There are plenty of pharmaceutical drugs available to treat major depressive disorder (MDD). However, less than half of these patients remit within the first 3 months of treatment, and around 30% remain unresponsive. In this blog post, we talk about ketamine as a means to treat MDD by breaking down the scientific article, “Effects of Serial Ketamine Infusions on Corticolimbic Functional Connectivity in Major Depression.”
What happened in the study?
Chronic depression can lead to decreased connection between neurons over time. Additionally, the default mode network (DMN), which includes areas of the brain that are more active when someone is at rest or is daydreaming, is hyper-active in patients diagnosed with MDD. In fact, several resting-state networks (RSN) with features such as rumination, impaired attention, and cognitive control are all widely implicated in MDD.
This study aimed to determine the effects of ketamine on people with MDD through ketamine’s neuroplastic effects in reconnecting these neurons and regulating the RSNs responsible for emotion regulation, self-awareness, and social behavior.
Read our blog post Ketamine's Connection to Neurons to learn more about ketamine’s effects on neuron growth.
The study consisted of 44 patients with MDD and 50 healthy subjects. These healthy subjects did not receive ketamine while those with MDD were given several infusions of ketamine within a span of 2 to 2.5 weeks.
Results of the Study
The results indeed showed that ketamine’s neuroplastic effects have helped in increasing connectivity between the limbic regions of the brain and RSNs, which may improve the MDD-related dysconnectivity. The neuroplasticity of these networks was also related to improvements in anxiety and anhedonia.
Why is this study significant?
If you have been battling depression for some time now and have been trying multiple treatments to no avail, then you may want to consider ketamine infusions. If you’re curious to know more about ketamine’s mechanisms that make it an effective treatment for chronic pain, depression, and anxiety, you can read about it here.
Final Considerations
This was the first study that investigated imaging effects of serial ketamine infusions on resting-state functional connectivity. But despite the significant results of this study, there are a few limitations such as that ketamine was not compared with placebo in this study, unlike other randomized placebo-controlled trials. Also, a larger group is needed to validate the results of this study, especially because not everyone was able to complete the study.
There is no doubt, however, that ketamine’s neuroplastic effects do have a significant effect in patients with MDD, and it would be interesting to see future studies in this matter.
STUDY REFERENCED IN THIS BLOG: