Browsing by Author "Lin, Ching-Hung"

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Anatomic Differences between Parkinson\'s Disease and Essential Tremor Using ICA-based Brain Morphometry
(2013)
Duann, Jeng-Ren
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Lin, Ching-Hung
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Chen, Chun-Min
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Lu, Ming-Kuei
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Tsai, Chon-Haw
This study used independent component analysis (ICA) to decompose the surrogate image data by concatenating in space multiple subjects\' anatomical images after spatial normalization and smoothing to make all images in the same space. The multiple-subject anatomical image data included three different subject/patient populations, namely the Parkinson\'s disease (PD) and essential tremor (ET) as well as age-matched normal control (NC) subjects. In so doing, we were to extract the independent components showing significant group differences caused by the morphometric changes due to the neurological diseases. Such an independent component-based morphometry (ICBM) applied to both the grouped gray-matter and white-matter image data could be used to successfully reveal the brain areas within the gray and white matters showing significant group differences. In gray matter, we found a majority of basal ganglia brain areas associated with NC > PD, which well represented the causes of PD reported in the literature. In addition, the ICBM also found the brain areas of right superior temporal gyrus, right angular gyrus (BA 39), right inferior temporal gyrus, and left middle temporal gyrus (BA 37) associated with NC > ET. On the other hand, a more complicated patterns were found in the white matter associated with PD > ET and ET > PD conditions.
Are Normal Decision-Makers Sensitive to Changes in Value Contrast under Uncertainty? Evidence from the Iowa Gambling Task
(2014-07-18)
Lee, We-Kang
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Su, Yi-An
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Song, Tzu-Jiun
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Chiu, Yao-Chu
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Lin, Ching-Hung
The Iowa Gambling Task (IGT) developed by Bechara et al. in 1994 is used to diagnose patients with Ventromedial Medial Prefrontal Cortex (VMPFC) lesions, and it has become a landmark in research on decision making. According to Bechara et al., the manipulation of progressive increments of monetary value can normalize the performance of patients with VMPFC lesions; thus, they developed a computerized version of the IGT. However, the empirical results showed that patients\' performances did not improve as a result of this manipulation, which suggested that patients with VMPFC lesions performed myopically for future consequences. Using the original version of the IGT, some IGT studies have demonstrated that increments of monetary value significantly influence the performance of normal subjects in the IGT. However, other research has resulted in inconsistent findings. In this study, we used the computerized IGT (1X-IGT) and manipulated the value contrast of progressive increments (i.e., by designing the 10X-IGT, which contained 10 times of progressive increment) to investigate the influence of value contrast on the performance of normal subjects. The resulting empirical observations indicated that the value contrast (1X-vs. 10X-IGT) of the progressive increment had no effect on the performance of normal subjects. This study also provides a discussion of the issue of value in IGT-related studies. Moreover, we found the "prominent deck B phenomenon" in both versions of the IGT, which indicated that the normal subjects were guided mostly by the gain-loss frequency, rather than by the monetary value contrast. In sum, the behavioral performance of normal subjects demonstrated a low correlation with changes in monetary value, even in the 10X-IGT.
Mirrored Prominent Deck B Phenomenon: Frequent Small Losses Override Infrequent Large Gains in the Inverted Iowa Gambling Task
(2012-10-16)
Lin, Ching-Hung
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Song, Tzu-Jiun
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Lin, Yu-Kai
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Chiu, Yao-Chu
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應用化學系
Since Bechara et al. pioneered its development, the Iowa Gambling Task (IGT) has been widely applied to elucidate decision behavior and medial prefrontal function. Although most decision makers can hunch the final benefits of IGT, ventromedial prefrontal lesions generate a myopic choice pattern. Additionally, the Iowa group developed a revised IGT (inverted IGT, iIGT) to confirm the IGT validity. Each iIGT trial was generated from the trial of IGT by multiplying by a "2" to create an inverted monetary value. Thus, bad decks A and B in the IGT become good decks iA and iB in the iIGT; additionally, good decks C and D in the IGT become bad decks iC and iD in the iIGT. Furthermore, IGT possessed mostly the gain trials, and iIGT possessed mainly the loss trials. Therefore, IGT is a frequent-gain-based task, and iIGT is a frequent-loss-based task. However, a growing number of IGT-related studies have identified confounding factors in IGT (i.e., gain-loss frequency), which are demonstrated by the prominent deck B phenomenon (PDB phenomenon). Nevertheless, the mirrored PDB phenomenon and guiding power of gain-loss frequency in iIGT have seldom been reexamined. This experimental finding supports the prediction based on gain-loss frequency. This study identifies the mirrored PDB phenomenon. Frequent small losses override occasional large gains in deck iB of the iIGT. Learning curve analysis generally supports the phenomenon based on gain-loss frequency rather than final outcome. In terms of iIGT and simple versions of iIGT, results of this study demonstrate that high-frequency loss, rather than a satisfactory final outcome, dominates the preference of normal decision makers under uncertainty. Furthermore, normal subjects prefer "no immediate punishment" rather than "final reward" under uncertainty.
Reexamining the validity and reliability of the clinical version of the Iowa gambling task: evidence from a normal subject group
(2013-05-29)
Lin, Ching-Hung
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Song, Tzu-Jiun
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Chen, Ying-Ying
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Lee, We-Kang
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Chiu, Yao-Chu
Over past decade, the Iowa gambling task (IGT) has been utilized to test various decision deficits induced by neurological damage or psychiatric disorders. The IGT has recently been standardized for identifying 13 different neuropsychological disorders. Neuropsychological patients choose bad decks frequently, and normal subjects prefer good expected value (EV) decks. However, the IGT has several validity and reliability problems. Some research groups have pointed out that the validity of IGT is influenced by the personality and emotional state of subjects. Additionally, several other studies have proposed that the "prominent deck B phenomenon" (PDB phenomenon) - that is, normal subjects preferring bad deck B - may be the most serious problem confronting IGT validity. Specifically, deck B offers a high frequency of gains but negative EV. In the standard IGT administration, choice behavior can be understood with reference to gain-loss frequency (GLF) rather than inferred future consequences (EV the basic assumption of IGT). Furthermore, using two different criteria (basic assumption vs. professional norm) results in significantly different classification results. Therefore, we recruited 72 normal subjects to test the validity and reliability of IGT. Each subject performed three runs of the computer-based clinical IGT version. The PDB phenomenon has been observed to a significant degree in the first and second stages of the clinical IGT version. Obviously, validity, reliability, and the practice effect were unstable between two given stages. The present form of the clinical IGT version has only one stage, so its use should be reconsidered for examining normal decision makers; results from patient groups must also be interpreted with great care. GLF could be the main factor to be considered in establishing the constructional validity and reliability of the clinical IGT version.
The clonic phase of seizures in patients treated with electroconvulsive therapy is related to age and stimulus intensity
(2013-12-23)
Wang, Chao-Chih
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Lin, Ching-Hung
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Chiu, Yao-Chu
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Tseng, Chih-Chieh
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生醫電子轉譯研究中心
Background: Electroconvulsive therapy (ECT) is effective in the treatment of major depressive disorder and schizophrenia in patients who are drug-naive or less-receptive to antipsychotic drugs. Several studies have discussed the correlation between patient characteristics, input-current volume, and seizure duration. According to the present principle of ECT guidelines, the therapeutic effect of ECT mostly correlates with seizure duration. As the tonic phase is different from the clonic phase with respect to brain function and activity, it is informative to analyze both the tonic and clonic phases. Thus, this study sought to clarify the relationship between the features of the two phases, and to re-examine and refine guidelines regarding ECT treatment. Method: ECT-course data from 44 schizophrenia or bipolar I patients were recollected, including the number of treatments that they had received, their gender, age, and the association of these characteristics with motor seizure duration was analyzed. A two-factor correlation was employed to test the relationship between each of the two factors. Result: The post-analysis results indicate that seizure duration and age are significantly correlated. Older patients had relatively short seizure durations after ECT-treatment. Notably, a negative correlation was only found between age and the clonic phase of the seizure, not between age and the tonic phase. Furthermore, this study also found an inverse relationship between ECT-intensity and the clonic phase, but not between ECT-intensity and the tonic phase. Conclusion: This study demonstrated that age and ECT-intensity are negatively correlated with seizure duration, particularly in the clonic phase. The present observations are not fully consistent with the basic guidelines of the APA-ECT practical manual. Accordingly, the predictions regarding the therapeutic effect of ECT can be based on both the seizure duration and the clonic phase.
VBM reveals brain volume differences between Parkinson's disease and essential tremor patients
(2013-06-14)
Lin, Ching-Hung
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Chen, Chun-Ming
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Lu, Ming-Kuei
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Tsai, Chon-Haw
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Chiou, Jin-Chern
Symptoms of essential tremor (ET) are similar to those of Parkinsons disease (PD) during their initial stages. Presently, there are few stable biomarkers available on a neuroanatomical level for distinguishing between these two diseases. However, few investigations have directly compared the changes in brain volume and assessed the compensatory effects of a change in the parts of the brain associated with PD and with ET. To determine the compensatory and/or degenerative anatomical changes in the brains of PD and ET patients, the present study tested, via two voxel-based morphometry (VBM) approaches (Basic vs. DARTEL VBM processing), the anatomical brain images of 10 PD and 10 ET patients, as well as of 13 age-matched normal controls, obtained through a 3T magnetic resonance scanner. These findings indicate that PD and ET caused specific patterns of brain volume alterations in the brains examined. In addition, our observations also revealed compensatory effects, or self-reorganization, occurring in the thalamus and the middle temporal gyrus in the PD and ET patients, due perhaps in part to the enhanced thalamocortical sensorimotor interaction and the head-eye position readjustment, respectively, in these PD and ET patients. Such a distinction may lend itself to use as a biomarker for differentiating between these two diseases.