Fictive behavior explained

Fictive behavior is when an organism’s sensory input and/or motor output is silenced for physiological experiments.

Processes

A fictive preparation of the nervous system is achieved by surgical removal or chemical fixation, to observe behavior in response to experimental stimuli.[1] [2] Fixation allows for observation of target areas without interference from undesired neural signals or behavioral movement, which leads to more precise data collection. However, fictive behavior does not entirely resemble in vivo behavior because the true system has been altered. In some cases, surgery or measurement devices lessen the intensity of cellular signals.[1] [3] The goal of measuring localized behavior is to discover and or understand the circuitry further. The type of neural circuitry that is most commonly observed with fictive behavior are those that underlie rhythmic-behavior patterns.[4] [1] [5]

Here is an example of how fictive feeding behavior is observed in a great pond snail (Lymnaea stagnalis). The lip and tentacle areas are bisected and isolated, by removing all other peripheral nerves, but the lip/tentacle and buccal nerves remain connected to the cerebral ganglia. Now establishing the buccal nerve pathway as the only way for signals to pass back and forth to the cerebral ganglia, sucrose (the food stimuli) is introduced to the lip and tentacle areas while intracellular recordings are taken simultaneously. The recordings take place in a saline solution that keeps the system viable for the duration of the experiment.[5]

Notes and References

  1. 10.1016/S0960-9822(01)00581-4 . Central pattern generators and the control of rhythmic movements . Current Biology . 11 . 23 . R986–R996 . 2001 . Marder . Eve . Bucher . Dirk . 11728329 . free . 2001CBio...11.R986M .
  2. 9319973 . Ontogeny of central chemoreception during fictive gill and lung ventilation in an in vitro brainstem preparation of Rana catesbeiana . Journal of Experimental Biology . 200 . 15 . 2063–2072 . January 1997 . Remmers . J. . Gdovin . M. . Torgerson . C. . 10.1242/jeb.200.15.2063 .
  3. 10.1113/jphysiol.1995.sp021067 . 8847642 . 1156774 . Experimentally derived model for the locomotor pattern generator in the Xenopus embryo . The Journal of Physiology . 489 . 2 . 489–510 . 1995 . Dale . N. .
  4. 10.1152/jn.1999.82.2.1074 . 10444700 . Fictive Rhythmic Motor Patterns Induced by NMDA in an In Vitro Brain Stem–Spinal Cord Preparation From an Adult Urodele . Journal of Neurophysiology . 82 . 2 . 1074–1077 . 1999 . Delvolvé . Isabelle . Branchereau . Pascal . Dubuc . Réjean . Cabelguen . Jean-Marie . free .
  5. 7472516 . Behavioral role for nitric oxide in chemosensory activation of feeding in a mollusc . The Journal of Neuroscience . 15 . 11 . 7653–7664 . 6578070 . 10.1523/JNEUROSCI.15-11-07653.1995 . 1995 . Elphick . MR . Kemenes . G. . Staras . K. . O'Shea . M. . free .