free will and neural activity

Posted comment on ´A biological basis for free will` by P. U. Tse published in New Scientist 2920, 8th June 2013.

SUMMARY

In his article, Tse explains his belief that free will can be explained by a new understanding of how neurons function. He says that not only the popular view that spikes of neuronal firing transmitted through neural circuits are responsible for thought and thinking is relevant, but also that firing neurons can quickly, but temporarily change the function of other neurons and themselves. He bases his view on research investigating the opening of specialised synaptic receptors in response to rapid bursts of spikes which then cause a change in the later responsiveness of the neurons. In this way, cells can respond that previously would not have done and hence, the whole circuit or network can be affected. This means that information is probably ´realised` in the brain at the circuit level and not at the single neuron level.
The link between neuronal firing and free will comes from according to Tse in his example of simple problem-solving with the individual brain setting criteria to solve that problem, internally going over the events, choosing the best option and then carrying it out. This where the self (that which according to Tse gives us conscious awareness of an event) then has some influence on what is thought and therefore, there is an opportunity to demonstrate free will. Therefore, any change in synaptic and firing strength from a previous experience will influence neural activity and can effect thought and any future events. In the example given by Tse in this article, the individual ´wills` the problem`s solution by manipulating the criteria to a point where only this answer is appropriate. Neural activity gives rise to consciousness which then is necessary for the rise of the correct action. This applies to actions where there is free will, but not to those that are repetitive or automated.
Tse concludes the article by stating that the understanding of neural activity implies that thinking and actions are therefore not random, but also not pre-determined which counters deterministic views of free will.

COMMENT

This article is interesting because it brings to the fore again the argument between free will and determinism by looking at thinking from a neural perspective. The example given by Tse was a simple problem-solving situation where the individual had the knowledge required and just needed to process it to get a viable solution. The type of processing was common as to was the criteria by which the solution was reached (e.g. only vegetarian recipe I know; or favourite vegetarian food).
Everybody has their own methods of solving problems and a popular technique used is the PISCO method of De Bono (1982) and described in Salt (2011) where the purpose or goal is defined, then the input (the relevant information or situation), the possible options the individual has by considering these two and past experiences (the solutions – S), the choice by making the decision (head vs heart) and finally the action taken as a result (the operation). One would think that free will is rife in such a process where conscious awareness is required and it can be (e.g. in novel problems, or complex ones), but there are circumstances when past experiences and habitual processing methods make it unnecessary. For example, the mere thought of the one vegetarian recipe that you know in the Tse example above ´blocks` all further processing (i.e. the problem is solved). Another example is where even after the second stage of defining the input, the individual finds himself already starting the movement that should form the last action stage. In these cases, free will is not in the form of constructing the options or making the choice, but comes in when the obvious solution is ignored.
The same can be said for actions. Clearly not all actions need to have conscious awareness, e.g. procedural memory and even if there is conscious awareness there is a delay between movement and conscious awareness of the movement (Libet, 1985) explained by the Baars Global Workspace Theory (1988). However, for some actions or sequences of actions conscious awareness is required in parts or in total. A simple fourteen-stage scenario consisting of choosing a drink from two offered as described in Salt (2013) showed that some parts could be considered deterministic (e.g. bottom-up control of the sensory pathways, top-down control using past experiences regarding object recognition, emotional values and exploratory tactics) whereas others were subject to the individual choosing (e.g. deliberate ignoring of relevant information and failing to implement known visual tactics). The free will in this case was exerted by choosing a new ´path` to follow.
But can free will be explained in terms of neural activity? Tse links synaptic reweighting to the role free will plays in decision-making and the neural correlates of consciousness and hence free will which is reliant on consciousness attempt to do so. Here, consciousness is explained by looking at neural activity not only at the lower level of signal transmission, firing cells, synaptic activity, brain area connectivity and brain waves for example, but also at the higher properties of brain plasticity, long-term potentiation, and increased connectivity with increased firing strength due to previous experiences. No firm conclusions have been formed. My own opinion (Salt, 2013) is that consciousness is a ´state` which occurs when neural activity allows it and this state is an indication that an individual has the ability to make deliberate choices, and actions whether positive or negative if desired. It is an indication that the individual can impose his ´will` on the working of real-time events, whether internally or externally sourced, and is an indication that the individual can ask, ´Is this what I want?` Conscious awareness need not be present on all tasks, all the time and hence, I support the compatibilist view that both deterministic and free will apply depending on development, situation, condition, experience and time for example. Unfortunately, until the neural correlates of consciousness can explain fully how consciousness is brought about this topic will continue to stimulate discussion.

Since we`re talking about the topic……..

….can we assume that conscious awareness to stop an intended action activates the same brain areas as to perform it?
…..if a task with variable rewards is repeated many hundreds of times, is it that the level of conscious awareness remains the same instead of tailing off if the reward was always the same?
….can imaging indicate differences in brain area activity for a dementia sufferer if they perform a conscious action, automatic action or exhibit free will and stop the actions at a point of their own choosing?

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