248 Self and the Phenomenon of Life
b2726 Self and the Phenomenon of Life: A Biologist Examines Life from Molecules to Humanity “9x6”Fig. 11.2. Flow chart of decision-making. The execution of a voluntary action pro-
ceeds in stages. First, the background consists of the innate and acquired make-up of the
agent. The dynamics of decision-making are the interplay of the external stimulus with
memory, emotion, rational thinking, and idiosyncrasy. Idiosyncrasy confers individual
bias at a given instant, making free will somewhat unpredictable and irreproducible.
I use the term “idiosyncrasy” broadly to accommodate all the contingencies that can arise
in the brain out of complex interactions, including incidental variables, deterministic
chaos, catastrophic phenomenon, and other metastable conditions. A very small bias at
the moment can tip the balance of decision one way or the other. From this dynamics,
a goal is set and a drive is generated to achieve it. Finally, a command is sent from the
motor areas to the skeletal muscles to start an action. (Please note that in humans a
decision need not be immediately translated into action.)
Fig. 11.3. Diagram showing neuroanatomical pathways of volition. Starting from
the left, a decision is initiated in the prefrontal cortex upon interaction with the limbic
system. The decision is translated into an action through the motor areas of the cerebral
cortex. SMA, supplementary motor area; PMd, pre-motor area (dorsal part); M1, pri-
mary motor area. Note that the sense of agency of an act is achieved when feedback
information matches the feed-forward in the parietal cortex. [See Note 30; permission
Springer Berlin.]