Missing Memories

Do you struggle to remember things about your life? If you’re having issues recollecting the details and events of your life and experiences, your problem may be the result of a sleep breathing disorder known as obstructive sleep apnea.

More than 936 million people worldwide live with obstructive sleep apnea (OSA), and many are untreated.

Those who haven’t been treated for the condition are at risk of developing chronic and potentially deadly illnesses, including high blood pressure, obesity, diabetes and heart problems.

Another condition that affects many individuals with OSA is memory loss, which contributes to depression.

A recent study conducted by RMIT University in Melbourne, Australia, and published in 2019 added to earlier studies investigating the link between depression and memory.

OSA is a serious health condition that develops when the airway becomes obstructed during sleep.

‘Airway obstruction is typically caused by the muscles of the throat relaxing or the tongue falling back to block the airway,’ said Dr. Sean Endsley of Legends Dental in Waco, Texas.

The study looked at autobiographical memory in individuals with untreated OSA and noted a significant difficulty recalling specific details about their lives.

The inability to recall these memories could lead to depression, frustration and sadness.

The reason for the inability to recall memories is that OSA impairs the brain’s ability to consolidate memories.

The researchers compared 44 adults living with untreated OSA to 44 individuals without the sleep breathing disorder, rating their ability to remember specific autobiographical memories from childhood, early adult life and recent years.

After their analysis, researchers found that people living with OSA had a greater rate of ‘overgeneral memory’ (52.3 percent) than control group participants (18.9 percent) and could not recall specifics about life events or situations. Overgeneral memory refers to difficulty retrieving specific autobiographical memories.

Researchers examined the ability to recall semantic memories, including facts and concepts from personal history, such as the name of a first pet or childhood friend, as well as episodic memory, which allows you to recall specific events, such as getting married or going off to college.

The study authors also found that while individuals living with OSA had problems remembering semantic memory, they didn’t have an episodic memory issue. The researchers believe this is due to the fragmented sleep patterns caused by the sleep breathing disorder. Previous research has shown a connection between good quality sleep and the brain’s ability to consolidate autobiographical semantic memory.

Based on information collected from both groups of participants, being older was also linked to having better overgeneral autobiographical memory recall, and higher levels of depression equated to having poor semantic memory.

The researchers also reviewed brain scans of people living with OSA. They found that those with the sleep breathing disorder often have a loss of gray matter in regions of the brain that overlap the parts of the brain where autobiographic memories are created.

Source: RMIT University. ‘Sleep apnea creates gaps in life memories: People with sleep apnea struggle to remember details of memories from their own lives, putting them at risk of depression.’ ScienceDaily, 31 January 2019.