by the individual. However, the experiences derived from this pro-activity constrain the range of possible adaptations within the mental representations. Such progressive specialization arises from the constraints of the past and current learning environment. To alter representations, the environment demands improvements through small additions to the current mental state. This leads to partial instead of fixed representations that are assumed to occur in adults. Neuroconstructivism argues such end products do not exist. The brain's plasticity leads to ever-changing mental representations through individual proactivity and environmental interactions. Such a viewpoint implies that any current mental representations are the optimal outcome for a specified environment. For example, in developmental disorders like autism, atypical development arises because of adaptations to multiple interacting constraints, the same as normal development. However, the constraints differ and thus result in a different end-product. This view directly contrasts previous theories which assumed that disorders arise from isolated failures of particular functional modules. See also Constructivism (psychological school) Practopoiesis References Further reading Constructivism (psychological school) Animal developmental biology