitive conditions. Intrusive negative thoughts can activate persistent negative mental frameworks. This framework takes over the retrieval process when a negative word appears, causing a rumination loop rather than a specific memory search.
A reduced ability to recall specific positive memories may be due to a mismatch in emotional states. Positive prompts conflict with the patient’s internal mood because the patient often experiences persistent distress. This emotional mismatch makes it difficult to access specific happy memories and prompts the brain to give general answers instead.
The researchers used a statistical model to account for participants’ baseline levels of depression and anxiety. Even after controlling for these mood factors, the differences in memory performance between the groups remained significant. This indicates that excessive memory properties are directly linked to the pathology of obsessive-compulsive disorder.
By analyzing executive function scores, the team revealed how mental management skills are related to memory recall. Cognitive flexibility was found to be the strongest predictor of general memory overload among clinical groups. The patients who had the most trouble adjusting to the change in rules during the task-switching game also had the most trouble recalling specific memories.
Deficits in working memory also predicted higher rates of deficits in general memory. The ability to monitor and update information appears to help the mind filter a wide range of experiences to find specific events. Of note, scores on the stop signal task did not yield a statistically significant association with memory recall.
In this context, the specific ability to inhibit behavioral responses does not seem to determine the specificity of memory. Memory problems appear to be rooted in a failure to strategically construct and shift memory retrieval, rather than a failure to block intrusive information.
The research team then looked at how these cognitive challenges related to patients’ daily struggles. They found that a higher propensity for general memory overload predicted worse overall symptom severity. Patients who recalled nonspecific details about their past experienced the most intense obsessions and compulsions.
A moderate relationship was found between cognitive flexibility, memory, and symptom severity. The association between excessive memory and symptom worsening was particularly peaked among patients with the least cognitive flexibility. Mental rigidity appears to exacerbate the negative effects of memory impairment.
The authors noted several limitations in the study methodology. This study utilized a cross-sectional design that collected data at a single time point. This approach precludes definitive conclusions about causation.
It is impossible to say whether cognitive impairment causes severe symptoms or whether severe symptoms reduce cognitive ability over time. Following patients over time may help establish the precise direction of these psychological relationships.
The researchers also noted that the measure of inhibitory control has limitations. Stop-signal tasks only measure behavioral inhibition and miss internal cognitive mechanisms. A broader battery of tests could reveal different connections between memory and the ability to suppress certain thoughts.
Because this study relies entirely on behavioral game performance, the underlying brain biology remains unknown. Subsequent research could use brain imaging techniques to observe the neural activity that occurs while patients try to recall personal events. Understanding these physiological mechanisms may improve targeted psychological treatments to reduce the functional burden of severe obsessive-compulsive disorder.
The study, “General autobiographical memory in obsessive-compulsive disorder: Different roles of executive function subcomponents and influence on symptom severity,” was authored by Liru Qian, Huihui Yang, Guojuan Jiao, Meiqian Tang, Xiaoshuang Gu, Mingtian Zhong, Ming Cheng, and Jinyao Yi.
