Did You Zone Out—or Is It a Multimodal Filtering Problem?

“Zoning out” is often caused by multimodal competition: your visual and auditory systems are both demanding access to limited processing resources, and the control networks that normally select what matters and suppressing what doesn’t get overloaded. When that selection fails, the brain often defaults to not processing one channel (frequently hearing) or to a broader shutdown of active reasoning and working memory.

What actually happens when sight and sound compete

1. Capacity is limited, and priority must be assigned.

   Human perceptual processing is not infinite. Under high visual load (dense slides, rapid motion, effortful reading), the brain measurably reduces auditory processing, This effect is known as inattentional deafness. EEG and MEG studies show weakened time-locked auditory responses when the visual task is demanding, indicating down-regulation of the auditory processes rather than simple distraction.

   
   

2. Control hubs in the brain have the potential to bias one modality and suppress the other.

   Attentional control (frontoparietal cortex) biases sensory pathways toward relevant inputs. When you choose to “look hard,” visual cortex can be preferentially facilitated while auditory cortex activity is dampened, and vice-versa. Keeping both at peak performance is difficult for some, but can be done with training.

   
   

3. The thalamus gates the traffic.

   The thalamic reticular nucleus (TRN) sits at a strategic choke point in thalamo-cortical loops and is strongly implicated in cross-modal gating, controlling how much visual vs. auditory information reaches cortex. When both channels compete, TRN-mediated inhibition can favor one stream at the expense of the other. Again, this can be trained.

   
   

4. Working memory is collateral damage.

   Under heavy visual working-memory load, studies show deactivation of primary auditory cortices and tighter coupling among regions serving the visual task. Practically, that means when you’re trying to hold complex visuals in mind, spoken input becomes easier to miss even when it’s relevant.

   
   

5. Context matters: congruent vs. irrelevant sounds.

   The brain integrates across senses when inputs align (e.g., mouth movements and speech) and tends to suppress inputs that are semantically or task-irrelevant. Task relatedness is a key moderator: sounds tied to the visual goal can still capture attention; unrelated sounds are more likely to be filtered out or never registered consciously for most people. However, those with ADD/Autism or other conditions can struggle with this filtering causing one to shut down, get frustrated, ignore everything, or become impulsive. These reactions can be reduced significantly when you train the brain to handle multiple inputs and/or conflicting inputs.

   
   

Why people “shut down”

When vision and hearing both present competing, effortful information, the system must allocate priority quickly. If it can’t, control networks ramp suppression broadly, perceptual throughput drops, and reasoning/absorption stalls. Outwardly, that looks like zoning out. Neurophysiologically, it’s a protective bottleneck—the brain declines to process ambiguous or lower-priority channels to preserve stability in the one it thinks is most mission-critical.

Practical implications

• Dense slides plus fast speech is a failure-prone combination; one channel will lose.

• Visual task difficulty can render people briefly “deaf” to even salient sounds (alarms, names).

• Training should explicitly alternate which modality is prioritized and build flexible suppression of the other—without collapsing overall performance.

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How Squirrel CHASER Trains Multimodal Control

The Squirrel CHASER app is designed to replicate the kind of sensory competition people face every day audio and visual competition. Squirrel Chaser intentionally creates multimodal competition.  Built on principles inspired by the Stroop Effect, a classic test of selective attention. The app has been modernized to emphasize the simultaneous challenge of heavy visual and auditory input. Instead of simply naming incongruent colors, users must quickly discriminate and respond while visual and auditory tasks intentionally conflict. This forces the brain to practice prioritizing the right channel, suppressing irrelevant input, and shifting focus on demand. In doing so, Squirrel CHASER strengthens the neural networks responsible for multimodal filtering and cognitive flexibility.

The goal isn’t just accuracy on the test itself—it’s building resilience for the real world, where modern life demands constant negotiation between screens, sounds, and conversations. Over time, users report less frustration, fewer “shutdowns,” and greater ability to stay engaged when visual and auditory demands collide.

This isn’t willpower; it’s resource allocation across senses with real, measurable neural trade-offs. The skill to build is flexible, multi-modal control, and it can be trained deliberately.