Chapter

Limbic System

Marco Catani and Michel Thiebaut de Schotten

in Atlas of Human Brain Connections

Published on behalf of Oxford University Press

Published in print March 2012 | ISBN: 9780199541164
Published online November 2012 | e-ISBN: 9780191753268 | DOI: http://dx.doi.org/10.1093/med/9780199541164.003.0130
Limbic System

Show Summary Details

Preview

The limbic system is a group of interconnected cortical and subcortical structures dedicated to linking visceral states and emotion to cognition and behaviour (Mesulam, 2000). The use of the term ‘limbic’ has changed over time. Initially introduced by Thomas Willis (1664) to designate a cortical border encircling the brainstem (limbus, Latin ‘border’) the term has been used in modern neuroscience to indicate a progressively increasing number of regions dedicated to a wide range of functions (Mega et al., 1997; Marshall and Magoun, 1998). Paul Broca (1878) held the view that ‘le grand lobe limbique’ was mainly an olfactory structure common to all mammalian brains, although he argued that its functions were not limited to olfaction. After Broca's publication the accumulation of experimental evidence from ablation studies in animals broadened the role of the limbic structures to include other aspects of behaviour such as controlling social interactions, regulating predatory behaviour (Brown and Schäfer, 1888), consolidating memories (Bechterew, 1900), and forming emotions (Cannon, 1927). Anatomical and physiological advancements in the field led Christfield Jakob (1906) and James Papez (1937) to formulate the first unified network model for linking action and perception to emotion (Figure 11.1). According to Papez, ‘emotion may arise in two ways: as a result of psychic activity and as consequence of hypothalamic activity’. The psychic activity enters the circuit (later named after Papez) through the hippocampus while visceral and somatic perceptions enter the circuit through the hypothalamus. Thus, according to Papez: Incitations of cortical origin would pass first to the hippocampal formation and then down by way of the fornix to the mammillary body. From this they would pass upward through the mammillo-thalamic tract, or the fasciculus of Vicq d'Azyr, to the anterior nuclei of the thalamus and thence by the medial thalamocortical radiation [or anterior thalamic projections] to the cortex of the gyrus cinguli […] The cortex of the cingular gyrus may be looked on as the receptive region for the experiencing of emotion as the result of impulses coming from the hypothalamic region […] Radiation of the emotive process from the gyrus cinguli to other regions in the cerebral cortex would add emotional coloring to psychic processes occurring elsewhere. (Papez, 1937)

A decade later, Paul Yakovlev (1948), independently from Papez, proposed that the orbitofrontal cortex, insula, amygdala, and anterior temporal lobe form a network underlying emotion and motivation. In two seminal papers published in 1949 and 1952, Paul D. MacLean crystallized previous works by incorporating both Papez and Yakovlev view into a model of the limbic system that has remained almost unchanged since (MacLean, 1949, 1952). MacLean concluded that the limbic cortex, together with the limbic subcortical structures, is a functionally integrated system interconnected by short- and long-range fibre bundles (Figure 11.1).

Chapter.  9282 words.  Illustrated.

Subjects: Neuroscience

Full text: subscription required

How to subscribe Recommend to my Librarian

Buy this work at Oxford University Press »

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.