Biomedical subjects

I Hui Lee

Publications and source records attributed to I Hui Lee.

14 recordsLinked to original sources

PubMed2005

The correlation between striatal dopamine D2/D3 receptor availability and verbal intelligence quotient in healthy volunteers.

BACKGROUND: Although a correlation between the central dopaminergic system and intelligence may exist, the results from imaging studies remain inconclusive. The aim of this study was to explore the relationship between striatal dopamine D2/D3 receptor availability and verbal intelligence quotient (VIQ) using single photon emission computed tomography (SPECT). METHOD: Striatal D2/D3 receptor availability of 64 healthy subjects was determined with the [123I]iodobenzamide ([123I]IBZM) ligand. Intelligence quotients (IQs) of the subjects were measured by the Wechsler Adult Intelligence Scale--Revised (WAIS-R). RESULTS: In addition to age, left striatal D2/D3 receptor availability correlated positively with VIQ. In females, left striatal D2/D3 receptor availability was the only variable that correlated significantly with the similarities subtest of VIQ. CONCLUSIONS: There is a relationship between left striatal D2/D3 receptor availability and verbal intelligence, which varies, predominantly in males.

Adult↗

PubMed2005

Striatal dopamine D2/D3 receptor availability in male smokers.

It has been reported that the activation of the nicotine receptor evokes central endogenous dopamine release. However, whether smoking affects striatal dopamine D(2)/D(3) availability over the long run has not been well established in vivo. Fifteen male smokers and their matching controls were recruited. Striatal dopamine D(2)/D(3) receptor availability was assessed by single photon emission computed tomography with [(123)]IBZM Iodo-benzaimide. There was no significant difference in striatal D(2)/D(3) receptor availability between smokers and controls.

Adult↗

PubMed2005

The association between the Lie scale of the Maudsley personality inventory and striatal dopamine D2/D3 receptor availability of healthy Chinese community subjects.

The present study examined the relationship between the Lie scale scores and striatal D(2)/D(3) receptor availability with respect to the cerebellum in 42 healthy community volunteers in Taiwan using single photon emission computed tomography (SPECT) with [(123)I]iodo-benzoaminde (IBZM). Even after controlling of age and educational level, subjects' Lie scale scores of the Maudsley personality inventory correlate negatively with D(2)/D(3) receptor availability. Individual with higher Lie scale scores may have higher impulsivity due to lower dopaminergic availability.

Adult↗

PubMed2005

Correlation between striatal dopamine D2 receptor density and neuroticism in community volunteers.

The central dopaminergic system, as well as the central serotonergic system, has been reported to be correlated with higher neuroticism. The present study examined the relationship between striatal dopamine D(2) receptor density and neuroticism. Neuroticism was assessed with the Maudsley Personality Inventory, and psychiatric morbidity was evaluated with both the Mini International Neuropsychiatric Interview and the Hamilton Depression Rating Scale (HAM-D). Single photon emission computed tomography with [(123)I]iodo-benzamide was used to measure striatal dopamine D(2) receptor density. HAM-D scores and psychiatric morbidity in high-neuroticism individuals were higher than in low-neuroticism individuals. Moreover, striatal dopamine D(2) receptor densities were significantly correlated with the neuroticism score of the 41 subjects. The central dopaminergic system may play an important role in the neurobiological characteristics of neuroticism.

Adult↗

PubMed2005

Correlation between different memory systems and striatal dopamine D2/D3 receptor density: a single photon emission computed tomography study.

OBJECTIVE: Although studies have indicated that the human basal ganglia have a specific role in different memory systems, the functional significance of the striatal dopamine activities for the basal ganglia remains less clear. This study assessed the relationship between measures of striatal dopamine activities and indices of different memory systems in healthy individuals. METHOD: Single photon emission computed tomography and [123I]IBZM (iodobenzamide) were used to assess the striatal dopamine D2/D3 receptor density in 62 healthy volunteers aged between 19 and 61 years. All subjects underwent a Wechsler Memory Scale-Revised test. RESULTS: Dopamine D2/D3 receptor densities in the striatum decline with age. Stepwise regression analysis showed that verbal delayed recall and working memory account for most of the variance in dopamine D2/D3 measurements. These relationships remain significantly after controlling for age effects. CONCLUSIONS: Brain striatal dopamine activities are also significantly associated with various memory systems, in addition to motor functions. This may explain why patients with neuropsychiatric disorders may have both memory and motor impairments.

Adult↗

PubMed2005

Norms of performance of sustained attention among a community sample: Continuous Performance Test study.

The Continuous Performance Test (CPT) is a widely used measure of sustained attention, which is a preferred tool for assessing various mental functions. A well-established norm for CPT is essential when choosing a suitable threshold for classifying individuals as either case (CPT impairment) or non-case. The CPT performance of 900 adults who were randomly chosen from a community survey was measured to establish the norms for subgroups with different gender, age, and educational levels. The results revealed that age and educational level are significantly associated with the performance sensitivity (d') of CPT. Male subjects perform better than female subjects. Seventeen percent of the subjects scored higher on the masked CPT than on the unmasked CPT. Subjects who could not finish the masked CPT had the characteristics of older age and fewer years of education. When classifying a patient as case or non-case, his/her CPT performance should be considered relative to the norms for his/her gender, age, and educational levels.

Adult↗

PubMed2005

The relationship among insight, cognitive function of patients with schizophrenia and their relatives' perception.

Medically, insight is a multidimensional concept. Results of previous studies are inconclusive regarding the relationship between insight and global and cognitive functions. The aim of this study was to evaluate the relationship among insight, patients' global function, cognitive function of patients with schizophrenia and their key caregivers' perception about this disorder. Thirty-one patients with schizophrenia were recruited. Cognitive function such as memory index proved to be a significant predictor for patients' insight; environmental factors such as caregivers' perception was not. In addition to cognitive deficit, whether the other factors such as genetic variability, medication use, environmental factors, and illness severity, etc., could influence insight of patients will still be a controversial issue. Further multidimensional survey of the relationship with insight in a larger and comprehensive design is necessary.

Adult↗

PubMed2004

Association between cognitive performance and striatal dopamine binding is higher in timing and motor tasks in patients with schizophrenia.

The basal ganglia have received increasing attention with regard to their role in time pacing, motor function and other components of cognition. The aim of this study was to test whether the finer the motor activity and/or time perception performance were, the higher the striatal dopamine D(2) binding would be. Single photon emission computed tomography (SPECT) with [(123)I]iodobenzamide (IBZM) was performed to measure striatal D(2) receptor densities. A battery of neuropsychological tests, including the Wisconsin Card Sorting Test (WCST), the finger tapping test (FTT), and an attention test, was performed by patients with schizophrenia. Results indicated a strong correlation between the FTT score and striatal D(2) receptor binding. Neuroleptic dosage plays an important role in the relationship between cognitive tasks and striatal dopamine receptor densities. In addition, the striatal D(2) receptor density is more significantly correlated with attentional tests that consider the time effect than those that do not. Among the three tests performed, the WCST was least significantly correlated with striatal D(2) receptor densities. A decrease in striatal dopamine D(2) receptor density seems to be associated with impaired performance on optimal timing tasks and motor processing in patients with schizophrenia.

Adult↗

PubMed2004

Associated alterations of striatal dopamine D2/D3 receptor and transporter binding in drug-naive patients with schizophrenia: a dual-isotope SPECT study.

OBJECTIVE: In vivo imaging studies have revealed deregulated presynaptic or postsynaptic function of the midbrain dopaminergic system in patients with schizophrenia. To further delineate the neuropathological involvement of the presynaptic and postsynaptic dopamine neurons in schizophrenia, the authors examined brain D(2)-family receptor and dopamine transporter binding simultaneously in patients with drug-naive schizophrenia using the dual-isotope single photon emission computed tomography (SPECT) imaging technique. METHOD: Eleven patients with schizophrenia and 12 healthy comparison subjects were recruited. Striatal dopamine D(2)/D(3) receptor was measured with SPECT and [(123)I]iodobenzamide ([(123)I]IBZM), while dopamine transporter was measured with SPECT and [(99m)Tc]TRODAT-1. RESULTS: Striatal D(2)/D(3) receptor and dopamine transporter binding were unaltered in these drug-naive patients with schizophrenia. Nonetheless, D(2)/D(3) receptor binding measures were positively correlated with dopamine transporter binding measures in these patients but not in the comparison subjects. CONCLUSIONS: The associated presynaptic and postsynaptic disturbances of midbrain dopamine neurons could be clinically relevant in drug-naive patients with schizophrenia.

Adolescent↗

PubMed2004

Eye-hand preference in schizophrenia: sex differences and significance for hand function.

Hand preference and eye dominance were investigated in 73 (30 women, 43 men) schizophrenic patients and 71 (30 women, 41 men) healthy controls. There were significantly more schizophrenic patients and normal controls who were significantly right-hand dominant. However, schizophrenic patients showed a significant excess of left-eye dominance relative to controls (65.8% vs 29.6%; Odds Ratio= 4.75, p< .001). In addition, female schizophrenic patients showed a higher rate of nonright (either left or inconsistent) eye dominance (80%) than male schizophrenic patients (55.8%) and controls (33.3%). Analysis of hand performance on the Purdue Pegboard Test indicated that schizophrenic patients who showed crossed eye-hand dominance scored higher than did patients without crossed eye-hand dominance.

Adult↗

PubMed2003

Correlation between fine motor activity and striatal dopamine D2 receptor density in patients with schizophrenia and healthy controls.

Striatal dopamine D2 receptor density is an important indicator of many neuropsychiatric disorders and also of motor activity. This study examined the relationship between a fine motor task (finger tapping test, FTT) and striatal D2 dopamine receptor density by examining 20 healthy volunteers and 20 schizophrenic patients. Striatal D2 receptor density was determined with single photon emission computed tomography using [123I]IBZM (iodo-benzamide). The correlation between the FTT score and striatal D2 receptor density was statistically significant not only in the patient group but also in healthy controls. The FTT scores and striatal D2 receptor density were lower in medicated patients than that in healthy controls. Compared with the Simpson-Angus Scale scores, the FTT scores were more strongly associated with striatal D2 receptor density. The use of neuroleptic medication seemed to influence the associations between FTT scores and striatal D2 receptor density in the patient group. The FTT scores and striatal D2 receptor density were age-sensitive in healthy controls. FTT may be a more sensitive tool for detecting neuroleptic-induced motor impairment in patients with schizophrenia. The sensitivity of the FTT to age and neuroleptic effects may be explained in part by a decline in dopamine D2 density.

Adolescent↗

PubMed2003

Association between regional cerebral blood flow and eye-tracking performance and the Wisconsin Card Sorting Test in schizophrenics: a single photon emission computed tomography study.

The objectives of this study were (1). to examine the changes in regional cerebral blood flow (rCBF) during Wisconsin Card Sorting Test (WCST) performance in two different eye-tracking groups; (2). to explore the relationship between eye-tracking movement and rCBF at rest; and (3). to estimate the association between WCST performance and rCBF in patients with schizophrenia. A total of 17 patients with schizophrenia were recruited. SPECT with Tc-99m HMPAO (Tc-99m hexamethylpropyleneamine oxime) was carried out while patients were performing the WCST and resting. Brodmann area 9 of the prefrontal cortex, a part of the dorsal lateral prefrontal cortex (DLPFC), was less activated during performance of the WCST in poor trackers (relative to good trackers). The eye pursuit tracking error measure in schizophrenic patients was negatively associated with decreases in rCBF in the middle temporal area, superior parietal lobule, thalami, and caudate nuclei. The rCBF increased significantly in the superior temporal gyri, inferior parietal lobe, and some frontal regions during WCST performance; however, this was not the case in the DLPFC. Additionally, significant correlations were found between WCST scores and rCBF during WCST performance in the prefrontal lobes, and in thalamic and cerebellar regions. Our findings suggest that the rCBF changes during WCST performance may be distinctive in different eye-tracking groups. Our results confirm the hypothesis that the middle temporal area, superior parietal lobule, thalami, and caudate nuclei-mainly parts of the oculomotor circuit-are involved in eye pursuit tracking. Surprisingly, no significant association was found in the frontal eye field. Although the frontal lobe plays a significant role in WCST performance, our findings demonstrate that WCST performance is widely involved with other regions in patients with schizophrenia.

Adult↗

PubMed2003

Olanzapine in Chinese treatment-resistant patients with schizophrenia: an open-label, prospective trial.

The role of olanzapine in treatment-resistant schizophrenia has still not been clearly resolved. In addressing this issue, the current report presents an open-label, prospective, 13 week trial with olanzapine use in Chinese schizophrenic patients who were resistant to more than two different classes of antipsychotics during a minimal 4 week treatment period for each antipsychotic drug at adequate dosage. Fifty-one inpatients were recruited after a cross-titration period and given 10-25 mg of olanzapine daily, without any concomitant antipsychotic medication. Patients were evaluated with the Brief Psychotic Rating Scale (BPRS), the Positive and Negative Symptoms Scale, the Clinical Global Impression Scale (CGI), the Abnormal Involuntary Movement Scale, the Simpson-Angus scale, and the Barnes Akathisia Scale. The olanzapine-treated patients showed significant improvement in both the positive and negative symptoms of schizophrenia by the end of the study. Overall, 20 of 51 (39.2%) responded to 10-25 mg of olanzapine per day as measured by the BPRS and CGI scores. Five patients dropped out due to the worsening of their psychotic symptoms, two patients discontinued owing to poor drug compliance, and the remaining patient complained of a lack of efficacy. Extrapyramidal side-effects were mild, and anticholinergic medications required has decreased. The present open study suggests that olanzapine may be effective and well-tolerated in Chinese treatment-resistant schizophrenic patients. Further double-blinded trials are needed to confirm this result.

Adult↗

PubMedDate not supplied

Psychiatric morbidity and posttraumatic symptoms among earthquake victims in primary care clinics.

Three months after the devastating Chi-Chi earthquake (magnitude of 7.3 on the Richter scale) struck the central area of Taiwan, 663 victims were screened for psychiatric morbidity at a local general hospital in a community mental health program. The rate of psychiatric morbidity as defined by the 12-item Chinese Health Questionnaire as greater than 4, was 24.5%. Posttraumatic symptoms were still prevalent. The rate of posttraumatic stress disorder was 11.3%, and the rate of partial PTSD was 32.0%. Variables associated with the presence of psychiatric morbidity and posttraumatic symptoms included female gender, old age, financial loss, obsessive trait, and nervous trait. A disproportionate use of mental health services (18%) was found, suggesting an urgent need to deliver mental health care to disaster victims at local medical settings. In addition, health care professionals who work with the earthquake victims need to be promptly and efficiently trained in mental health crisis intervention.

Adult↗