Mobilisation of neural resources for temporal attention

What are temporal expectations?

Information from past experiences regarding the timing of events is crucial to enhance performance in an ongoing situation. Imagine a sprinter preparing for the ‘ready, set, go’ signal – efficient temporal expectations can win the race and errors in expectation can result in disqualification. These formations of sensory-driven temporal expectations require learning mechanisms in the brain to establish the timing of incoming sensory input as well as the underlying neural resources to form expectations about future events. This dynamic processing requires coordination between primary sensory systems, association sensory areas (such as the posterior parietal cortex), and executive centres in the prefrontal cortex. However, many questions remain regarding the underlying neural resources supporting the formation of temporal expectations in the brain and how information processing across multiple sensory systems can alter these dynamics.

Multisensory representations
of the environment

Real world events often stimulate more than one sensory modality – for instance, under normal conditions we rarely see without hearing. Since natural environments constantly present us with random and noisy sensory stimulation through which we must interpret behaviourally relevant information, utilising input from multiple senses may enhance our perceptual representations and allow us to form more efficient temporal expectations to improve behavioural outcomes. However, knowledge about temporal regularities may not always be easily transferred across sensory modalities and the way we use multisensory cues can differ across our lifespan, with the elderly often benefiting more from multisensory stimulus representations. Therefore, in this project we employ combinations of unisensory and multisensory input to probe the mobilisation of neural resources during temporal processing.

Neural circuits:
from mice to men

The posterior parietal cortex is known to play a role in multisensory integration and temporal attention and is ideally positioned to integrate information from both primary sensory cortices and executive control centers in the prefrontal cortex. From humans to rodents, reciprocal connections with primary sensory cortices provide specific sensory inputs to the posterior parietal cortex, but also process task-dependent information. Reciprocal connections with the prefrontal cortex may play an important role in associative memory formation and feedback processing. Recent work on the effect of expectancy based on the presentation of temporally predictable stimulus sequences has revealed that humans and animals are able to extract regularities. While neuroimaging techniques allow us to investigate task-specific changes in fMRI responses in humans, mice offer the additional advantage to directly observe and manipulate activity within neuronal circuits down to the single-cell level. To this end, we relate behavioural readouts with fMRI in humans and two-photon calcium activity in mice, and directly compare fMRI readouts between species. Therefore, on the micro- and meso-scale level, our project targets local neurocircuitry within mouse posterior parietal cortex, as well as intracortical circuits on the macro-scale, also involving prefrontal cortex and sensory-specific areas in both humans and animals.