Keynote Series: Insights into attention orienting with Dr. Emma Burrows

By Alejandra Lopez-Castro 

Attention is the cognitive process of selectively focusing on specific stimuli or tasks while ignoring others. It is a fundamental aspect of human cognition, allowing us to filter out irrelevant information and concentrate on what is important. Attention is crucial for learning, memory, and decision-making, and its impairments are associated with various neuropsychological disorders such as attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, and Alzheimer's disease. On the other hand, attention is difficult to study in humans because it’s a complex and multifaceted process that involves multiple brain regions and neural networks. To address this problem, Dr. Emma Burrows and her research group have been doing exceptional assets to attention research. Believe it or not, mice can orient their attention in a similar way to humans, and by using mouse models, researchers can manipulate genes and neural circuits to determine their causal role in attention orienting.

This was the principle of Dr. Burrows led by first author Shuting Li.study, which resulted in an adaptation of the Posner cueing task, a method used to study attention orienting in both humans and other animals. The researchers adapted the task for mice using touchscreen operant chambers. Mice were trained to nose-poke a central stimulus, after which a spatial cue was briefly presented on either the left or right side of the screen. After a short delay, a target stimulus appeared on either the left or right side. The mice had to respond by touching the screen where the target appeared. If the cue correctly predicted the target location (valid trial), the mice received a liquid reward. If the cue was on the opposite side of the target (invalid trial), no reward was given.

Mice underwent extensive training to learn the task, with the cue duration and cue-target interval gradually decreasing over sessions. They were trained on both an exogenous version, where the cue was non-predictive (50% valid), and an endogenous version, where the cue was initially 100% predictive of the target location. The purpose of training the mice to nose-poke the central stimulus before each trial was to control their starting position and mimic how humans perform the Posner task. By maintaining their nose-poke until the target appeared, the researchers could accurately measure the mice's reaction times.

The results showed that mice responded faster and more accurately on valid trials compared to invalid trials in both the exogenous and endogenous versions of the task. This demonstrates that mice, like humans, can orient their attention based on both stimulus-driven and goal-driven cues. In the exogenous task, mice had a 79 millisecond (ms) "orienting effect": their reaction times were 79 ms slower on invalid trials compared to valid trials. They also responded more on the wrong side and had lower accuracy on invalid trials.

The endogenous task showed an even larger orienting effect of 124 ms. Mice made more anticipation errors (leaving the central stimulus before target onset) on trials with longer nose-poke durations, suggesting they were actively predicting the target location based on the cue. The larger orienting effect in the endogenous task compared to the exogenous task suggests that goal-driven attention orienting requires more cognitive resources than stimulus-driven orienting. When mice could predict the target location based on the cue, they were able to orient their attention more strongly.

The researchers also tested the effects of two attention-modulating drugs, methylphenidate (MPH) and atomoxetine (ATX), on task performance. MPH primarily targets the dopamine system while ATX acts on the norepinephrine system. Both are commonly used to treat ADHD in humans. However, neither drug altered the magnitude of the orienting effect in the exogenous task. This suggests that while MPH and ATX modulate overall performance, they do not specifically impact the attention-orienting process itself.

In conclusion, this study demonstrates that mice can orient their attention in a remarkably similar way to humans. The touchscreen task provides a powerful new tool to probe the neurobiology of attention orienting in mice. By combining this behavioral assessment with cutting-edge neuroscience techniques, we can gain insight into this fundamental cognitive process.

So next time you see a mouse scurrying around, remember - it's not just looking for cheese, it's orienting its attention to the world around it! With the help of this new task, we may soon understand the neural basis of attention in mice and what it can tell us about attention in humans.

If you want to know more about Dr. Burrows' work, don't miss her keynote presentation and check out our interview with her here.

Source

Li, S., May, C., Hannan, A.J. et al. Assessing attention orienting in mice: a novel touchscreen adaptation of the Posner-style cueing task. Neuropsychopharmacol. 46, 432–441 (2021). https://doi.org/10.1038/s41386-020-00873-8