Virtual personalities: Using computational modeling to understand within-person variability

- A neural network model of within and between person variability is presented.
- Expands on earlier work by Read et al. (2010).
- Behavior based on interaction between situation and structured motivational systems.
- Variability due to: situational affordances, bodily state, and motive competition.
- Motivational strength a multiplicative function of affordances and bodily state.

How can the same underlying psychological/neurobiological system result in both stable between-individual differences and high levels of within-individual variability in personality states over time and situations? We argue that both types of variability result from a psychological system based on structured, chronic motivations, where behavior at a specific point in time is a joint function of the current availability of motive affordances in the situation, current motivationally relevant bodily or interoceptive states, and the result of the competition among alternative active motives. Here we present a biologically-based theoretical framework, embodied in two different computational models, that shows how individuals with stable personality characteristics, can nevertheless exhibit considerable within-person variability in personality states across time and situations.