Adults can be trained to acquire synesthetic experiences

Area of Science:

• Cognitive Neuroscience
• Psychology
• Neuroscience of Learning

Background:

• Synesthesia, the experience of one sense triggering another, is typically viewed as congenital.
• An alternative theory suggests synesthesia may arise from repeated perceptual associations during development.

Purpose of the Study:

• To investigate if associative learning can induce synesthesia-like experiences in adults.
• To explore the potential of extensive training to shape perceptual experiences.

Main Methods:

• Non-synesthetic adults underwent a rigorous training program focused on 13 specific letter-color associations.
• Training involved adaptive memory and reading tasks to reinforce these associations.
• Behavioral and physiological markers of grapheme-color synesthesia were assessed post-training.

Main Results:

• Participants demonstrated behavioral and physiological indicators consistent with grapheme-color synesthesia.
• A majority reported experiencing colors for achromatic letters, both in and out of laboratory settings.
• These acquired experiences mimicked those typically associated with genuine synesthetes.

Conclusions:

• The findings support developmental theories of synesthesia, proposing that learning can play a significant role.
• This research highlights the capacity for new learning to modify perceptual experiences, even in adulthood.
• It suggests that synesthetic experiences may not always be congenital but can be acquired through associative learning.