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Purpose: To explore the blood oxygen level dependent (BOLD) response in the posterior cingulate cortex (PCC) and the adjacent precuneus regions in healthy elderly adults during problem solving tasks., Materials and Methods: Eighteen participants (7 women, mean age of 63.6±6.0 years old) were analyzed. The functional magnetic resonance imaging (fMRI) tasks were simplified 4×4 Sudoku puzzles that were divided into simple tasks (using the row rule or the column rule to solve the puzzle) and complex tasks (using both the row and column rules to solve the puzzle)., Results: The mean accuracy on the simple task was higher than that on the complex task (P=0.04); the reaction time on the simple task was shorter than that on the complex task (P=0.001). On both tasks, the participants showed deactivation in the bilateral PCC/precuneus regions. The extent of deactivation on the complex task was greater than that on the simple task (left: P=0.04; right: P=0.04)., Conclusions: Healthy elderly adults showed deactivation in the bilateral PCC and precuneus regions during a problem solving task; in addition, the extent of deactivation was enhanced by increasing the difficulty of the problem solving task., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The methodologies of cognitive architectures and functional magnetic resonance imaging can mutually inform each other. For example, four modules of the ACT-R (adaptive control of thought - rational) cognitive architecture have been associated with four brain regions that are active in complex tasks. Activity in a lateral inferior prefrontal region reflects retrieval of information in a declarative module; activity in a posterior parietal region reflects changes to problem representations in an imaginal module; activity in the anterior cingulate cortex reflects the updates of control information in a goal module; and activity in the caudate nucleus reflects execution of productions in a procedural module. Differential patterns of activation in such central regions can reveal the time course of different components of complex cognition.

Two imaging experiments were performed--one involving an algebraic transformation task studied by Anderson, Reder, and Lebiere (1996) and the other an abstraction symbol manipulation task studied by Blessing and Anderson (1996). ACT-R models exist that predict the latency patterns in these tasks. These models require activity in an imaginal buffer to represent changes to the problem representation, in a retrieval buffer to hold information from declarative memory, and in a manual buffer to hold information about motor behavior. A general theory is described about how to map activity in these buffers onto the fMRI blood oxygen level dependent (BOLD) response. This theory claims that the BOLD response is integrated over the duration that a buffer is active and can be used to predict the observed BOLD function. Activity in the imaginal buffer is shown to predict the BOLD response in a left posterior parietal region; activity in the retrieval buffer is shown to predict the BOLD response in a left prefrontal region; and activity in the manual buffer is shown to predict activity in a motor region. More generally, this article shows how to map a large class of information-processing theories (not just ACT-R) onto the BOLD response and provides a precise interpretation of the cognitive significance of the BOLD response.

Based on adaptive control of thought-rational (ACT-R), a cognitive architecture for cognitive modeling, researchers have developed an information-processing model to predict the blood oxygenation level-dependent (BOLD) response of functional MRI in symbol manipulation tasks. As an extension of this research, the current event-related functional MRI study investigates the effect of relatively extensive practice on the activation patterns of related brain regions. The task involved performing transformations on equations in an artificial algebra system. This paper shows that the base-level activation learning in the ACT-R theory can predict the change of the BOLD response in practice in a left prefrontal region reflecting retrieval of information. In contrast, practice has relatively little effect on the form of BOLD response in the parietal region reflecting imagined transformations to the equation or the motor region reflecting manual programming.

Information technologies have been developed to facilitate driving performance and improve safety. However, there is a lack of computational methods that can take into account drivers’ adaptation to driving. That is, how behaviour changes with experience. Modelling the effect of driving experience on driver behaviour is important to the development of in-vehicle information technologies, because drivers at different skill levels may need different types or levels of assistance. Cognitive-architecture-based human performance modelling is a valuable method that can integrate different cognitive aspects underlying human behaviour such as skill levels and support quantitative simulation of behaviour. The study reported in this paper tested and examined computational models built in ACT-R (Adaptive Control of Thought-Rational) to account for the effect of driving experience on collision avoidance braking behaviour. The modelling results were compared with human data collected from a simulated driving experiment. The models produced braking behavioural results similar to the human results. Moreover, model predictions of three other emergent-braking scenarios were generally similar to and in the same order with the empirical results reported in previous studies. Future research can further integrate the method and results into intelligent driver assistance systems such as collision warning systems to better adjust the systems to the need of different drivers with different skill levels. [ABSTRACT FROM PUBLISHER]

Abstract: This research uses fMRI to understand the role of eight cortical regions in a relatively complex information-processing task. Modality of input (visual versus auditory) and modality of output (manual versus vocal) are manipulated. Two perceptual regions (auditory cortex and fusiform gyrus) only reflected perceptual encoding. Two motor regions were involved in information rehearsal as well as programming of overt actions. Two cortical regions (parietal and prefrontal) performed processing (retrieval and representational change) independent of input and output modality. The final two regions (anterior cingulate and caudate) were involved in control of cognition independent of modality of input or output and content of the material. An information-processing model, based on the ACT-R theory, is described that predicts the BOLD response in these regions. Different modules in the theory vary in the degree to which they are modality-specific and the degree to which they are involved in central versus peripheral cognitive processes. [Copyright &y& Elsevier]