Skip to content
PaperFren

Neurocognitive aging

How the aging brain learns to see shapes in clutter

Mayhew SD, Kourtzi Z · Frontiers in human neuroscience · 2013

Open access · cc by · source: Europe PMC

While older and younger adults improve equally at identifying visual shapes in noisy backgrounds, they rely on different brain pathways, with older adults relying more on attention networks in the parietal lobe rather than frontal decision-making areas.

Key findings

Both the young and older groups showed similar improvements in their behavioral ability to detect the shapes in clutter after training. However, the brain scans showed that these groups used different neural pathways. Young adults showed learning-related changes across an extended network of occipitotemporal, parietal, and frontal brain regions. In contrast, older adults showed learning-related changes that were concentrated almost entirely in parietal regions.

Methodology

The researchers trained ten young adults and ten older adults to identify radial or concentric circular patterns hidden in visual noise. This training took place over three sessions on consecutive days. To see how brain activity changed with this training, the researchers used functional MRI to scan the participants' brains. They also ran a control experiment with eight participants in each age group to see if brain changes persisted when participants performed an unrelated task.

Limitations

This study cannot prove that the parietal brain changes are the direct cause of the visual improvements in older adults, as fMRI measurements are correlational. The study was also limited by its small sample sizes of ten participants per group in the main experiment and eight participants per group in the control experiment. Because fMRI scans have poor temporal resolution, this design cannot separate fast sensory signals from slower cognitive processes. Additionally, the researchers had to adjust the response design for older adults to ensure motor speed differences did not confound the results.

How this study connects

Role on claims

Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.

  • SupportsHemodynamic Responseconcept

    Due to the slow onset and decay of the hemodynamic response, standard fMRI designs suffer from poor temporal resolution, making it difficult to separate rapid sensory signals from slower cognitive processes.

    Evidence for the claim as stated.

  • SupportsHemodynamic Responseconcept

    Hemodynamic responses reveal that older and younger adults can recruit entirely different neural pathways to achieve identical behavioral improvements on visual tasks.

    Evidence for the claim as stated.

Related papers in this topic

Same topic cluster — not a recommendation engine.