Gene Homer1: Reducing Brain ‘Noise’ May Improve Focus & Attention

Maintaining focus relies on the brain’s ability to filter out irrelevant information and quickly respond to important signals. This process is fundamental to daily life, impacting everything from work productivity to personal safety.

New research suggests that, rather than boosting neuronal activity, an approach that reduces background “noise” may support concentration. This finding offers a potentially new avenue for understanding and addressing attention-related challenges.

Attention disorders, such as ADHD (attention-deficit/hyperactivity disorder), arise when the brain struggles to quickly differentiate between truly important information and competing stimuli that divert attention – like surrounding sounds, notifications, visual movement, or intrusive thoughts.

Traditional Approaches Versus New Perspectives

Currently, most treatments for these disorders aim to stimulate the circuits involved in attention, particularly in the prefrontal cortex – a brain region heavily involved in attentional control – by increasing neuronal activity.

A study published December 24, 2025, in the journal Nature Neuroscience proposes a different direction: reducing background activity in the brain, which could support attention by diminishing the neuronal “noise” that interferes with processing relevant signals.

The research, conducted by a team led by scientists at the Laboratory of Neuronal Dynamics and Cognition at Rockefeller University, identified the Homer1 gene as a key element in this mechanism. Understanding the genetic factors influencing attention could lead to more targeted interventions.

In experiments with mice, decreasing the levels of two specific variants of the gene was associated with reduced brain activity and improved performance on attention tests.

Researchers noted that Homer1 wasn’t their initial focus. While the gene is well-known for its role in transmitting signals between neurons, and several proteins that interact with it have been linked in genetic studies to attention disorders, Homer1 itself hadn’t previously been highlighted as a major factor in attention.

To investigate a potential genetic link between variations in DNA and differences in attention, the team analyzed the genomes of nearly 200 mice from eight different parental lines, including those with a wild ancestry, to achieve a genetic diversity closer to that found in humans.

Genetic analysis revealed that mice performing best on attention tests had lower levels of the Homer1 gene in the prefrontal cortex, and differences in this DNA region accounted for nearly 20% of the variation in attention measured between the mice.

Further experiments showed that not all forms of Homer1 are involved equally: two variants, Homer1a and Ania3, stood out, with naturally lower levels of these variants in the prefrontal cortex consistently associated with better performance on attention tests.

The Importance of Development

Moreover, when researchers experimentally reduced these variants in adolescent mice, within a short developmental window, the effects were pronounced. The animals became faster and more accurate, and their performance was less affected by distracting stimuli in multiple behavioral tests.

The same genetic intervention in adult mice did not yield improvements, suggesting that Homer1 influences attention during a critical early stage of development.

A key surprise emerged when the team investigated how Homer1 affects nerve cells: decreasing Homer1 levels caused neurons in the prefrontal cortex to increase the number of GABA receptors (receptors for GABA, the brain’s primary inhibitory neurotransmitter – which the authors describe as the “brakes” of the nervous system).

According to the study, after Homer1 levels were reduced, neurons in the prefrontal cortex were less active “at baseline,” in the absence of a relevant signal. However, when important cues appeared, neuronal activity remained strong and well-directed, and responses became more precise and consistent.

Researchers had expected that mice with better attention would have a more generally “active” prefrontal cortex. Instead, they found that more attentive mice had less “background” activity in the prefrontal cortex. Their explanation is that reduced background activity means fewer parasitic signals, allowing the brain to respond more clearly and consistently when a relevant stimulus arises.

Conclusions and Perspectives for Treatments

The authors suggest that these results could support a different strategy for future treatments of attention disorders: rather than increasing neuronal activity with stimulants, reducing the background activity that generates “noise” and interferes with attentional stimuli could be pursued. This shift in approach could offer new hope for individuals struggling with attention-related challenges.

Researchers also note that Homer1 has been associated with conditions where differences in early sensory information processing are described, such as autism and schizophrenia, and they plan to continue investigating the genetic factors that influence attention.

Regarding potential treatments, the authors say that there is an area within the Homer1 gene involved in “splicing” (the process by which a gene can generate multiple variants of messenger RNA) that could be targeted with drugs. The idea would be to adjust Homer1 levels – and, consequently, the balance between useful signals and background “noise” in brain activity – for an effect of reducing neuronal background activity by targeting this area.