Functional distribution of taste neurons in rat gustatory cortex —cross-correlation analysis

S204

16. Chemical Senses, Olfaction, and Taste

EFFECTS OF DOUBLE PULSE STIMULATION

411

PIRIFORM

MICHIO SUGITANI, Dept. of Physiology,

CORTEX

We previously

showed

IN GUINEA PIG

SLICES WITH A CUT IN LAYER Ia OR Ib REVEALED

TOKIO SUGAI, NORIHIKO Kanazawa

ON SIGNAL PROPAGATION

Medical University,

BY OPTICAL IMAGING

ONODA Uchinada,

that signal propagation

Ishikawa 920-0293, Japan

in the piriform

cortex (PC) elicited by stimulation

of layer In was

severely damaged when either layer Ia or Ib was cut. In the present study, double pulse stimulation

was applied to layer Ia of

slices where either layer Ia or Ib 0.4-0.7 mm caudal to the site of stimulation

if temporal summation

excitation

from the remaining

fiber system to pyramidal

was cut, to investigate

cells could recover the damaged

samples with layer Ia cut and in 68% of those with layer Ib cut, double pulse stimulation, obviously

increased

the excitability

in the region caudal to the cut. The excitability

signal propagation. as compared

induced

In 74% of

with single pulse,

by double pulse, however,

reached to at most 50% of that in the same region induced by single pulse before the cut was made. Thus, it is suggested convergence

of inputs from afferent and association

propagation

in PC.

YOKOTA,

Dept. of Physiology, We studied in gustatory

KUNIHIRO

and histologtcal were identified

patterns non-Pps.

Aicht-Gakum

cortex under anesthetized

taste profiles

were calculated

The taste profiles

EGUCHI AND TOYOHIKO

School of Dentistry,

corretograms coeffictents

cells is indispensable

FUNCTIONAL DISTRIBUTION OF TASTE NEURONS -CROSS-CORRELATION ANALYSIS.

412 TATSUKO

fibers onto pyramidal

locattons.

were similar wtth stgniftcant

were (+) in 38/17-O responses(32’3, The distance

Univ., Kusumoto,

rats the correlative

taste sttmulatton

to esttmate the similarity

Chtkusa-ku,

acttvttics

coefficients

of Pps). The percentages

of two dye marks in a pan w’as measured

strong signal

CORTEX

Nagoya 464-8650

of taste neuron patrs in relation to their

and sigmftcant

pcrtods(Postttve

peaks and/or

patrs;Pps).

troughs

Spearmans’s

in crosscorrelatton

pattern ol tiring of a neuron pair.

(+) tn 13130 patrs(43’1, of Pps) and the temporal ol (+) was sigruficantty

in 3 directions;

corttcal surface. Non-Pps were located more often along the rostra-caudal tn these two directions.

IN RAT GUSTATORY

of taste profiles and the temporal

correlation

for generating

that

SATOH

53 taste pairs were recorded,

in 30 pairs during

of

rostro-caudal

greater tn Pps than that of and perpendicular

asis ivhercas Pps were dtstrtbutcd

to the

rather evenly