Functional and morphological abnormalities of temporal lobe in patients with panic disorder
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Niigata University|
SHIOIRI Toshiki Niigata University, Graduate School of Medical and Dental Sciences, Associate Professor, 大学院・医歯学総合研究科, 助教授 (40235487)
HOSOKI Toshihiro Niigata University, Medical and Dental Hospital, Assistant, 医歯学総合病院, 助手 (00313544)
|Project Period (FY)
2001 – 2004
Completed(Fiscal Year 2004)
|Budget Amount *help
¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 2004 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 2003 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 2002 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 2001 : ¥900,000 (Direct Cost : ¥900,000)
|Keywords||blink rate / baroreflex / autonomic system / mental loading / pupillary light reflex / audiovisual stimulation / sympathetic nerve / panic disorder / IH-MRS / 不安障害|
1.Momentary changes in the cardiovascular autonomic system during mental loading in patients with panic disorder : a new physiological index "pmax"
Using a new physiological index "pmax"which could well reflect emotional reaction to visual stimuli (Yoshizawa et al.,2001), we studied momentary changes in the CAS in patients with panic disorder(PD) during audiovisual stimulation(AS) as mental loading. The pmax was an available index which could detect the momentary changes in the CAS during AS in both groups. The two-way ANOVA disclosed significant group and time effects on the pmax. The momentary response to emotional stimuli in the PD patients was slower than that in the normal control(NC) subjects. These findings suggest that there may be a dysfunction of the CAS in remitted PD patients and that the dysfunction may be one of the trait markers of PD.
2.Dysfunctional baroreflex regulation of sympathetic nerve activity in remitted patients with panic disorder : a new methodological approac
In this study, to assess the cardiovascular ANS function (baroreflex) in PD we used the power spectrum analysis as usual and the mean of lag time (τ) between the Mayer wave components, which was closely related to sympathetic nerve activity of vasomotor, of HR and BP variability as a new trial. We found that τ in the PD group was significantly shorter than that in the NC both before and after AS, especially before. These findings suggest that remitted PD patients may have a dysfunctional baroreflex regulation of sympathetic nerve activity.
3.Puppillary light reflex in panic disorder : a trial using audiovisual stimulation
In the present study, we determined whether PD patients exhibited abnormalities in the pupillary autonomic nervous system(ANS). Before and after AS, there were no significant differences in initial pupillary diameters in dark conditions (D1), pupillary diameters at maximum constriction (D2) and constriction ratios (CR : (D1-D2)/D1) between PD and NC subjects. However, the CR ratio (CR before/CR after) was significantly higher in the PD group than in the NC. These findings suggest that even remitted PD patients may have a dysfunctional PLR regulation with experimental stressors such as AS.
4.Abnormalities of GABA and glutamate concentration in patients with panic disorder
Using 3T MRI and -1H-MRS, we examined the concentrations of GABA and glutamate in frontal, temporal, and occipital lobes of patients with PD comparing with NC. We showed some abnormalities in left temporal lobe of PD group. The PD patients had a significant higher glutamate (p<0.03) and GABA (p<0.06) concentrations. These finding suggests that there is a change in the ratio of excitatory-inhibitory neurotransmitter levels in the left temporal lobe of PD subjects that may be related to alterted brain function. Less
Research Products (13results)