Can You Break the Mood-Memory Cycle?

Does it ever seem that the only thoughts that come to mind are negative? You only remember the painful and sorrowful experiences from your life. Someone reminds you of something happy, but you struggle to remember it. And remembering that happy experience may make you feel worse rather than better.

All of us have times when we’re sad and focused on negative thoughts and memories. Many of us will experience an episode of depression at some point in our lives. Depression is more than simply an emotional problem; something more substantial than simply feeling sad. Depression affects all aspects of existence—social interactions, work, eating, and sleeping. Of course depression also impacts memory and cognition.

Depression has two important effects on memory. The first effect is that depression leads to the mood dependent retrieval of negative personal memories. Emotion and memory can develop a reciprocal feedback loop: Your mood determines the memories that come to mind and the memories that come to mind influence your mood state. This can be wonderful when you’re happy—you remember pleasant autobiographical events which helps to keep you happy.

The problem occurs for people in a depressed mood state. In several studies researchers have documented mood dependent memory effects in depressed individuals (Bradley, Mogg, & Williams, 1995; Clark & Teasdale, 1982; Llyod & Lishman, 1975; Teasdale, 1983). People are asked to recall memories in response to neutral cues. Individuals who are depressed tend to recall more negative personal experiences than people who aren’t depressed. Even when looking only at depressed individuals, they recall more negative personal experiences at times of the day when feeling more negative than times when feeling less depressed (depressed mood varies within the day among individuals with depression). In depression, remembering creates a cycle that maintains the negative emotional state.

Although depressed individuals display mood dependent memory, the second impact of depression seems to be more powerful. Depressed individuals recall more overgeneral memories than individuals without depression (Kuyken & Dalgleish, 1995; Williams & Broadbent, 1986; Williams & Dritschel, 1988; Williams & Scott, 1988). In autobiographical memory research, people are asked to retrieve specific personal experiences—memories of single events that happened on a particular day. Although asked for specific memories, individuals often respond with more general responses. General memories can include repeated events—instead of describing what happened when I drove to work this morning, I may note that I drive to work every morning. General events also include extended events that occur over the course of more than a single day. General memories also includes self-knowledge. Individuals with depression experience more difficulty retrieving specific memories and instead report a higher percentage of general memory responses. Overgeneral memory predicts the course of depression as well. Depressed individuals who display a greater tendency to recall overgeneral memories are more likely to still be depressed in follow-up assessments months after an original measurement of depression and autobiographical memory (Raes et al., 2006; Sumner, Griffith, & Mineka, 2010).

In sum, individuals with depression have a greater tendency to retrieve negative autobiographical experiences and are often slow to retrieve memories, particularly happy memories. Depressed individuals also retrieve a greater percentage of overgeneral memories. Depression drives the retrieval of autobiographical memories in a direction different from that of non-depressed people. The retrieval of negative experiences and difficulties recalling specific memories may also maintain depression—an awful circular feedback loop maintains the state of depression.

Of course if memories maintain depression, perhaps memories can be used to break the cycle. Autobiographical memories might be used for mood regulation if you can successfully bring to mind happy memories when feeling sad. In an early investigation of mood regulation, Josephson, Singer, and Salovey (1996) placed people into either a sad or neutral mood and asked them to recall two autobiographical memories. Consistent with mood dependent memory, the first memories tended to be negative for people in a sad mood. But many people recalled a more positive second memory and this led to an improved mood state—recalling a positive memory repaired the negative mood the participants experienced. Unfortunately, people who were more depressed coming into the experiment were less likely to recall positive second memories and thus did not experience mood repair.

But what if individuals with depression are instructed to recall happy experiences? In a series of studies, Joorman and colleagues (Joorman & Siemer, 2004; Joorman, Siemer, & Gotlib, 2007) have explored whether both depressed and non-depressed individuals can use memories for mood regulation. Non-depressed individuals recall positive memories and use them for mood repair following the induction of negative moods. Depressed respondents, in contrast, experience more difficulty using memories for mood regulation. Even when depressed individuals recall positive memories, the memories may worsen rather than improve their sad moods (Joorman et al., 2007).

We all display mood dependent memories when we recall autobiographical memories. Some of us can use autobiographical memories for repairing our negative emotional states. For non-depressed individuals, remembering something happy will result in mood repair, leading to a more positive emotional state. But for people with depression, positive memories may not help. The advice to think happy thoughts and remember happy times may have divergent effects depending on the presence of depression.

Teaser image from Flickr free use with attribution: WorldIslandInfo.com