Corona Pollentia

The Corona Pollentia is the part of the brain that adapts to and controls the 'powers' that parahumans develop and display.

Corona Pollentia
The Corona Pollentia is the part of the brain that is adapted to and connects the powers that come from individual Entity Shards. With the appearance of this formation, usually accompanied by a dream, the subject becomes able to trigger. The Corona Pollentia is a startlingly common feature, even in unpowered people.

Gemma
The Gemma is the part of the Corona Pollentia that controls the active use of a parahumans' abilities and powers, the same way there are parts of the brain that allow regular humans to coordinate and move their hands. Artificial Gemmas were known to give powers that were maladapted to stressful engagements.

Size, Location, and Integration
The size, shape, and location of the Corona and the Gemma changes from parahuman to parahuman. Usually, it starts as 1-1.6 inch-sized body settled between the frontal and the parietal lobes.

During the trigger event, Corona gets a spurt of development. It is a partial reason for people blacking out. Corona expands slightly, veins swell.But the entity can still see fallout effects. There are parallels in memory storage. Not many, but there may be glimmers where the subject is capable of perceiving the information stored in the shard as the connections are formed. For good measure, the entity breaks up one shard cluster, tunes it, then codes the effect into each and every shard. It studies the host species further, refines, attunes. It takes time, but the entity forms a sufficient safeguard. The host species will forget any significant details. The broken shard is cast off, joining countless others. It will bond to a host. The entity looks forward, checking. After the target planet has revolved thirty-three times around its star, this shard will connect to a host. [...] This time, the shard settles in the male, then immediately shifts to the more distressed female. Insinuation. The shard connects to the host’s neural network. The bond is created. The shard opens the connection as the stress peaks, and the host doubles over in pain, bewildered, stunned. The shard then forms tendrils that contact each individual in the area. It retains traces of the entity’s tampering, of the studies in psychology, awareness and memory, and is quick to adapt. It finds a manner in which it can operate, then alters itself, solidifying into a particular state. The remainder of the functions are discarded, the ones in the shard itself are rendered inert to conserve power, while the ones in the host fall away, are consumed by the shard. The host’s neural network changes once more. The female disappears from the awareness of the hostile ones that surround it. The entity looks to the future, to see if this is sustainable, efficient. - excerpt from Interlude 26 Although it is still hard to distinguish a small but active Corona from bigger but inactive.

Young triggers have more pronounced Corona Pollentia with a noticeable effect called 'dimpling,' as if it is pressed down into the brain, and, sometimes, expanded webbing, enveloping the brain.

It is possible to get an impression of power expression from how Corona Pollentia is integrated with the brain. E.g. strong frontal lobe connection indicates Thinker-type perception powers, and Masters would get a stronger emphasis on the cerebellum.

The unpredictable size and location of the Corona Pollentia and Gemma prevents people from removing them surgically as, most of the time, trial and error does not work. However, sufficiently precise surgery is capable of removing them, in principle; Contessa's Thinker power allows her to inflict precise damage to the Corona Pollentia in such a way that the target loses access to their powers, and Cauldron makes use of this to remove powers strategically.

Trivia

 * Cauldron vials trigger powers regardless of whether or not the subject has a Corona Pollentia. In those that already have one, there is a greater chance of deviant powers. In those that do not have a Corona Pollentia, one develops as they trigger.
 * The size and shape of the Corona Pollentia is also stated to depend on the powers of the parahuman with it and how their powers work.