Papez circuit
Overview
Described by James Papez
in 1937, the Papez circuit of the brain
is one of the major pathways of the limbic system
and is chiefly involved in the cortical
control of emotion
. The Papez circuit plays a role in storing memory.
Papez discovered the circuit after injecting rabies
virus into a cat's hippocampus
and monitoring its progression through the brain. The initial pathway was described as follows:
Since then, new findings in neuroanatomy
and brain function by Paul D.
James Papez
James Papez was an American neuroanatomist. Papez received his MD from the University of Minnesota College of Medicine and Surgery. He is most famous for his 1937 description of the Papez circuit which is a neural pathway in the brain thought to be involved in the cortical control of emotion...
in 1937, the Papez circuit of the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
is one of the major pathways of the limbic system
Limbic system
The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...
and is chiefly involved in the cortical
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
control of emotion
Emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...
. The Papez circuit plays a role in storing memory.
Papez discovered the circuit after injecting rabies
Rabies
Rabies is a viral disease that causes acute encephalitis in warm-blooded animals. It is zoonotic , most commonly by a bite from an infected animal. For a human, rabies is almost invariably fatal if post-exposure prophylaxis is not administered prior to the onset of severe symptoms...
virus into a cat's hippocampus
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
and monitoring its progression through the brain. The initial pathway was described as follows:
- Hippocampal formationHippocampal formationThe hippocampal formation is a compound structure in the medial temporal lobe of the brain. There is currently no consensus concerning which brain regions are encompassed by the term, with some authors defining it as the dentate gyrus, the hippocampus proper and the subiculum; and others including...
(SubiculumSubiculumThe subiculum is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 subfield of the hippocampus proper.-Paths:...
) → fornix → mammillary bodies - Mammillary bodies → mammillothalamic tractMammillothalamic tractThe mammillothalamic fasciculus arises from cells in both the medial and lateral nuclei of the mammillary body and by fibers that are directly continued from the fornix.The Mammillothalamic fasciculus then connects the mammillary body to the dorsal tegmental nuclei, the ventral...
→ anterior thalamic nucleus - Anterior thalamic nucleus → genu of the internal capsuleInternal capsuleThe internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. The internal capsule contains both ascending and descending axons....
→ cingulate gyrus - Cingulate gyrus → cingulum → parahippocampal gyrusParahippocampal gyrusThe parahippocampal gyrus is a grey matter cortical region of the brain that surrounds the hippocampus. This region plays an important role in memory encoding and retrieval....
- Parahippocampal gyrusParahippocampal gyrusThe parahippocampal gyrus is a grey matter cortical region of the brain that surrounds the hippocampus. This region plays an important role in memory encoding and retrieval....
→ entorhinal cortexEntorhinal cortexThe entorhinal cortex is located in the medial temporal lobe and functions as a hub in a widespread network for memory and navigation. The EC is the main interface between the hippocampus and neocortex...
→ perforant pathway → hippocampusHippocampusThe hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
.
Since then, new findings in neuroanatomy
Neuroanatomy
Neuroanatomy is the study of the anatomy and organization of the nervous system. In contrast to animals with radial symmetry, whose nervous system consists of a distributed network of cells, animals with bilateral symmetry have segregated, defined nervous systems, and thus we can begin to speak of...
and brain function by Paul D.
Unanswered Questions
