Related Experiment Video
Updated: May 22, 2026
08:36
Constructing an Olfactometer for Rodent Olfactory Behavior Studies
Published on: April 11, 2025
Optophysiological analysis of associational circuits in the olfactory cortex
Akari Hagiwara1, Sumon K Pal, Tomokazu F Sato
1Department of Molecular and Cellular Biology, Center for Brain Science, Harvard University, Cambridge MA, USA.
Frontiers in Neural Circuits
|April 25, 2012
Summary
The anterior piriform cortex (aPC) has strong connections from the olfactory nucleus, while the posterior piriform cortex (pPC) connects densely to the aPC. This reveals distinct roles in odor processing.
Area of Science:
- Neuroscience
- Olfactory system research
- Cortical circuitry
Background:
- Olfactory cortical areas receive input from the olfactory bulb and have associational connections.
- Classical anatomical methods have primarily studied these connections.
- Functional properties of these circuits remain less understood.
Purpose of the Study:
- To investigate the functional properties of associational connections in the anterior piriform cortex (aPC) and posterior piriform cortex (pPC).
- To elucidate the distinct roles of aPC and pPC in olfactory processing circuits.
Main Methods:
- Utilized optophysiological methods to study functional connectivity.
- Examined connections between the anterior olfactory nucleus (AON), aPC, and pPC.
Main Results:
- The aPC receives dense functional input from the AON.
- Local recurrent connectivity in the aPC is sparse and weak.
- The pPC receives negligible input from the AON but dense connections from the aPC.
- The pPC exhibits denser local recurrent connections than the aPC.
- Functional connections from pPC to aPC are negligible.
Conclusions:
- The findings suggest a sensory role for the aPC in odor processing.
- The study provides a circuit basis for an associative role for the pPC in olfactory processing.
Keywords:
anterior olfactory nucleuscalcium imagingchannelrhodopsin-2odor processingpiriform cortexrecurrent connectionMore Related Videos
10:16Perforated Patch-clamp Recording of Mouse Olfactory Sensory Neurons in Intact Neuroepithelium: Functional Analysis of Neurons Expressing an Identified Odorant Receptor
Published on: July 13, 2015
09:51Analyzing Responses of Mouse Olfactory Sensory Neurons Using the Air-phase Electroolfactogram Recording
Published on: March 2, 2010
Related Concept Videos
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...
01:20Physiology 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...
01:14Motor and Sensory Areas of the Cortex
The cerebral cortex, the brain's outermost layer, is pivotal in processing complex cognitive tasks, emotions, and various sensory inputs and executing voluntary motor activities. This intricate structure is divided into three primary functional areas: the motor areas, sensory areas, and association areas.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
01:21Association Areas of the Cortex
Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision-making. Some key association areas include the following:
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
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...
01:23Somatosensory, Motor, and Association Cortex
The somatosensory cortex in the parietal lobes is crucial for interpreting sensory data such as touch, temperature, and proprioception. The somatosensory cortex, situated in the parietal lobes, plays a vital role in interpreting sensory information like touch, temperature, and proprioception—awareness of body position. This specialized brain region features an organized structure wherein neurons at the top primarily process sensations originating from the lower body. In contrast, those at the...