Letter-position tolerance varies across languages. This observation suggests that the neural code for letter strings may also be subtly different. Although language-specific models remain useful, we should endeavor to develop a universal model of reading acquisition which incorporates crucial neurobiological constraints. Such a model, through a progressive internalization of phonological and lexical regularities, could perhaps converge onto the language-specific properties outlined by Frost.

Cohen Kadosh & Walsh (CK&W) neglect the solid empirical evidence for a convergence of notation-specific representations onto a shared representation of numerical magnitude. Subliminal priming reveals cross-notation and cross-modality effects, contrary to CK&W's prediction that automatic activation is modality and notation-specific. Notation effects may, however, emerge in the precision, speed, automaticity, and means by which the central magnitude representation is accessed.

Can we ever experimentally disentangle phenomenal consciousness from the cognitive accessibility inherent to conscious reports? In this commentary, we suggest that (1) Block's notion of phenomenal consciousness remains intractably entangled with the need to obtain subjective reports about it; and (2) many experimental paradigms suggest that the intuitive notion of a rich but non-reportable phenomenal world is, to a large extent illusory – in a sense that requires clarification.

Background. Failure to resist chronic obsessive–compulsive symptoms may denote an altered state of cognitive control. We searched for the cerebral regions engaged in this dysfunction.

Method. Differences in brain regional activity were examined by event-related functional magnetic regional imaging (fMRI) in a group of adolescents or young adults (n=12) with childhood-onset obsessive–compulsive disorder (OCD), relative to healthy subjects. Subjects performed a conflict task involving the presentation of two consecutive and possibly conflicting prime and target numbers. Patients' image dataset was further analysed according to resistance or non-resistance to symptoms during the scans.

Results. Using volume correction based on a priori hypotheses, an exploratory analysis revealed that, within the prime-target repetition condition, the OCD subjects activated more than healthy subjects a subregion of the anterior cingulate gyrus and the left parietal lobe. Furthermore, compared with ‘resistant’ patients, the ‘non-resistant’ OCD subjects activated a bilateral network including the precuneus, pulvinar and paracentral lobules.

Conclusions. Higher regional activations suggest an abnormal amplification process in OCD subjects during the discrimination of repetitive visual stimuli. The regional distribution of functional changes may vary with the patients' ability to resist obsessions.

Quartz & Sejnowski's (Q&S's) constructivist manifesto promotes a return to an extreme form of empiricism. In defense of learning by selection, we argue that at the neurobiological level all the data presented by Q&S in support of their constructive model are in fact compatible with a model comprising multiple overlapping stages of synaptic overproduction and selection. We briefly review developmental studies at the behavioral level in humans providing evidence in favor of a selectionist view of development.