The CA1, CA2, and CA3 regions are the principal pyramidal cell fields in the hippocampus (Figure 3) and are often the focus of research concerned with memory encoding and retrieval (McNaughton and Morris, 1987; Chevaleyre and Siegelbaum, 2010).
What are CA3 pyramidal neurons?
The CA3 and CA1 pyramidal neurons are the major principal cell types of the hippocampus proper. A smaller proportion of CA3 than CA1 cells displayed prominent place fields, but place fields of CA3 neurons were more compact, more stable, and carried more spatial information per spike than those of CA1 pyramidal cells.
Where do CA3 hippocampal cells terminate?
There are also a significant number of recurrent connections that terminate in CA3. Both the recurrent connections and the Schaffer collaterals terminate preferentially in the septal area in a dorsal direction from the originating cells. CA3 also sends a small set of output fibers to the lateral septum.
What does CA3 mean?
CA3
| Acronym | Definition |
|---|---|
| CA3 | Carbonic Anhydrase 3 (gene) |
What is CA2 hippocampus?
The hippocampal CA2 area of the brain displays unique properties and con- nectivity that may be linked to disease. CA2 pyramidal neurons play a crucial role in the formation of social memory.
Does the hippocampus have white matter?
Throughout the majority of its anterior to posterior extent, the hippocampus is enveloped on its superior surface by white matter emanating from within the hippocampus. These afferent myelinated fibers of the alveus and fimbria coat the hippocampus and contour its trajectory through the Medial Temporal Lobe.
What does CA1 mean?
The term “CA1” is the academic shorthand for Continual Assessment 1, a mode of formal assessment for most primary school students starting at the Primary 2 level.
What are the regions of the hippocampus?
The hippocampal formation consists of the dentate gyrus, subicular cortex, and Ammon’s horn, which is further divided into three regions—Cornu Ammonis 1 (CA1), 2 (CA2), and 3 (CA3; Fig.
What is the role of CA1?
Within the hippocampal memory system, CA1 neurons are critically involved the formation, consolidation, and retrieval of hippocampal-dependant memories. This finding suggests that hippocampal CA1 neurons might have an important long-term role in the retrieval of remote memories.
Where is the CA2 in the hippocampus?
The CA2 region (medium green) is located between the CA3 region (light green) and the CA1 region (dark green) and is an integral part of the hippocampal circuitry.
What is the function of CA1 in the hippocampal circuit?
CA1 is the first region of the hippocampal neural circuit, which outputs information to the V layer of the entorhinal cortex and to the subiculum. The CA1 region accepts input from the CA2 region and the CA3 region. The CA2 region sends temporal data, whereas the CA3 region sends spatial data.
Does CA3 stimulation cause BOLD responses in the hippocampus?
In fact, electrical stimulation of the CA3 region often causes BOLD responses, not only inside the hippocampus proper/subiculum, but also outside the hippocampal formation ( Moreno et al., 2015; Scherf and Angenstein, 2015, 2017 ).
Do CA3 pyramidal cells directly project to the entorhinal cortex?
As CA3 pyramidal cells do not directly project to the entorhinal cortex, any observed significant BOLD responses that occur outside the hippocampal formation should be generated by outgoing activity from principal cells in the CA3, CA1, and/or the subiculum, but not by a directly activated entorhinal cortex.
What happens to neurons in the CA3 region under stress?
Neurons of the hippocampal CA3 region exhibit a loss of dendritic spines, reduced dendritic branching, and impaired neurogenesis in response to stress exposure.14
