Anxiety disorder research in mice

Neuroscientists from the University of Texas recently discovered which nerve cells in the brain of a mouse are responsible for anxious memories. The research offers new insights into how an anxiety disorder such as OCD arises and how anxious memories are activated in the brain.

Almost one in five adults in the Netherlands ever suffers from an anxiety disorder. This is the conclusion of a study commissioned by the Ministry of Health, Welfare and Sport. People with an anxiety disorder associate an anxious memory of a certain odor or a noise that happened to be present during the traumatic experience. When the sound is heard again later, the fearful memory returns. In psychology they call this link a memory trail. According to psychologist Joke Baas (Utrecht University), the memory trail for fearful memories is so strong that it continues to determine behavior.

New memory track

During therapy they try to make a new memory track. In this way the association between the accidental sound and the fearful memory is disconnected. This is called extinction. For example, someone who listened to certain music during an accident or other traumatic event will be able to listen to that music again after therapy without feeling fear. The extinction track or the extinction track has then gained the upper hand. Because an original fearful memory trail does not disappear, but several traces co-exist, the fear can suddenly come back years after therapy. What is important is to make the quenching trail stronger.

Switch

Neuroscientist Michael Drew has now discovered that the extinction cells switch between different memory tracks. These cells are located in the hippocampus. This is the area in the brain where fear is remembered. The researchers applied a technique to live mice in which the extinction cells in mice could be switched on or off with blue light. Every time the researchers activated the extinction cells, the mice suppressed the acquired fearful memories. If the researchers switched off the extinction cells, the fearful memories returned. In this way, it has been clearly demonstrated that the extinction cells play a role in switching between memory tracks, according to psychologist Baas.

Source: Volkskrant 2-4-2019