A new study published in the Journal of Psychiatric Research sheds light on how cognitive-behavioral therapy (CBT) for hoarding disorder influences brain activity, reflecting reductions in maladaptive beliefs about possessions. Researchers found that adults undergoing group CBT showed increased brain activity in regions associated with decision-making and emotional processing when discarding items, aligning with improvements in their beliefs about the necessity of keeping possessions.
Hoarding disorder involves extreme difficulty discarding possessions, leading to clutter that disrupts daily life and causes significant distress. While CBT is a recognized treatment, its effectiveness varies, with many individuals showing improvement but not complete resolution of symptoms. To enhance treatment outcomes, researchers need a deeper understanding of how therapy fosters these changes.
Past research highlighted the role of maladaptive beliefs—such as excessive emotional attachment to objects or fear of losing control over possessions—in maintaining hoarding behaviors. Reducing these beliefs during CBT has been associated with symptom improvement. However, less is known about how these belief changes correspond to neural activity, particularly in regions activated during decisions about discarding items.
“There’s a lot we don’t yet know about hoarding disorder, which is estimated to affect 2–6% of the population and is more common among older adults,” said study author Kelly Knowles, a clinical psychologist at the Institute of Living at Hartford Hospital. “We know that cognitive-behavioral therapy for hoarding disorder leads to symptom improvement for most patients, which is great news, but not everyone experiences clinically significant improvement, so we have more work to do.”
“In particular, we’ve noticed that the individuals we work with in hoarding treatment seem to think differently than the average older adult – they tend to endorse beliefs such as ‘I am responsible for the well-being of my possessions’ and ‘I could not tolerate it if I had to throw this item away.’ Our study allowed us to look more closely at specific brain changes from pre-treatment to post-treatment and explore associations between brain changes and these beliefs.”
The study analyzed data from 58 adults diagnosed with hoarding disorder who participated in group CBT. Participants underwent functional magnetic resonance imaging (fMRI) before and after therapy to measure brain activity during a simulated discarding task. In this task, participants viewed images of items and decided whether to “keep” or “discard” them, imagining the process as part of “spring cleaning.”
The researchers focused on brain areas previously associated with hoarding disorder, including the insula and anterior cingulate cortex, which are involved in processing emotional significance and decision-making. Changes in participants’ beliefs about possessions were measured using a validated questionnaire. These beliefs were grouped into categories such as emotional attachment, memory concerns, control over possessions, and feelings of responsibility toward objects.
Before therapy, participants with stronger maladaptive beliefs about possessions showed heightened activity in brain regions such as the left middle insula and the left anterior cingulate cortex when deciding to discard items. These findings align with previous research suggesting that these areas are hyperactive in individuals with hoarding disorder, reflecting the heightened emotional and cognitive burden of discarding possessions.
After therapy, participants reported significant reductions in maladaptive beliefs, such as feeling overly responsible for their belongings or fearing that discarding items would lead to unbearable distress. These belief changes were linked to increased activity in regions associated with decision-making and processing emotional salience, including the right anterior ventral insula, left middle frontal gyrus, and bilateral inferior temporal lobe.
Interestingly, brain activity in visuospatial areas also increased, suggesting that participants were better able to visually evaluate items during the discarding task. This shift may indicate a more balanced approach to decision-making, with less emotional interference.
The findings suggest that therapy not only reduces problematic beliefs but also reshapes the brain’s response to emotionally charged decisions about possessions. For individuals with hoarding disorder, discarding possessions may feel “risky,” but therapy appears to help them reinterpret these decisions as less threatening, supported by changes in brain activity.
“The average person probably has a relative or family friend who has hoarding symptoms,” Knowles told PsyPost. “People should know that treatment for hoarding disorder—cognitive-behavioral therapy—is available and effective, though we still have more work to do in the scientific community to improve treatment.”
“The good news is that the beliefs that maintain hoarding disorder, such as excessive emotional attachment to objects, do change over the course of CBT treatment. These changes are also associated with changes in brain activity when patients are discarding their possessions.”
The researchers controlled for variables such as overall emotional distress and psychiatric medication use to isolate the effects of therapy on hoarding-specific beliefs and brain activity. But as with all studies, there are some caveats.
While it identified significant changes in neural activity, the results need replication in larger and more diverse samples to confirm the associations between belief changes and brain activity. Future research could also explore how these neural changes relate to long-term treatment outcomes and whether they can predict who will respond best to therapy.
“I always give the caveat that while neuroimaging (fMRI) research is exciting, there are still a lot of unknowns – just because our study found changes in brain activity during a laboratory task does not necessarily mean that these changes are stable, enduring, or are the reason behind clinical improvement,” Knowles explained.
“As I’m sure your readers have heard, ‘correlation is not causation’ – we know that changes in brain activity during a specific task are associated with cognitive changes, but we don’t know for sure that cognitive change is causing brain changes or that brain changes are causing symptom improvement.”
“There’s still so much we don’t know about how beliefs are represented in the brain. The story is never as simple as ‘this part does this thing, and doing this treatment fixes brain functioning.’ That’s what makes it such an exciting area to explore in future research.”
The study, “Changes in hoarding-related beliefs and associated neural changes during a simulated discarding task after cognitive behavioral treatment for hoarding disorder,” was authored by Kelly A. Knowles, Michael C. Stevens, Hannah C. Levy, and David F. Tolin.
