Experimental Brain Research

, Volume 64, Issue 3, pp 515–526 | Cite as

A description of the amygdalo-hippocampal interconnections in the macaque monkey

  • J. P. Aggleton


The interconnections between the amygdala and the hippocampal formation were investigated in the macaque monkey using anterograde tracers. The hippocampal inputs to the amygdala arose from the subicular and entorhinal cortices and passed through the angular bundle to terminate principally in the medial basal and lateral basal nuclei, with lighter termination in the lateral nucleus, the periamygdaloid cortex, and the cortical-transition area. The majority of these amygdaloid inputs arose from the rostral hippocampal formation although there was equivocal evidence of an additional projection from the caudal hippocampus to the central nucleus. Projections arose from many of the amygdaloid nuclei to terminate in the molecular layer of the amygdalo-hippocampal area and the adjacent stratum moleculare of the uncal portion of the hippocampus. The accessory basal, lateral basal, and medial basal nuclei also projected to the most rostral portions of the stratum moleculare of fields CA1–3, the heaviest termination occurring in field CA3. Additional projections from the basal nuclei terminated in the prosubiculum, presubiculum, and para-subiculum. The heaviest entorhinal inputs arose from the accessory basal and lateral nuclei and terminated in layers I, II, and III of areas 28b, 28i, and the prorhinal cortex. The major amygdaloid input to the perirhinal cortex arose from the lateral basal nucleus.

Key words

Amygdala Hippocampus Neuro-anatomy Monkey 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Adey WR, Meyer M (1952) Hippocampal and hypothalamic connexions of the temporal lobe of the monkey. Brain 75: 358–384PubMedCrossRefGoogle Scholar
  2. Aggleton JP, Burton MJ, Passingham RE (1980) Cortical and subcortical afferents to the amygdala of the rhesus monkey (Macaca mulatta). Brain Res 190: 347–368PubMedCrossRefGoogle Scholar
  3. Aggleton JP, Desimone R, Mishkin M (1986) The origin, course, and termination of the hippocampo-thalamic projections in the macaque. J Comp Neurol 243: 409–422PubMedCrossRefGoogle Scholar
  4. Aggleton JP, Mishkin M (1984) Projections of the amygdala to the thalamus in the cynomolgus monkey. J Comp Neurol 222: 56–68PubMedCrossRefGoogle Scholar
  5. Aggleton JP, Mishkin M (1985) Mamillary-body lesions and visual recognition in monkeys. Exp Brain Res 58: 190–197PubMedCrossRefGoogle Scholar
  6. Amaral DG, Cowan WM (1980) Subcortical afferents to the hippocampal formation in the monkey. J Comp Neurol 189: 573–591PubMedCrossRefGoogle Scholar
  7. Amaral DG, Veazey RB, Cowan WM (1982) Some observations on hypothalamo-amygdaloid connections in the monkey. Brain Res 252: 13–27PubMedCrossRefGoogle Scholar
  8. Bakst I, Amaral DG (1984) The distribution of acetylcholinesterase in the hippocampal formation of the monkey. J Comp Neurol 225: 344–372PubMedCrossRefGoogle Scholar
  9. Brierley JB (1977) Neuropathology of amnesic states. In: Whitty CWM, Zangwill OL (eds) Amnesia. Butterworths, London, pp 199–223Google Scholar
  10. Brodman K (1909) Vergleichende Lokalisationslehre der Großhirnrinde in ihren Prinzipien dargestellt auf Grund des Zellenbaues. Barth, Leipzig, pp 1–324Google Scholar
  11. Crosby EC, Humphrey T (1941) Studies of the vertebrate telencephalon. II. The nuclear pattern of the anterior olfactory nucleus, tuberculum olfactorium and the amygdaloid complex in adult man. J Comp Neurol 74: 309–352CrossRefGoogle Scholar
  12. Hilpert P (1928) Der Mandelkern des Menschen. I. Cytoarchitektonik und Faserverbindungen. J Psychol Neurol 36: 44–74Google Scholar
  13. Jimenez-Castellanos J (1949) The amygdaloid complex in the monkey studied by reconstructional methods. J Comp Neurol 91: 507–526PubMedCrossRefGoogle Scholar
  14. Johnston JB (1923) Further contributions to the study of the evolution of the forebrain. J Comp Neurol 35: 337–481CrossRefGoogle Scholar
  15. Krettek JE, Price JL (1977) Projections from the amygdaloid complex and adjacent olfactory structures to the entorhinal cortex and to the subiculum in the rat and cat. J Comp Neurol 172: 723–752PubMedCrossRefGoogle Scholar
  16. Lorente de Nó R (1934) Studies on the structure of the cerebral cortex. II. Continuation of the study of the ammonic system. J Psychol Neurol 46: 113–177Google Scholar
  17. Mehler WR (1980) Subcortical afferent connections of the amygdala in the monkey. J Comp Neurol 190: 733–762PubMedCrossRefGoogle Scholar
  18. Mishkin M (1982) A memory system in the monkey. Philos Trans R Soc B298: 85–95Google Scholar
  19. Morrison F, Poletti CE (1980) Hippocampal influence on amygdala unit activity in awake squirrel monkeys. Brain Res 192: 353–369PubMedCrossRefGoogle Scholar
  20. Murray EA, Mishkin M (1986) Visual recognition in monkeys following rhinal cortical ablations combined with either amygdalectomy or hippocampectomy. J Neurosci (in press)Google Scholar
  21. Nauta WJM (1961) Fibre degeneration following lesions of the amygdaloid complex in the monkey. J Anat (Lond) 95: 515–530Google Scholar
  22. Ottersen OP (1982) Connections of the amygdala in the rat. IV. Corticoamygdaloid and intramygdaloid connections as studied with axonal transport of horseradish peroxidase. J Comp Neurol 205: 30–48PubMedCrossRefGoogle Scholar
  23. Poletti CE, Creswell G (1977) Fornix system efferent projections in the squirrel monkey: an experimental degeneration study. J Comp Neurol 175: 101–128PubMedCrossRefGoogle Scholar
  24. Poletti CE, Sujatanond M (1980) Evidence for a second hippocampal efferent pathway to hypothalamus and basal forebrain comparable to fornix system: a unit study in the awake monkey. J Neurophysiol 44: 514–531PubMedGoogle Scholar
  25. Rosene DL, Van Hoesen GW (1977) Hippocampal efferents reach widespread areas of cerebral cortex and amygdala in the rhesus monkey. Science 198: 315–317PubMedCrossRefGoogle Scholar
  26. Russchen FT (1982) Amygdalopetal projections in the cat. I. Cortical afferent connections. A study with retrograde and anterograde tracing techniques. J Comp Neurol 206: 159–179PubMedCrossRefGoogle Scholar
  27. Sarter M, Markowitsch HJ (1985) The amygdala's role in human mnemonic processing. Cortex 21: 7–24PubMedGoogle Scholar
  28. Saunders RC, Rosene D (1986) A comparison of the amygdala and the hippocampal formation in the rhesus monkey. I. Convergence in the entorhinal, prorhinal and perirhinal cortices. J Comp Neurol (in press)Google Scholar
  29. Valenstein ES, Nauta WJH (1957) A comparison of the distribution of the fornix system in the rat, guinea pig, cat and monkey. J Comp Neurol 113: 337–363CrossRefGoogle Scholar
  30. Van Hoesen GW, Pandya DN (1975) Some connections of the entorhinal (area 28) and perirhinal cortices of the rhesus monkey. III. Efferent connections. Brain Res 95: 39–59PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • J. P. Aggleton
    • 1
  1. 1.Laboratory of NeuropsychologyNational Institute of Mental HealthRockville Pike, BethesdaUSA

Personalised recommendations