Summary: Some blind people develop an impressive ability called echolocation, using sharp mouth clicks and the returning echoes to sense objects and navigate. A recent study has mapped how the human brain accumulates and processes those echoes to build a spatial representation of the environment.
Researchers compared expert blind echolocators with sighted participants tested in total darkness. They found that the brain does more than simply detect a single echo: it progressively integrates information over a sequence of clicks. Each successive click adds detail, allowing experts to form a high-resolution, real-time internal map of nearby objects.
Key Facts
- Expert precision: Four blind expert echolocators performed substantially better than 21 sighted participants at locating objects in a darkened room.
- Build-up effect: Neural responses strengthened with each additional click. The more clicks an expert produced, the more precise their sound-based spatial judgments became.
- Information summation: Lead researcher Haydee Garcia-Lazaro reports the brain appears to sum information across clicks, accumulating evidence about an object’s location.
- Behavioral correlation: Object-location accuracy improved linearly with the number of self-generated mouth clicks, showing that echolocation is an active, iterative process.
- Training potential: The findings suggest echolocation skills could be taught, since specific neural processes for spatial representation are engaged during the task.
Source: SfN
What the study examined
Published in eNeuro, the study by Haydee Garcia-Lazaro and Santani Teng at the Smith–Kettlewell Eye Research Institute examined how the human brain turns returning echoes from mouth clicks into spatial representations. Using behavioral testing and EEG, the team analyzed how repeated echoes are combined over time and how neural activity relates to performance.
In behavioral tests, the four blind expert echolocators identified object locations with much higher accuracy than 21 sighted participants tested in darkness. For experts, localization thresholds improved as the number of clicks increased, consistent with the idea that spatial information is integrated cumulatively across repeated acoustic samples.
EEG recordings showed that neural signals could reliably discriminate echo laterality from the very first click, and these neural signatures correlated with overall localization ability. As successive clicks arrived, the neural responses evolved in a way that reflected the click’s position in the sequence, indicating an unfolding accumulation process rather than a simple repetition effect.
Modeling at the trial level allowed the researchers to distinguish accumulation-style decision policies from alternative explanations based on repetition alone, revealing individual differences among the expert echolocators in how they read out accumulated evidence.
Garcia-Lazaro summarized the findings by noting that, in skilled echolocators, the brain appears to accumulate information across clicks to build a robust representation of an object’s location. The study demonstrates how repeated auditory samples are progressively integrated into coherent spatial maps even in the absence of vision.
Key Questions Answered:
A: In a functional sense, yes. Although echolocation relies on sound, the brain often recruits visual cortical areas to process spatial information. The study indicates that experts build a kind of 3D model from echoes—enough to infer distance, size, and even surface properties.
A: Sighted people can show a latent capacity for echo-based spatial sensing but are typically far less accurate. Long-term practice and neural plasticity appear to tune the brains of expert echolocators to prioritize subtle echo cues, whereas sighted brains generally rely on visual input.
A: The researchers are optimistic. Because the study identifies a neural accumulation process that supports echolocation, it points to the possibility of training programs that teach people—whether blind or sighted—to attend to and integrate echoes across clicks.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The journal paper was reviewed in full by staff.
- Additional context was added by editorial staff.
About this visual and auditory neuroscience research news
Author: SfN Media ([email protected])
Source: SfN
Contact: SfN Media – SfN
Image: The image is credited to Neuroscience News
Original Research: Closed access.
Title: Neural and Behavioral Correlates of Evidence Accumulation in Human Click-Based Echolocation
Authors: Haydée G García-Lázaro and Santani Teng. eNeuro
DOI: 10.1523/ENEURO.0342-25.2026
Abstract
Neural and Behavioral Correlates of Evidence Accumulation in Human Click-Based Echolocation
Echolocation allows blind individuals to sense and navigate their surroundings by producing mouth clicks and interpreting the returning echoes. While expert blind echolocators demonstrate impressive spatial precision, how spatial echo-acoustic cues are combined across repeated samples has been less clear.
This study examined the temporal dynamics of spatial information processing in human click-based echolocation using electroencephalography (EEG). Participants included blind expert echolocators (n = 4, all male) and novice sighted participants (n = 21, 12 male). Virtual spatialized echoes, derived from realistic synthesized mouth clicks, were presented in trains ranging from 2 to 11 clicks.
Behaviorally, blind experts outperformed sighted controls in spatial localization. For experts, localization thresholds improved as click counts increased, consistent with cumulative integration of spatial information across repeated samples. EEG decoding demonstrated reliable discrimination of echo laterality from the first click, and this neural discrimination correlated with overall localization performance.
Across successive clicks, neural responses changed systematically, reflecting position-dependent dynamics within the sequence. Trial-level EEG modeling distinguished accumulation-consistent decision strategies from repetition-based alternatives, revealing individual differences in how experts read out accumulated evidence.
These results offer a detailed account of the temporal neural dynamics that support human click-based echolocation and link those dynamics directly to behavioral performance across multiple samples. They show that, in successful expert echolocators, successive echoes are progressively integrated into coherent spatial representations, demonstrating adaptive sensory processing in the absence of vision.