How “Decisions” Really Get Made – Instantly and Unconsciously

Aside

My views on decision making, choice, executive function, cognitive workspace, emotions, consciousness I take from Paul Cisek – bottom line: “decisions” get made in the premotor brain areas, instantly.  The following is a bit technical but if you don’t understand something — Google it!

“Classic studies in cognitive psychology suggested the existence of a central executive system  that resides in the frontal lobes and is separate from sensorimotor control. However, in apparent conflict with this classic centralized view, neural activities related to decision-making are widely distributed and appear even in cortical and subcortical regions tradition- ally implicated in sensorimotor control.  This has led to suggestions that the brain simultaneously prepares multiple actions and decides between and them through a competition taking place within the sensorimotor system itself.

Decisions between goods
Economic theories suggest that humans make decisions between different goods by integrating all relevant factors (expected gains, potential risks, action costs, etc.) into a single variable capturing the subjective value of each offer.

Neurophysiological studies have suggested that this variable is encoded in the orbitofrontal cortex (OFC) and ventromedial prefrontal cortex (vmPFC).  In particular, neural activity in OFC correlates with the value of an option independent of other options, and adjusts its gain to reflect the full range of values presented in a given block of trials. This is consistent with the ‘good- based model’.  In the model,
–  all factors relevant for a choosing an offer are integrated in the OFC and vmPFC
–  these are compared and the largest one is chosen
–  Next, the appropriate action plan is computed to produce the required movement.

This model satisfies our subjective intuition about decisions: when choosing to reach for an orange, I think about the orange and not about muscles.  However, despite the intuitive appeal of the good-based model, it leaves open several important questions.

First, it predicts that motor planning begins only after decisions are made. However, many studies have shown that neurons in sensorimotor regions represent multiple potential targets and actions long before the animal decides between them.”

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s