• Nuclear Medicine and Molecular Imaging
• /
• v.42 no.1
• /
• pp.17-28
• /
• 2008

Purpose: It was well known that cerebral blood perfusion is normal or diffusely decreased in the majority of patients with Parkinson's disease (PD). Actually we interpreted brain perfusion SPECT images of PD patients in the clinical situation, we observed various cerebral perfusion patterns in patients with PD. So we performed brain perfusion SPECT to know the brain perfusion patterns of PD patients and the difference of perfusion patterns according to the sex and the age. Also we classified PD patients into small groups based on the brain perfusion pattern. Methods and Materials: Two hundred nineteen patients (M: 70, F: 149, mean age: $62.9{\pm}6.9$ y/o) who were diagnosed as PD without dementia clinically and 55 patients (M:15, F:40, mean age: $61.4{\pm}9.2$ y/o) as normal controls who had no past illness history were performed $^{99m}Tc$-HMP AO brain perfusion SPECT and neuropsychological test. Results: At first, we compared all patients with PD and normal controls. Brain perfusion in left inferior frontal gyrus, left insula, left transverse temporal gyrus, left inferior parietal lobule, left superior parietal lobule, right precuneus, right caudate tail were lower in patients with PD than normal controls. Secondly, we compared male and female patients with PD and normal controls, respectively. Brain perfusion SPECT showed more decreased cerebral perfusion in left hemisphere than right side in both male and female patients compared to normal controls. And there was larger hypoperfusion area in female patients compared with male. Thirdly, we classified patients with PD and normal controls into 4 groups according to the age and compared brain perfusion respectively. In patient below fifties, brain perfusion in both occipitoparietal and left temporal lobe were lower in PD group. As the patients with PD grew older, hypoperfusion area were shown in both frontal, temporal and limbic lobes. Fourthly, We were able to divide patients into small groups based on cerebral perfusion pattern. There was normal cerebral blood perfusion in 32 (14.7%) of 219 patients with PD, decreased perfusion on the frontal lobe in 45 patients (20.6%), the temporal lobe in 39 patients (17.4%), the parietal lobe in 39 patients (17.9%), the occipital lobe in 40 patients (18.3%), diffuse area in 14 patients (6.4%) and unclassified in 10 patients (4.6%). Fifthly, we compared the results of the neuropsychological test and cerebral perfusion pattern. There was no correlation between two tests except visuospatial function. Conclusion: Various perfusion state were found in patients with PD according to the age and sex. Also we were able to classify perfusion state into several groups and compare the neuropsychological test with cerebral perfusion.

• Korean Journal of Cognitive Science
• /
• v.27 no.2
• /
• pp.159-219
• /
• 2016

Mathematical ability is important for academic achievement and technological renovations in the STEM disciplines. This study concentrated on the relationship between neural basis of mathematical cognition and its mechanisms. These cognitive functions include domain specific abilities such as numerical skills and visuospatial abilities, as well as domain general abilities which include language, long term memory, and working memory capacity. Individuals can perform higher cognitive functions such as abstract thinking and reasoning based on these basic cognitive functions. The next topic covered in this study is about individual differences in mathematical abilities. Neural efficiency theory was incorporated in this study to view mathematical talent. According to the theory, a person with mathematical talent uses his or her brain more efficiently than the effortful endeavour of the average human being. Mathematically gifted students show different brain activities when compared to average students. Interhemispheric and intrahemispheric connectivities are enhanced in those students, particularly in the right brain along fronto-parietal longitudinal fasciculus. The third topic deals with growth and development in mathematical capacity. As individuals mature, practice mathematical skills, and gain knowledge, such changes are reflected in cortical activation, which include changes in the activation level, redistribution, and reorganization in the supporting cortex. Among these, reorganization can be related to neural plasticity. Neural plasticity was observed in professional mathematicians and children with mathematical learning disabilities. Last topic is about mathematical creativity viewed from Neural Darwinism. When the brain is faced with a novel problem, it needs to collect all of the necessary concepts(knowledge) from long term memory, make multitudes of connections, and test which ones have the highest probability in helping solve the unusual problem. Having followed the above brain modifying steps, once the brain finally finds the correct response to the novel problem, the final response comes as a form of inspiration. For a novice, the first step of acquisition of knowledge structure is the most important. However, as expertise increases, the latter two stages of making connections and selection become more important.

• Korean Journal of Psychosomatic Medicine
• /
• v.26 no.1
• /
• pp.59-67
• /
• 2018

Objectives : The aims of this study were to know the frequency and the nature of cognitive dysfunction in type 2 diabetics, and to reveal influencing variables on it. Methods : From eighty type 2 diabetics (42 males and 38 females), demographic and clinical data were obtained by structured interviews. Cognitive functions were measured using the MMSE-K (Korean Version of the Mini-Mental State Examination) and the Korean Version of the Montreal Cognitive Assessment (MoCA-K) tests. Severity of depression was evaluated by the Korean Version of the Hamilton Depression Rating Scale (K-HDRS). Results : 1) Among eighty type 2 diabetics, 13.75% were below 24 on the MMSE-K, while 38.8% were below 22 on the MoCA-K. 2) The total scores and subtest scores of the MoCA-K including visuospatial/ executive, attention, language, delayed recall and orientation were significantly lower in type 2 diabetics with cognitive dysfunction (N=31) than those without cognitive dysfunction (N=49) (p<0.001, respectively). 3) There were significant difference between type 2 diabetics with and those without cognitive dysfunction in age, education, economic status, body mass index, duration of diabetes, total scores of the K-HDRS, the MMSE-K and the MoCA-K (p<0.05, respectively). 4) The total scores of the MoCA-K had significant correlation with age, education, body mass index, family history of diabetes, duration of diabetes, total scores of the K-HDRS (p<0.05, respectively). 5) The risks of cognitive dysfunction in type 2 diabetics were significantly influenced by sex, education, fasting plasma glucose and depression. Conclusions : The cognitive dysfunction in type 2 diabetics seemed to be related to multiple factors. Therefore, more comprehensive biopsychosocial approaches needed for diagnosis and management of type 2 diabetes.

• Sleep Medicine and Psychophysiology
• /
• v.12 no.2
• /
• pp.122-132
• /
• 2005

Objectives: The objective of this study is to assess cognitive functions and their relationship with sleep symptoms in young narcoleptic patients. Methods: Eighteen young narcolepsy patients and 18 normal controls (age: 17-35 years old) were recruited. All narcolepsy patients had HLA $DQB_1$ *0602 allele and cataplexy. Several important areas of cognition were assessed by a battery of neuropsychological tests consisting of 13 tests: executive functions (e.g. cognitive set shifting, inhibition, and selective attention) through Wisconsin card sorting test, Trail Making A/B, Stroop test, Ruff test, Digit Symbol, Controlled Oral Word Association and Boston Naming Test; alertness and sustained attention through paced auditory serial addition test; verbal/nonverbal short-term memory and working memory through Digit Span and Spatial Span; visuospatial memory through Rey-Osterrieth complex figure test; verbal learning and memory through California verbal learning test; and fine motor activity through grooved pegboard test. Sleep symptoms in narcolepsy patients were assessed with Epworth sleepiness scale, Ullanlinna narcolepsy scale, multiple sleep latency test, and nocturnal polysomnography. Relationship between cognitive functions and sleep symptoms in narcolepsy patients was also explored. Results: Compared with normal controls, narcolepsy patients showed poor performance in paced auditory serial addition (2.0 s and 2.4 s), digit symbol tests, and spatial span (forward)(t=3.86, p<0.01; t=-2.47, p=0.02; t=-3.95, p<0.01; t=-2.22, p=0.03, respectively). There were no significant between-group differences in other neuropsychological tests. In addition, results of neuropsychological test in narcolepsy patients were not correlated with Epworth sleepiness scale score, Ullanlinna narcolepsy scale score and sleep variables in multiple sleep latency test or nocturnal polysomnography. Conclusion: The current findings suggest that young narcolepsy patients have impaired attention. In addition, impairment of attention in narcolepsy might not be solely due to sleep symptoms such as excessive daytime sleepiness.