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People typically perceive the motion and depth of objects correctly even during walking or running, when visual inputs change markedly. The authors show that this accurate perception is achieved by inferring the observer’s viewing geometry from optic flow.

"Motion perception depends on reference frames, but it is unclear what the brain’s reference frame is. Here, the authors show that human motion perception follows a hierarchical causal inference process, dynamically segmenting visual scenes into nested reference frames.”

Research in multisensory processing has exploded in recent years, but different experimental and theoretical approaches have yielded conflicting or seemingly unrelated results. In this Review, Fetschet al. present a body of work that attempts to integrate and accommodate these findings.

Using a multisensory cue-conflict task, the authors report that monkeys employ the optimal strategy of weighting each cue in proportion to its reliability, and that population decoding of neural responses from area MSTd predicts behavioral cue weighting. This behavior is further linked to the specific computations by which single neurons combine their inputs, consistent with recent theories of optimal probabilistic neural computation.

Observers can combine multiple sensory cues to achieve greater perceptual sensitivity, but little is known about the underlying neuronal mechanisms. Gu and colleagues found neurons in the dorsal medial superior temporal area of the macaque that had responses that were consistent with the signals expected to result from cue combination.

Choice-related signals in neuronal activity may reflect bottom-up sensory processes, top-down decision-related influences, or a combination of the two. Here the authors report that choice-related activity in VIP neurons is not predictable from their stimulus tuning, and that dominant choice signals can bias the standard metric of choice preference (choice probability).

It is shown that in addition to the well-documented representation of retinal motion, primate area middle temporal area neurons are sensitive to the relative depth of stimuli defined by motion parallax. Motion parallax is a powerful depth cue that arises when the observer is moving due to near and far objects moving across the retina at different speeds.

Sasaki et al. demonstrate that neurons in the macaque parietal cortex (ventral intraparietal area) flexibly represent object motion in either a head-centered or world-centered reference frame depending on the requirements of the task.

The divisive normalization model has been influential in understanding the response properties of neurons in the visual system. Here the authors show that this computational framework can also provide a simple unifying account of the key features of multisensory integration by neurons, a research area that has traditionally been characterized by empirical principles.

Extraretinal signals such as efference copy are generally thought to be critical for discounting visual image motion caused by eye movements. However, theoretical work suggests that eye rotations could be estimated directly from optic flow. Here the authors show that MT neurons use such ‘dynamic perspective’ cues to disambiguate depth.

Functional links between neuronal activity and perception are studied by examining trial-by-trial correlations (choice probabilities) between neural responses and perceptual decisions. Here the authors report that subcortical vestibular neurons show robust choice probabilities if they selectively represent self-translation, suggesting that choice-related activity emerges from a critical transformation of vestibular signals.

Analysis of advanced cancer patients treated with immune-checkpoint inhibitors shows that tumor mutational burden, as assessed by targeted next-generation sequencing, predicts survival after immunotherapy across multiple cancer types.

Gonçalo Abecasis and colleagues report a large-scale meta-analysis of genome-wide association studies for age-related macular degeneration (AMD), including over 17,100 advanced cases and 60,000 controls. They identify seven loci newly associated with AMD and report pathway analysis that shows enrichment in the complement system and atherosclerosis signaling.

Correlations in firing rate between pairs of neurons can change depending on task and attentional demands. This new finding suggests that measuring correlations can help to reveal how neural circuits process information.

Moving stimuli evoke a response from a large number of neurons in cortical area MT. A new study investigates how perceptual decisions may arise from that population response, with important implications for theories of neural coding.

Analyses of the recovery of marine populations, habitats and ecosystems following past conservation interventions indicate that substantial recovery of the abundance, structure and function of marine life could be achieved by 2050 if major pressures, including climate change, are mitigated.