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The Nobel Prize for Chemistry has been awarded to Alan Heeger, a physicist at the University of California, Santa Barbara, and two chemists, Alan MacDiarmid of the University of Pennsylvania, Philadelphia and Hideki Shirakawa of the University of Tsukuba, for their roles in the development of electrically conductive polymers.

Heeger and colleagues report that activated B cells dynamically regulate the expression of complement regulatory proteins via the transcription factor BCL6. C3 convertase activity and C3aR1–C5aR1 signaling were both necessary for optimal B cell activation and germinal center formation.

Topological photonics could impact the scalability of integrated photonics, but it has shown limited reconfigurability to date. Here, the authors demonstrate reprogrammable integrated photonics as a nearly universal platform for topological models.

Denison and colleagues present a computational account of attention—temporal dynamic normalization—which extends the idea of limited attentional resources across space at a single moment to a formal account of limited resources across time at a single location.

An on-surface synthetic route for the regio- and stereoselective coupling of indenyl moieties, affording the design of π-conjugated acenoindenylidene polymers on Au(111), is reported. The relationship between the structural parity of the polymers and their electronic properties reveals the emergence of highly delocalized soliton quasiparticles in odd-membered polymers.

DEED captures the balance between entropy gains and costs, allowing the correct classification of functional synthesizability of multicomponent ceramics, regardless of chemistry and structure, and provides an array of potential new candidates, ripe for experimental discoveries.

Spin and charge dynamics are inevitably linked, the study of the one often illuminating the other. Here, the authors study spin relaxation in ambipolar polymers and, backed by simulations, show how charge dynamics and wavefunction localization together set relaxation times up to room temperature.

Polymers commonly are semiconducting or insulating because of a sizable energy gap in the density of states around the Fermi level. Yet, the phase transition from topologically trivial to non-trivial in on-surface synthesized π-conjugated polymers, due to a change of resonant form, stabilizes narrow bandgaps and bears in-gap zero-energy edge states in the non-trivial phase.

Evidence suggests that covert visual attention can improve behavioral performance by modulating contrast or response gain. Herrmann et al. find that the size of the stimulus and the attention field determine which mechanism is used. These results support predictions of the normalization model of attention.

People can direct attention to specific moments that they anticipate will be relevant to their goals. Here, the authors show that voluntary temporal attention engages both periodic and transient modulations of visual cortical activity to improve perception at precise time points.

In humans, stroke damage to V1 causes large visual field defects. Spared V1 activity prior to training predicts the amount of training-induced recovery in luminance detection sensitivity. Moreover, visual training changes population receptive field properties within residual V1 circuits.

People with autism are known for their inflexible behavior. Using a perceptual learning protocol, the authors demonstrate initially efficient learning in observers with autism, followed by anomalously poor learning when the target location is changed (over-specificity). Furthermore, over-specificity can be circumvented by a specifically designed protocol that reduces stimulus repetitions.

The detection of a moving object's velocity by the visual system is thought to require several sequential computational steps. Bradley and Goyal outline current theoretical models that explain how local-velocity estimates are obtained and integrated, and consider the experimental evidence for each model.

The authors examined neuronal responses in V1 and V2 to synthetic texture stimuli that replicate higher-order statistical dependencies found in natural images. V2, but not V1, responded differentially to these textures, in both macaque (single neurons) and human (fMRI). Human detection of naturalistic structure in the same images was predicted by V2 responses, suggesting a role for V2 in representing natural image structure.

Speed preferences in MT neurons are found to be unaffected by changes in stimulus pattern, supporting the hypothesis that these neurons represent retinal image velocities.

Normalization computes a ratio between the response of an individual neuron and the summed activity of a pool of neurons. Here, the authors review the evidence that it serves as a canonical computation — one that is applied to processing different types of information in multiple brain regions in multiple species.

By demonstrating that fMRI responses in human MT+ increase linearly with motion coherence and comparing these responses with slopes of single-neuron firing rates in monkey MT, a new paper provides the best evidence so far that fMRI responses are proportional to firing rates.