Related Experiment Video
Updated: Jun 3, 2026
10:42
A Lateralized Odor Learning Model in Neonatal Rats for Dissecting Neural Circuitry Underpinning Memory Formation
Published on: August 18, 2014
Neural correlates of olfactory processing in congenital blindness.
R Kupers1, M Beaulieu-Lefebvre, F C Schneider
1Institute of Neuroscience and Pharmacology, Panum Institute, University of Copenhagen, Blegdamsvej 3B, 2300 Copenhagen, Denmark. ron@pet.rh.dk
Neuropsychologia
|April 5, 2011
Summary
Congenitally blind individuals show enhanced olfactory processing, with the occipital cortex recruited for smell. This highlights cross-modal plasticity in the brain when vision is absent from birth.
Area of Science:
- Neuroscience
- Sensory processing
- Neuroplasticity
Background:
- Congenital blindness leads to adaptive neuroplastic changes in tactile and auditory processing.
- Olfactory system plasticity is significant, and blind individuals often rely more on smell.
- Limited research exists on olfactory processing in the absence of vision.
Purpose of the Study:
- Investigate olfactory processing in congenitally blind individuals.
- Test the hypothesis of cross-modal changes in olfactory areas similar to other senses.
- Examine brain activity differences during odor detection between blind and sighted individuals.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used.
- Blood-oxygen-level-dependent (BOLD) signal changes were measured.
- Congenitally blind and blindfolded sighted control subjects performed an odor detection task.
Main Results:
- Congenitally blind subjects showed stronger activation in primary (amygdala) and secondary (orbitofrontal cortex, hippocampus) olfactory areas compared to controls.
- Widespread task-related activation was observed in the occipital cortex of blind participants, but not sighted participants.
- Olfactory stimuli preferentially accessed the occipital cortex in individuals blind from birth.
Conclusions:
- The visually deprived occipital cortex exhibits supramodal function, processing olfactory information in congenital blindness.
- This finding expands understanding of cross-modal plasticity beyond tactile and auditory senses.
- Olfactory processing is integrated into the occipital cortex in the absence of vision from birth.
More Related Videos
13:26Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography
Published on: August 11, 2016
08:33Olfactory Neurons Obtained through Nasal Biopsy Combined with Laser-Capture Microdissection: A Potential Approach to Study Treatment Response in Mental Disorders
Published on: December 4, 2014
Related Concept Videos
01:03Olfactory Receptors: Location and Structure
The process of olfaction, also known as the sense of smell, is a sophisticated chemical response system. The specialized sensory neurons that facilitate this process, known as olfactory receptor neurons, are situated in an upper segment of the nasal cavity, known as the olfactory epithelium. Olfactory sensory neurons are bipolar, with their dendrites extending from the epithelium's apex into the mucus that lines the nasal cavity. Airborne molecules, when inhaled, traverse the olfactory...
01:24Prosopagnosia
Prosopagnosia, also known as face blindness, is the inability to recognize faces. In severe cases, individuals with prosopagnosia may not recognize close family members, including parents and spouses, by their faces. For instance, someone with prosopagnosia might walk past their child in a crowd, only realizing their mistake upon noticing their child's distinctive backpack or favorite jacket. Prosopagnosia specifically impairs facial recognition, while the recognition of other objects or...
01:12Visual Agnosia
Visual agnosia is a condition characterized by the inability to recognize visually presented objects despite having normal vision. For instance, a person with visual agnosia can describe the shape and color of an object but cannot identify or name it. This impairment does not affect their visual field, acuity, color vision, brightness discrimination, language, or memory. An example of this condition in a social setting is someone at a dinner party asking for "that silver thing with a round end"...
01:20Physiology of Smell and Olfactory Pathway
Humans detect odors with the help of specialized cells located in the upper part of the nasal cavity, called olfactory receptor neurons (ORNs). ORNs possess hair-like structures called cilia, which are receptive to sensations from the inhaled air. When an odorant molecule binds to a specific receptor on the cell of the cilia, it leads to a series of events that ultimately cause the ORN to send electrical signals to the olfactory bulb in the brain through the olfactory nerves.
The olfactory...
The olfactory...
01:25Olfaction
The sense of smell is achieved through the activities of the olfactory system. It starts when an airborne odorant enters the nasal cavity and reaches olfactory epithelium (OE). The OE is protected by a thin layer of mucus, which also serves the purpose of dissolving more complex compounds into simpler chemical odorants. The size of the OE and the density of sensory neurons varies among species; in humans, the OE is only about 9-10 cm2.
The olfactory receptors are embedded in the cilia of the...
The olfactory receptors are embedded in the cilia of the...
01:24Vision
Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.