Object Type:
receptor2
Description:
Olfactory Receptor. Takes weighted sum of any number of
messages to get the activation for a channel. The messages
represent components of an olfactory stimulus.
Author:
U. S. Bhalla, Caltech (1/90)
----------------------------------------------------------------------------ELEMENT PARAMETERS
DataStructure:
olf_receptor2_type
[in src/olf/olf_struct.h]
Size:
172 bytes
Fields:
response
table of weights to be set for each odor
nodors
number of odors
tau1
open time constant of channel
tau2
close time constant of channel
gmax
peak conductance
Ik
channel current
modulation scale all odors; gain control on responses
Gk
resulting channel conductance
Ek
equilibrium potential
activation
channel activation calculated from
incoming
messages
allocated
X
Y
xconst1
xconst2
yconst1
yconst2
norm
internal flag
state variable for time response
state variable for time response
internal variable, not normally set by
internal variable, not normally set by
internal variable, not normally set by
internal variable, not normally set by
internal variable, not normally set by user
user
user
user
user
----------------------------------------------------------------------------SIMULATION PARAMETERS
Function:
OlfReceptor2
Classes:
segment
channel
Actions:
INIT
PROCESS
RESET
RECALC
[in src/olf/receptor2.c]
SET
CHECK
SAVE2
RESTORE2
Messages:
VOLTAGE Vm
usual message from parent compartment
to channel to tell what the membrane
potential is
ODOR activation odor_no describes odor; activation = strength
of particular odor; odor_no = integer
specifying response table index
having
weight for that odor
MODULATION modulation sets modulation field; provides means
for scaling the overall sensitivity of
receptor up or down
----------------------------------------------------------------------------Notes:
Does a weighted sum of odors to get activation
of a channel with usual conductance properties.
The receptor2 element is a much more realistic version of an
olfactory receptor protein-membrane channel complex than
the
receptor element. The receptor2 is a channel similar to
the
synchan element, except that this channel responds to
odors
via ODOR messages, and does not have synapses with
weights and
delays.
Any number of odor messages may be sent to the receptor2.
They are scaled by the weights in the response table, and
then
their summed effects act as the activation of the
channel. The
channel has the usual time courses and conductance
fields, and
can be incorporated into membrane compartments just like
ordinary synaptic channels.
Example:
Scripts/neurokit/prototypes/newbulbchan.g
See also:
receptor