●Interacting social minds. Phelps, E. A. Nature Neuroscience September (2004) A review of Chris Frith and Daniel Wolpert's book The Neuroscience of Social Interaction: Decoding, Influencing and Imitating the Actions of Others.

●Optimality principles in sensorimotor control. Todorov, E. Nature Neuroscience September (2004) Many theories of motor functions are based on 'optimal performance' that emphasizes learning and adaptation. This article reviews new approaches that stresses the relationship between high-level goals and the real-time sensorimotor control strategies that are most suitable for accomplishing these goals.

●Diagnosing prion diseases: needs, challenges and hopes. Soto, C. Nature Reviews Microbiology October (2004)

●Prion's progress. Cashman, N. R. Nature Cell Biology September (2004) A review of Stanley Prusiner's book Prion Biology and Diseases (second edition).

●An animal model of vascular amyloidosis. Ghiso, J. & Wisniewski, T. Nature Neuroscience September (2004) A new study, discussed in this News and Views article, reports the first animal model of hereditary cerebral haemorrhage with amyloidosis-Dutch type. This model might also give insights into amyloid-β deposition in Alzheimer's disease.

●Maiming mitochondria in familial ALS. Dawson, V. L. Nature Medicine September (2004) This News and Views article reports on two recent studies that show a causal link between mutation in SOD1, impairment of mitochondrial function and motor neuron degeneration in familial amyotrophic lateral sclerosis.

●Feeding the brain. Peppiatt, C. & Attwell, D. Nature 9 September (2004) It is thought that an increase in calcium in astrocytes could dilate arterioles and increase cerebral blood flow, but new evidence shows that the opposite could also be true. This News and Views article discusses this study and the controversy about the role of astrocytes in regulating cerebral blood flow.

●β-Cell precursors — a work in progress. Weir, G. C. & Bonner-Weir, S. Nature Biotechnology September (2004) This News and Views article discusses the unexpected finding that single murine adult pancreatic precursor cells can generate progeny with characteristics of neuroectodermal and pancreatic cells, including insulin-producing β-cells.

●Cell survival guide. Fearon, R. R. & Cho, K. R. Nature 2 September (2004) This News and Views article reviews the surprising discovery that netrin-1 can promote tumour growth in the mouse intestine, and that this might be mediated by interference with cell-death pathways.