Forward Dendritic Spikes - Advancing Artificial Intelligence Through Biological Process Applications - page 56

as critical, are revealed by modeling as crucial for
determining the pattern of cell firing. A continu-
ous effort should be made to develop experimen-
tal procedures that facilitate the observation of
dendrites in intact preparations.
Obviously, disclosing the fine details of local
dendritic integration is a must. So far, dendrites
have been considered a black box. It is time to
recognize their extraordinary computational
capabilities, classify them, and describe their
physiological ranges. Knowing the computational
character that each channel and combination of
channels confer to dendrites will also help to
understand why have they been preserved in
evolution, and will also provide new mathemati-
cal tools that can be applied in artificial networks
and the real life.
An opening field of research addresses the
homeostatic mechanisms of cell activity. There
is not yet full awareness as to how the findings
in this area may condition future research and the
interpretation of data obtained so far. It may well
be that some neuronal mechanisms established by
past research are actually functioning only under
the extreme conditions for adequate observation,
i.e., activated by excessive perturbation of an
object of study that self-adapts to the presence
of our exploring devices/strategies.
An evident area of strong impact and fast de-
velopment in neuroscience is the use of realistic
mathematical models of single neurons. It not
only helps to understand experimental data, but
in cases like the examined here, it may advance
the possible mechanisms that operate in systems
that cannot be accessed experimentally. In the
future, simplified models should only be used to
explore the potential applications of basic neuronal
principles in artificial systems. Those aiming to
help physiologists must be detailed to the most
and thoroughly scrutinized for safe parameter
restriction.

ACkNOWLEDGMENT

This work was supported by grants BFU 2005/8917
from the Spanish Ministry of Science and Edu-
cation, S-SEM-0255-2006 from the Comunidad
Autónoma de Madrid, and I3/200620I186 from
the CSIC.

REFERENCES

Andreasen, M., & Nedergaard, S. (1996). Den-
dritic electrogenesis in rat hippocampal CA1
pyramidal neurons: functional aspects of Na+ and
Ca2+ currents in apical dendrites. Hippocampus ,
6, 79-95.

Canals, S., López-Aguado, L., & Herreras O.
(2005). Synaptically-recruited apical currents
are required to initiate axonal and apical spikes
in hippocampal pyramidal cells: modulation
by inhibition. Journal of Neurophysiology , 93,
909-918.

Colbert, C. M., & Johnston, D. (1998). Protein
kinase C activation decreases activity-dependent
attenuation of dendritic Na+ current in hip-
pocampal CA1 pyramidal neurons. Journal of
Neurophysiology 79, 491-495.

Gasparini, S., Migliore, M., & Magee, J.C. (2004).
On the initiation and propagation of dendritic
spikes in CA1 pyramidal neurons. Journal of
Neuroscience, 24, 11046-11056.

Golding, N. L. & Spruston, N. (1998). Dendritic
sodium spikes are variable triggers of axonal
action potentials in hippocampal CA1 pyramidal
neurons. Neuron , 21, 1189-1200.

Goldstein, S. S., & Rall W. (1974). Changes of
action potential shape and velocity for changing
core conductor geometry. Biophysical Journal,
14, 731-757.