The Limbic System: Human Emotion
The remake of the EBS video involves explicit attention to the part of the brain historically noted to underlie emotion, i.e. the limbic system. This term was first used by Paul MacLean in 1949 and as a simplification, involves a combination of Papez' circuit and Yakovlev's conception of the orbitofrontal cortex as the regions where human emotion is grounded. As detailed below, my artistry is moreso focused on MacLean's inclusion of the amygdala, and ignores his vague references to the OFC (he mainly references the olfactory bulb, not the OFC!).
The remake of the EBS video involves explicit attention to the part of the brain historically noted to underlie emotion, i.e. the limbic system. This term was first used by Paul MacLean in 1949 and as a simplification, involves a combination of Papez' circuit and Yakovlev's conception of the orbitofrontal cortex as the regions where human emotion is grounded. As detailed below, my artistry is moreso focused on MacLean's inclusion of the amygdala, and ignores his vague references to the OFC (he mainly references the olfactory bulb, not the OFC!).
Video Representation of the Amygdala
As prepared by Floris Wouterlood in 2012, the following is a very reasonable video portrayal of the position of the amygdala in the brain, i.e. both where it's located and relation of the immediate surrounding structures, especially the hippocampus. As presented in my Blog wk#1 for term4, the MacLean limbic system animation starts with drawing the amygdala and then drawing of the hippocampus follows at about the midpoint of that animation. The MacLean limbic system animation shows relation of the structures similar to below, but obviously from the perspective of a diagrammatic visual.
As prepared by Floris Wouterlood in 2012, the following is a very reasonable video portrayal of the position of the amygdala in the brain, i.e. both where it's located and relation of the immediate surrounding structures, especially the hippocampus. As presented in my Blog wk#1 for term4, the MacLean limbic system animation starts with drawing the amygdala and then drawing of the hippocampus follows at about the midpoint of that animation. The MacLean limbic system animation shows relation of the structures similar to below, but obviously from the perspective of a diagrammatic visual.
Amygdalar Modelling
The image below will be used as a general reference for the structure of amygdala (Saygin et al, 2017). Despite searching dozens of papers, I have never actually encountered what one might consider a great model of the amygdala! This is probably because, in contrast to the hippocampus, it doesn't have a notably distinctive appearance. Beyond Saygin et al, the paper by Entis et al (2012) also contains reasonable images for the amygdala, and will be used to complement the Saygin image. Comparison of the images of either of those articles with the image in the Wouterlood video doesn't actually generate any extremely typical 'amygdalar' appearance, rather these comparisons show that the amygdala apparently has notable variability across subjects (Kim et al 2012). Indeed, while the amygdala is typically described as almond shaped (Kim et al 2011), it is difficult to conclude that any of the images in these 3 references closely resembles an almond!
The image below will be used as a general reference for the structure of amygdala (Saygin et al, 2017). Despite searching dozens of papers, I have never actually encountered what one might consider a great model of the amygdala! This is probably because, in contrast to the hippocampus, it doesn't have a notably distinctive appearance. Beyond Saygin et al, the paper by Entis et al (2012) also contains reasonable images for the amygdala, and will be used to complement the Saygin image. Comparison of the images of either of those articles with the image in the Wouterlood video doesn't actually generate any extremely typical 'amygdalar' appearance, rather these comparisons show that the amygdala apparently has notable variability across subjects (Kim et al 2012). Indeed, while the amygdala is typically described as almond shaped (Kim et al 2011), it is difficult to conclude that any of the images in these 3 references closely resembles an almond!
Houdini Schematized Amygdalar Modelling
As per the slide below, Houdini provides a useful 'help' tool function. It was straightforward to find and implement their edit geometry video (sideFX Houdini 2015); hitting '2 and enter' allows for easy manipulation of vertex points.
As per the slide below, Houdini provides a useful 'help' tool function. It was straightforward to find and implement their edit geometry video (sideFX Houdini 2015); hitting '2 and enter' allows for easy manipulation of vertex points.
Amygdalar Modelling GIF
As below, a gif was generated showing several of the modelling steps as conducted in Houdini. This modelling exercise was a good way for me to acquire a further introduction to some of the basics in Houdini. The modelling effort was primarily based on the 7 coronal images from Entis et al (2012), but with frequent reference to the images from Saygin et al (2017) and Mori et al (2017).
As below, a gif was generated showing several of the modelling steps as conducted in Houdini. This modelling exercise was a good way for me to acquire a further introduction to some of the basics in Houdini. The modelling effort was primarily based on the 7 coronal images from Entis et al (2012), but with frequent reference to the images from Saygin et al (2017) and Mori et al (2017).
Bibliography
Dalvi R (2017). Modeling Basics. https://www.sidefx.com/tutorials/modeling-basics/
Dell'acqua F, Schotten MT. (2013). A revised limbic system model for memory, emotion and behaviour. 37(8):1724-37.
Neurosci Biobehav Rev. doi: 10.1016/j.neubiorev.2013.07.001.
Entis JJ, et al. (2012). A reliable protocol for the manual segmentation of the human amygdala and its subregions using ultra-high resolution MRI. NeuroImage
Kim N, Kim HJ, Hwang J, Yoon SJ, Cho HB, et al. (2011) Amygdalar shape analysis method using surface contour aligning, spherical mapping, and probabilistic subregional segmentation. Neurosci Lett 488: 65–69.
Kim HJ, Kim N, Kim S, Hong S, Park K, et al. (2012) Sex differences in amygdala subregions: Evidence from subregional shape analysis. Neuroimage 60: 2054–2061.
MacLean P, (1949). Psychosomatic disease and the "Visceral Brain". Recent Developments Bearing on the Papez Theory of Emotion. Psychosomatic Medicine. vol 11, no. 6, p 338-353.
Moncrief J, (2015). Houdini, Basic Modeling Tools. https://app.pluralsight.com/player?course=introduction-houdini-15-2334&author=john-moncrief&name=introduction-houdini-15-2334-m2&clip=12
Mori S, et al (2017). Elucidation of White Matter Tracts of the Human Amygdala by Detailed Comparison between High-Resolution Postmortem Magnetic Resonance Imaging and Histology. Frontiers in Neuroanatomy. 11(16)1-14.
Saygin ZM, et al. (2017). High-resolution magnetic resonance imaging reveals nuclei of the human amygdala: manual segmentation to automatic atlas. NeuroImage 155 (2017) 370–382.
sideFX Houdini (2015). Edit Geometry. https://vimeo.com/142494489
sideFX Houdini (2015). Edit Points. https://vimeo.com/122358770
Wouterlood F (2012). 3D Brain from MRI 6 Amygdala. https://www.youtube.com/watch?v=YB9rs4tEAaE
Dalvi R (2017). Modeling Basics. https://www.sidefx.com/tutorials/modeling-basics/
Dell'acqua F, Schotten MT. (2013). A revised limbic system model for memory, emotion and behaviour. 37(8):1724-37.
Neurosci Biobehav Rev. doi: 10.1016/j.neubiorev.2013.07.001.
Entis JJ, et al. (2012). A reliable protocol for the manual segmentation of the human amygdala and its subregions using ultra-high resolution MRI. NeuroImage
Kim N, Kim HJ, Hwang J, Yoon SJ, Cho HB, et al. (2011) Amygdalar shape analysis method using surface contour aligning, spherical mapping, and probabilistic subregional segmentation. Neurosci Lett 488: 65–69.
Kim HJ, Kim N, Kim S, Hong S, Park K, et al. (2012) Sex differences in amygdala subregions: Evidence from subregional shape analysis. Neuroimage 60: 2054–2061.
MacLean P, (1949). Psychosomatic disease and the "Visceral Brain". Recent Developments Bearing on the Papez Theory of Emotion. Psychosomatic Medicine. vol 11, no. 6, p 338-353.
Moncrief J, (2015). Houdini, Basic Modeling Tools. https://app.pluralsight.com/player?course=introduction-houdini-15-2334&author=john-moncrief&name=introduction-houdini-15-2334-m2&clip=12
Mori S, et al (2017). Elucidation of White Matter Tracts of the Human Amygdala by Detailed Comparison between High-Resolution Postmortem Magnetic Resonance Imaging and Histology. Frontiers in Neuroanatomy. 11(16)1-14.
Saygin ZM, et al. (2017). High-resolution magnetic resonance imaging reveals nuclei of the human amygdala: manual segmentation to automatic atlas. NeuroImage 155 (2017) 370–382.
sideFX Houdini (2015). Edit Geometry. https://vimeo.com/142494489
sideFX Houdini (2015). Edit Points. https://vimeo.com/122358770
Wouterlood F (2012). 3D Brain from MRI 6 Amygdala. https://www.youtube.com/watch?v=YB9rs4tEAaE
