The neurobiology of splitbrain crayfish


  • Baltazar Barrera-Mera Department of Physiology, UNAM, CDM, Mexico
  • Juan José Granados-Romero Department of Surgery, Faculty of Medicine, UNAM, CDM, Mexico
  • José Juan Vargas-Morales Department of Physiology, Faculty of Medicine, UNAM, CDM, Mexico
  • Elvira Barrera-Calva Department of Physiology, UNAM, CDM, Mexico
  • Rodrigo Banegas-Ruiz Department of Traumatology, Rehabilitation Hospital, Luis Guillermo Ibarra, Ibarra
  • Emilio Pérez Ortega Department of Physiology, UNAM, CDM, Mexico
  • José Ángel Barajas-Colón Department of Angiology and Vascular Surgery, CMNSXXI, CDMX, Mexico
  • Francisco Fabian Gómez-Mendoza Department of Hand Surgery, Central Military Hospital, CDMX, Mexico
  • Carlos Rubén Baca-Domínguez Department of Hand Surgery and Microsurgery, Rehabilitation Hospital, Luis Guillermo Ibarra Ibarra, CDMX, Mexico
  • Yuri Jiménez Caprielova Department of Surgery, Angeles Villahermosa Hospital, Mexico
  • Román Alberto de la Rosa Llergo Department of Physiology, UNAM, CDM, Mexico
  • Rodrigo Mendoza-Aceves Department of Anesthesiology, Angeles del Pedregal Hospital, CDMX, Mexico
  • Ana Lilia Abundez-Pliego Department of Surgery, PEMEX General Hospital, Ciudad del Carmen, Mexico
  • Karen Uriarte-Ruiz Department of Physiology, UNAM, CDM, Mexico
  • Mariana del Carmen Radilla-Flores Department of Plastic Surgery, CENIAQ, CDMX, Mexico
  • Nelson Niels Espinosa-Queb Department of Plastic Surgery, CENIAQ, CDMX, Mexico
  • Alejandro Ángel Corona Figueroa Department of Plastic Surgery, CENIAQ, CDMX, Mexico
  • Bruno Andrés Salazar-Trujillo Department of Plastic Surgery, CENIAQ, CDMX, Mexico
  • Alan I. Valderrama-Treviño Department of Surgery, Central North Hospital PEMEX, CDMX, Mexico



Circadian rhythm, Electroretinography, Ganglia / physiology, Crayfish brain, Splitbrain crayfish, Circadian pacemakers


Background: They crayfish brain is segmented into two symmetrical hemiganglia. Normally both hemiganglia are in direct communication through a series of well-defined neural bridges that cross de midline to form reciprocal cross connections.

Methods: An original study was carried out in the Department of Physiology of the Faculty of Medicine, UNAM during the period from August 2019 to August 2020. 13 Crayfish Procambarus clarkii weighing between 1g to 30g were used. Each eyestalk of the animals was tied to a displacement transducer coupled with a polygraph so that optomotor or electrical activity was bilaterally recorded. The separation of the right from the left hemiganglia from the cerebral or supraesophageal ganglion was performed with a sagittal section, splitbrain (SB).

Results: The normal photo motor reflex in crayfish eye is measured as a gradual decrease in the ERG amplitude. During tactile stimulation, the visual activation of both eyestalks in normal crayfish leads to a highly regular bilateral activity. The regular activity can only be altered by disturbing the mechanoreceptors located in the shell surrounding the eyestalks.

Conclusions: The procedure presented in this article provides unique characteristics for the study of the nervous system such as a detailed response of the bilateral optomotor reflex.


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How to Cite

Barrera-Mera, B., Granados-Romero, J. J., Vargas-Morales, J. J., Barrera-Calva, E., Banegas-Ruiz, R., Pérez Ortega, E., Barajas-Colón, J. Ángel, Gómez-Mendoza, F. F., Baca-Domínguez, C. R., Caprielova, Y. J., de la Rosa Llergo, R. A., Mendoza-Aceves, R., Abundez-Pliego, A. L., Uriarte-Ruiz, K., Radilla-Flores, M. del C., Espinosa-Queb, N. N., Corona Figueroa, A. Ángel, Salazar-Trujillo, B. A., & Valderrama-Treviño, A. I. (2021). The neurobiology of splitbrain crayfish. International Journal of Research in Medical Sciences, 9(5), 1276–1280.



Original Research Articles