Touch can produce detailed, lasting memories

November 27, 2018

Exploring objects through touch can generate detailed, durable memories for those objects, even when we don't intend to memorize the object's details, according to findings published in Psychological Science, a journal of the Association for Psychological Science.

"An especially interesting finding was that participants were able to visually identify an object they had never seen but only touched one week before without the intention of memorization," says researcher Fabian Hutmacher of the University of Regensburg. "This is even more remarkable as the competing objects in the recognition test belonged to the same basic-level category - that is, the previously presented object was only identifiable based on subtle touch-based details but not on much more salient visual details."

"The study challenges existing cognitive and neural models of memory storage and retrieval, as these models seem to be unable to account for the large amount of stored information," Hutmacher adds.

Compared with visual information, relatively little is known about long-term memory for information sensed through other modalities. Hutmacher and coauthor Christof Kuhbandner decided to focus specifically on haptic, or touch-based, experiences.

In one experiment, participants wore a blindfold as they explored 168 everyday objects, such as a pen, for 10 seconds each. The researchers told the participants they would be tested on the objects later, so they should pay close attention to the texture, shape, and weight of each object. The participants, still blindfolded, completed a haptic memory test for half of the objects immediately after exploring them. They held each object they had explored and a similar novel object that was distinguishable only by subtle details - their task was to indicate which object they had explored before. They completed the same test with the other half of the objects 1 week later.

Participants showed almost perfect recall on the test that followed the exploration period, correctly identifying the object they had explored 94% of the time. Remarkably, participants still showed robust memory for the original objects 1 week later, with 84% accuracy.

But would they still remember objects so well if they weren't intentionally memorizing them? And could objects that were explored by touch be recognized via a different sensory modality?

In a second experiment, a new group of participants explored the same 168 objects without knowing they would be tested on them. Instead, the experimenters said that they were investigating aesthetic judgments, and they asked the participants to rate the pleasantness of each object based on texture, shape, and weight.

Participants returned 1 week later for a surprise memory test, completing a blindfolded touch-based recognition task for half of the objects. For the rest of the objects, they completed a visual recognition task, in which they saw the original object and a similar object placed on a table, and indicated which one they previously explored. After each trial, the participants also reported if they answered based on recalling details of their touch-based exploration, feeling a vague familiarity, or simply guessing.

Again, the results showed that participants remembered the objects with high accuracy. In the blindfolded test, participants answered correctly on 79% of the trials. In the cross-modal visual test, participants identified the correct object 73% of the time.

For both tests, participants were most accurate for objects they said they recalled details for, moderately accurate for objects that seemed vaguely familiar, and least accurate for those they guessed on. Notably, participants showed better-than-chance recognition even when they reported that they had guessed.

The fact that participants could recognize objects across sensory modalities is intriguing given that the familiar and novel objects only differed on subtle details that would have to be distinguished on the basis of haptic experiences.

"These results suggest that the human mind effortlessly and automatically stores detailed and durable representations of a vast amount of perceptual experiences, including haptic ones," says Hutmacher. "We want to explore the idea that storing such a vast amount of information may in fact be functional as it may guide our behavior and contribute to its fine-tuning without being accompanied by conscious experience."
All data and materials have been made publicly available via the Open Science Framework (OSF). The design and analysis plans for Experiment 2 were preregistered at the OSF. The complete Open Practices Disclosure for this article is available online. This article has received the badges for Open Data, Open Materials, and Preregistration.

For more information about this study, please contact: Fabian Hutmacher at

The article abstract is available online at

The APS journal Psychological Science is the highest ranked empirical journal in psychology. For a copy of the article "Long-Term Memory for Haptically Explored Objects: Fidelity, Durability, Incidental Encoding, and Cross-Modal Transfer" and access to other Psychological Science research findings, please contact Anna Mikulak at 202-293-9300 or

Association for Psychological Science

Related Touch Articles from Brightsurf:

Staying in touch!
New mechanism regulating the adhesion of cells to the surrounding extracellular support structures discovered at the University of Konstanz - New options for the treatment of inflammatory processes and tumour metastasis

Goby fins have fingertip touch sensitivity
Primates are renowned for their delicate sense of touch, but now a series of experiments by scientists from The University of Chicago, USA, published in Journal of Experimental Biology reveal that the fins of round gobies are as touch sensitive as primate fingertips.

Touch and taste? It's all in the tentacles
Scientists identified a novel family of sensors in the first layer of cells inside the suction cups that have adapted to react and detect molecules that don't dissolve well in water.

How octopus suckers "taste by touch"
Imagine if you could taste something simply by touching it.

New glove-like device mimics sense of touch
UNSW engineers have invented a soft wearable device which simulates the sense of touch and has wide potential for medical, industrial and entertainment applications.

Star-cells "shine" to make sense of touch
The IBS research group reports a rather surprise finding as to how GABA works to control the tactile sense.

Scientists discover a new connection between the eyes and touch
Tiny eye movements can be used as an index of humans' ability to anticipate relevant information in the environment independent of the information's sensory modality.

A soft touch for robotic hardware
Robots can be made from soft materials, but the flexibility of such robots is limited by the inclusion of rigid sensors necessary for their control.

Gentle touch loses its pleasure in migraine patients
Psychophysical data suggest that migraine patients may have abnormal affective aspects of sensorial functioning, by showing reduced sensation of pleasure associated with touch.

Approaching the perception of touch in the brain
More than ten percent of the cerebral cortex are involved in processing information about our sense of touch -- a larger area than previously thought.

Read More: Touch News and Touch Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to