A somato-cognitive action network alternates with effector regions in motor cortex. Link below and it will be greek to most people. But let me just highlight a key paragraph which should be easy for many people to understand.
Two behavioral control systems are interleaved in human M1.
One well-known system consists of effector-specific circuits for precise, isolated movements of highly specialized appendages—fingers, toes and tongue—the type of dexterous motion needed for speaking or manipulating objects.
A second, integrative output system, the SCAN, is more important for controlling the organism as a whole. The SCAN integrates body control (motor and autonomic) and action planning, consistent with the idea that aspects of higher-level executive control might derive from movement coordination. The SCAN includes specific regions of M1, SMA, thalamus (VIM and CM), posterior putamen and the postural cerebellum, and is functionally connected to dACC regions linked to
free will, parietal regions representing movement intentions, and insular regions for processing somatosensory, pain and interoceptive visceral signals. The apparent relative expansion of SCAN regions in humans could suggest a role in complex actions specific to humans, such as coordinating breathing for speech, and integrating hand, body and eye movement for tool use.
A common factor across this wide range of processes is that they must be integrated if an organism is to achieve its goals through movement while avoiding injury and maintaining physiological allostasis. The SCAN provides a substrate for this integration, enabling pre-action anticipatory postural, breathing, cardiovascular and arousal changes (such as shoulder tension, increased heart rate or ‘butterflies in the stomach’). The finding that action and body control are melded in a common circuit could help explain why mind and body states so often interact.
So what changed from Nov last year vs lets pick an aribtrary year but it is actually relevant "2004"
What changed from 2004 and Nov 2022 is we used to think
a) the motor strip was a continuous strip where there were different regions for like toes, heels, knees, hips, waist, and so on all the way to head, mouth, eyes, etc. Now we see it is 6 regions and it alternates with 3 hubs that integrates large body movements, and 3 regions with the toes, fingers, and mouth / voice box which do finer control behavior.
b) we learned there is a "back door" connection with another network called the Cingulo Opercular Network. A network we known about since 2008 for there are two main "control" networks with planning, problem solving, executive functioning.
i) The Frontal Parietal Control Network starts the task and adjust control such as goals when things are obviously not working
ii) the Cingulo Opercular Network provides stable ‘set-maintenance’ over entire task and time epochs. Aka it is is modulating arousal, noticing errors, keeping up motivation, dealing with frustration, and so on. It is the part of the brain that notices things are weird happening with music where FPCN may notice the general pattern from previous memories and the CO network notices things you previously did not notice and this can trigger positive or negative valience for example joy or disqust and so on.
Well this Cingulo Opercular Network we known about for a while, but we learned today it is connected directly to the motor area of the brain that moves muscles directly instead of being mediated between the pre motor and the supplementary motor area. Aka we thought there was a front door, and now we know the CO network also connects to a back door
And this will make sense with anyone who has the experience of feeling alive, feeling pain, feeling excitement nervousness, etc. It explains also things tied to parkinson, movement disorders, performance-executive function disorders, etc.
