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Abstract The emerging field of Evolutionary Computation (EC), inspired by neo‐Darwinian principles (e.g. natural selection, mutation, etc.), offers developmental psychologists a wide array of mathematical tools for simulating ontogenetic processes. In this brief review, I begin by highlighting three of the approaches that EC researchers employ (Artificial Life, evolutionary robotics and comparative stochastic optimization). I then focus on the advantages of using comparative stochastic optimization as a method for studying development. As a concrete example, I illustrate the design and implementation of an EC model that simulates the development of reaching in young infants.

Infants' developing causal expectations for the outcome of a simple tool‐use event from ages 8 to 12 months were investigated. Causal expectations were studied by comparing infants' developing tool‐use actions (i.e. as tool‐use agents) with their developing perceptual reactions (i.e. as tool‐use observers) to possible and impossible tool‐use events. In Experiment 1, tool‐use actions were studied by presenting infants, ages 8 and 12 months, with tool‐use object‐retrieval problems. In Experiment 2, a second age‐matched sample of infants watched a comparable series of possible and impossible tool‐use events in which a tool was used to retrieve a goal‐object. Two core related findings were made. First, infants' causal action and causal perception develop in parallel. In both action and perception, supporting tool‐use develops before surrounding tool‐use. Second, infants' tool‐use action develops before their causal perception of comparable tool‐use events. The findings support the constructivist hypothesis that infants' causal actions may develop before and inform their causal perceptions.

Trial‐and‐error learning strategies play a central role in sensorimotor development during early infancy. However, learning to reach by trial‐and‐error normally requires a slow and laborious search through the space of possible movements. We propose a computational model of reaching based on the notion that early sensorimotor control is driven by the generation of exploratory movements, followed by the selection and maintenance of adaptive movement patterns. We find that, instead of exhaustively exploring the full search space of movement patterns, the model exploits several emergent constraints that limit the initial size of the movement search space. These constraints exploit both mechanical and kinematic properties of the reaching task. We relate these results to the development of reaching during infancy, and discuss recent findings that have identified similar constraints in young infants.

AbstractWe recently proposed a multi‐channel, image‐filtering model for simulating the development of visual selective attention in young infants (Schlesinger, Amso & Johnson, 2007). The model not only captures the performance of 3‐month‐olds on a visual search task, but also implicates two cortical regions that may play a role in the development of visual selective attention. In the current simulation study, we used the same model to simulate 3‐month‐olds' performance on a second measure, the perceptual unity task. Two parameters in the model – corresponding to areas in the occipital and parietal cortices – were systematically varied while the gaze patterns produced by the model were recorded and subsequently analyzed. Three key findings emerged from the simulation study. First, the model successfully replicated the performance of 3‐month‐olds on the unity perception task. Second, the model also helps to explain the improved performance of 2‐month‐olds when the size of the occluder in the unity perception task is reduced. Third, in contrast to our previous simulation results, variation in only one of the two cortical regions simulated (i.e. recurrent activity in posterior parietal cortex) resulted in a performance pattern that matched 3‐month‐olds. These findings provide additional support for our hypothesis that the development of perceptual completion in early infancy is promoted by progressive improvements in visual selective attention and oculomotor skill.