Our understanding of how perception operates in real-world environments has been substantially advanced by studying both multisensory processes and “top-down” control processes influencing sensory processing via activity from higher-order brain areas, such as attention, memory, and expectations. As the two topics have been traditionally studied separately, the mechanisms orchestrating real-world multisensory processing remain unclear. Past work has revealed that the observer’s goals gate the influence of many multisensory processes on brain and behavioural responses, whereas some other multisensory processes might occur independently of these goals. Consequently, other forms of top-down control beyond goal dependence are necessary to explain the full range of multisensory effects currently reported at the brain and the cognitive level. These forms of control include sensitivity to stimulus context as well as the detection of matches (or lack thereof) between a multisensory stimulus and categorical attributes of naturalistic objects (e.g. tools, animals). In this review we discuss and integrate the existing findings that demonstrate the importance of such goal-, object- and context-based top-down control over multisensory processing. We then put forward a few principles emerging from this literature review with respect to the mechanisms underlying multisensory processing and discuss their possible broader implications.

This research was supported by grants from the Ministerio de Economia y Competitividad (PSI2013-42626-P), AGAUR Generalitat de Catalunya (2014SGR856), and the European Research Council (StG-2010 263145) to S.S-F, and the Swiss National Science Foundation (Grant #320030-149982 as well as the National Centre of Competence in Research project “SYNAPSY, The Synaptic Bases of Mental Disease” [Project 51AU40-125759]) and the Swiss Brain League (2014 Research Prize) to MMM. StO receives support from the Dutch Organisation for Scientific Research (Grant 406-11-068).