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Prof. Dr. Anton J.M. Loonen


This is the fourth BLOG post on this Foundation’s site. The main new item to which I would like to draw your attention is a link to a YouTube video of a presentation. I had made this presentation back in May 2022, but it took until April 2023 for the YouTube video to be completely finished. Under the heading “Presentations,” you will find a link to the YouTube video, along with handouts with notes explaining each slide of the presentation. Under the heading “Figures” is a link to a PPTX file containing the jpg of our own figures (as always created by Lizanne Hennessey). Anyone may use these figures with appropriate acknowledgement of source and without modification. The presentation is intended for students (neuroscience, psychopharmacology, medicine, pharmacy, neuropsychology), psychiatry residents and psychiatrist-psychotherapists. This means that the story can be followed by these students without too much prior knowledge of brain anatomy.

As so often in my work, I use the philosophical premise that understanding the structure of brain parts is the best starting point for understanding their function. In turn, that structure is best understood by looking at how it developed during evolutionary development. This history partially and broadly repeats itself during human embryonic development.

I want to call special attention to a very ancient system running through the habenula complex that has only received attention in the last 10-15 years. This is because the habenula in humans in both hemispheres of the brain is only 20-30 mm³ in size and is also composed of several sub nuclei and subregions. The presentation will explain why this structure may nevertheless be of great importance in the development of the symptoms of the major mental disorders.