What are the regions of the hippocampus?

Anatomical terms of neuroanatomy The hippocampus proper refers to the actual structure of the hippocampus which is made up of three regions or subfields. The subfields CA1, CA2, and CA3 use the initials of cornu Ammonis, an earlier name of the hippocampus.

Why does episodic memory need the CA3 region of the hippocampus?

In this paper I also show that the primate hippocampus including CA3 has a special representation of space that makes it particularly appropriate for episodic memory in primates including humans, for it is a representation of space “out there.” This enables memories to be formed of what one has seen at a particular …

Is the CA2 part of 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.

Why is it called the hippocampus?

hippocampus, region of the brain that is associated primarily with memory. The name hippocampus is derived from the Greek hippokampus (hippos, meaning “horse,” and kampos, meaning “sea monster”), since the structure’s shape resembles that of a sea horse.

Is hippocampus white or gray matter?

The hippocampal body (corpus hippocampi) consists of the gray matter of the cornu ammonis, rolled into the dentate gyrus including the fascia dentata. It includes the histologically defined regions CA1–4.

What are CA 1 neurons?

Although hippocampal cornu ammonis (CA1) neurons in rodents play a pivotal role in the processing of hippocampus-dependent memory, the contribution of CA1 neurons in the human hippocampus to autobiographical memory and autonoetic consciousness remains elusive because of the rareness of a human model (10).

Is the hippocampus in the midbrain?

The midbrain is the smallest region of the brain, and is located most centrally within the cranial cavity. Limbic System – the limbic system is often referred to as our “emotional brain”, or ‘childish brain’. It is found buried within the cerebrum and contains the thalamus, hypothalamus, amygdala and hippocampus.

What does CA3 mean?

CA3

Where is CA3?

The CA3 hippocampal region receives information from the entorhinal cortex either directly from the perforant path or indirectly from the dentate gyrus via the mossy fibers (MFs). According to their specific targets (principal/mossy cells or interneurons), MFs terminate with large boutons or small filopodial …

Is the hippocampus white or gray matter?

What does CA2 stand for?

Calcium ion

What is CA4 in the hippocampus?

One edge of the “U,” – CA4, is embedded into the backward-facing, flexed dentate gyrus. The hippocampus is described as having an anterior and posterior part (in primates) or a ventral and dorsal part in other animals. Both parts are of similar composition but belong to different neural circuits.

What is the CA3 region of the hippocampus?

The CA3 region of the hippocampus contains a large excitatory recurrent collateral network (where axons loop back to input fibres, or dendrites), which constitutes the largest input source to CA3.

What are the subregions of the hippocampus?

The hippocampal formation itself is composed of several subregions, which include the cornu ammonis (CA1–4), the dentate gyrus, and the subiculum. The subregions of the hippocampus are connected by two principal neural circuits: the trisynaptic circuit and the monosynaptic circuit.

What is the shape of the hippocampus?

The hippocampus, including the dentate gyrus, has the shape of a curved tube, which has been compared to a seahorse, and a ram’s horn (Cornu Ammonis). Its abbreviation CA is used in naming the hippocampal subfields: CA1, CA2, CA3, and CA4.