Functional mapping of visual cortical areas by combined application of grating and random-dot stimuli with 3D magnetometer-spatial filter array system and functional MRI

S269 FUNCTIONAL MAPPING OF VISUAL CORTICAL AREAS BY COnlBlNED APPLICATIOS OF GRATING AND RANDOM-DOT STIMULI WITH 3D MA<;NETOILIETER-SPc\T14L FILTER AR-

593

RAY SYSTEM AND FUNCTIONAL MRI. KEh-JI YOSHIKAWA’. KEISI_lKE TOYAMA’. YOSHIAKI TAKANASHI’. YOSHIO OHTANl:. HIROLORI YAMAMOTO-. YOSHIb4ICHI EJIMA’. SHOUICHI OKAMURA’. MASAYOSHI FUKL’NAGA’. CHUZOI’ TANAKA’. TOSHIHIKO I:lIlSL1 OX41 ‘K ‘ori) Inst Tcc11 I tic‘ Kyoto Prd. Univ. Mcd~cine. K;imig> o-ku. Kyrltr) 60_‘Dept. Ph,ysioI. and ‘Dept. Neurolof Eng~nccr~n~~ and Design, Sakvo-ku. k veto 605-X5X5. IDi\,. C,WJIII\C NCLII~WI.. Kvc,tci I‘~I\,.. S~,~I. (12‘)~(1300 ‘Shlmad/u t;o.. Nakagyo-ku. ~yoto 6031X5 I 1. “Dept. NWWI-g.. bl/lcq~ a Ncul.al respr~nscs prdLlccd Ln the left occipit;ll cortex by prcacnt;lti 9X’/: 1. Accord~nfly. the sp:~ti;d I‘ilters rcvcalcd single-peaked rcsponscs distrihutcd in ;I cortical reg1011 ;NOLIII~ the calc~u~~~~e\LIICLIS probably corrcspondi y 10 V I SRD\ and MRDs produced muI&pc&ed ME&. for which the ~Llr~mt-s~L~r~c anulyais less rcliahly loc;lli/ed the CLII~~CII~-S~~LII’C‘C (poodles 01 t‘it < 95 ‘Z ). The spatial filters dcmonstratcd that responses to SRDs distii hurcd III ;Lwider- COIIIUI ;II’C;I includm, I’\; I. all ill’c’;l \LIITilllllcllIlf a~-ca mcluding V I aml L’21.7 AS VI corresponding to V2/3 than that l’or SSGs. while those to MRDs dlstrihuted III ;I CVCII hrcdcrcort~cal well as the one antero-inferior to V2/3. The results wcrc Illrthel-confirmed hy mapping the cortical xcxs x~~v;Lted by the th1.w I\ ps of visual stimuli using the functional MRI. In summary. SSGs sclcctivcly activated VI. SRDs ;tctivatcd V I and VY3. ;IIKI MRD\ ;,I; 01 VI V213 and VS. Thcsc findings open ;I way for functional mapplnf ol‘visrial colllcal ;Irus using lhc l!ircc lypcs 01 \.ixuiil stimnll.

594

CHANGE

OF CORTICAL ACTIVITIES

KENTARO

INOUE, RYUTA KAWASHIMA.

Dept. of Nuclear Medicine and Radiology,

DURING VISUOMOTOR

KAZUNORI

LEARNING-A

PET STUDY

SATO, HIROSHI FUKUDA

IDAC, Tohoku Univ.. Sendai. Miyagi 980-8575

In order to find out which areas would be activated in relation to the sensorimotor

learning and to examine whether there

U’;LS a

change in activity among those areas activated between the early and the late stage of learning, we measured regional ccrchral blood flow (rCBF) in six subjects to study changes of cerebral activities during learning of visually guided pointings discrepancy cortices

of visuomotor

showed

coordination.

significant

increases

During the early stage of learning,

in rCBF.

significant increase of rCBF, however,

anterior parietal cortex of the right hemisphere

phase of retaining acquired sensorimotor

A FUNCTIONAL

595 KAZUHIKO

Hi-receptor

observed

(HlR) antagonists

impaired

cognitive

activation

regional

performance

MASATOSHI

INDUCED

coordinates

in

to the late

BY SEDATIVE ANTIHISTAMINE.

ITOH AND TAKEHIKO

Tohoku University

School of Medicine

in the world. Although

doses, the neural correlates

WATANABE’.

and ‘Cyclotron and Radioisotope

in frontal cortex. To investigate

with the decreased

sleepiness.

HlR,

properties

in human volunteers.

activity

are not well understood.

task using H,‘50-PET. in anterior

often We

The regional blockade of H 1R was

d-chlorpheniramine

the brain state associated

brain activity during attention-demanding is associated

it is well known that antihistamines

of these sedative

and anterior cingulate cortex, and intravenous

activity in right prefrontal

and arousal through

antihistamine-induced

0KAMURA2.3,

OF SLEEPINESS

regional blocking effect of antihistamine

(2 mg) blocked over 60 % of HlR

midbrain and the enhanced

visuomotor

coordination.

are widely used medications

mainly in frontal, temporal

sedation we measured

also showed

Sendai 980-8575, Japan

have sedative effects in recommended have used PET to visualize

parietal cortices

became active during the late stage. These results indicate dynamic changes

I and 2Geriatric Medicine,

Center, Tohoku University,

with a

parietal and prefrontal

in the prefrontal cortex. On the other hand. the

learning from the early phase of remapping

NEUROANATOMY

YANAI’, NOBUYUKI

Depts. of ‘Pharmacology

During the late stage, the bilateral posterior

increases in rCBF were not obserbed

cortical areas in the course of sensorimotor

the bilateral posterior

cingulate

at a therapeutic

dose

with antihistamine-induced The results showed that the gyms, temporal

cortex and

and inferior parietal cortex. Given the role of brain histamine in cortical

the pattern of modulated

activity in these cortical areas provides a biological

basis for