Attention deficit hyperactivity disorder（ADHD） is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have ex...Attention deficit hyperactivity disorder（ADHD） is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients.展开更多
Attention deficit and hyperactivity disorder（ADHD） is a disorder characterized by behavioral symptoms including hyperactivity/impulsivity among children,adolescents,and adults.These ADHD related symptoms are influen...Attention deficit and hyperactivity disorder（ADHD） is a disorder characterized by behavioral symptoms including hyperactivity/impulsivity among children,adolescents,and adults.These ADHD related symptoms are influenced by the complex interaction of brain networks which were under explored.We explored age-related brain network differences between ADHD patients and typically developing（TD） subjects using resting state f MRI（rs-f MRI） for three age groups of children,adolescents,and adults.We collected rs-f MRI data from 184 individuals（27 ADHD children and 31 TD children;32 ADHD adolescents and 32 TD adolescents;and 31 ADHD adults and 31 TD adults）.The Brainnetome Atlas was used to define nodes in the network analysis.We compared three age groups of ADHD and TD subjects to identify the distinct regions that could explain age-related brain network differences based on degree centrality,a well-known measure of nodal centrality.The left middle temporal gyrus showed significant interaction effects between disease status（i.e.,ADHD or TD） and age（i.e.,child,adolescent,or adult）（P 0.001）.Additional regions were identified at a relaxed threshold（P 0.05）.Many of the identified regions（the left inferior frontal gyrus,the left middle temporal gyrus,and the left insular gyrus） were related to cognitive function.The results of our study suggest that aberrant development in cognitive brain regions might be associated with age-related brain network changes in ADHD patients.These findings contribute to better understand how brain function influences the symptoms of ADHD.展开更多
OBJETTIVE: To observe the effects of Yinxingdamo Injection combined with oxiracetam capsule on cognitive function and neurological deficit in patients with acute cerebral infarction. METHODS: A total of 76 patients wi...OBJETTIVE: To observe the effects of Yinxingdamo Injection combined with oxiracetam capsule on cognitive function and neurological deficit in patients with acute cerebral infarction. METHODS: A total of 76 patients with acute cerebral infarction were randomly divided into observation group and control group, with 38 patients in each group. Patients in the control group were treated with conventional western medicine and oxiracetam capsules while patients in the observation group were given Yinxingdamo injection intravenous drip treatment on the basis of the same treatment. After 4 weeks of treatment, the cognitive function of the two groups before and after treatment was observed [Simple Intelligence Scale(MMSE Score), Montreal Cognitive Assessment Scale(MoCA Score)], Neurological Deficit [Chinese Stroke Scale(CSS Score), Daily Life Activity ability(ADL score)], free radical biochemical indicators [malondialdehyde(MDA), oxide dismutase(SOD)] changes, and statistical effects of two groups. RESULTS: After treatment, the total effective rate of the observation group was 92.1%, which was significantly higher than 73.7% of the control group(P < 0.05). The MMSE score and MoCA score of the two groups were significantly increased after treatment(P < 0.05), and the MMSE score and MoCA score inobservation group were significantly increased after treatment than the control group(P < 0.05). The CSS scores of the two groups were significantly decreased after treatment(P < 0.05), and the ADL scores were significantly increased(P < 0.05). The improvement of CSS score and ADL score in the observation group were significantly better than those in the control group(P < 0.05), and serum MDA levels were significantly decreased in both groups after treatment(P < 0.05), and SOD levels were significantly increased(P < 0.05), and the improvement of MDA and SOD levels in the observation group was significantly better than that in the control group group(P < 0.05). CONCLUSION: Yinxingdamo injection combined with oxiracetam capsule can effectively inhibit the oxygen free radical reaction injury in patients with acute cerebral infarction, and significantly improve the symptoms of cognitive dysfunction and neurological deficit in patients. Its curative effect is exact and worthy of clinical application.展开更多
Aims: This study was designed to verify the proportion of Japanese adults with pervasive developmental disorder (PDD) who met the diagnostic criteria (other than E) for attention-deficit/hyperactivity disorder (ADHD) ...Aims: This study was designed to verify the proportion of Japanese adults with pervasive developmental disorder (PDD) who met the diagnostic criteria (other than E) for attention-deficit/hyperactivity disorder (ADHD) in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR). Furthermore, we examined to what extent adults with PDD think that they exhibit ADHD symptoms. Methods: We developed an original Japanese self-report questionnaire to determine the presence or absence of 18 symptoms from the diagnostic criteria for ADHD in the DSM-IV-TR. We administered the questionnaire to 64 adults with high-functioning PDD (45 men and 19 women) and 21 adults with ADHD (10 men and 11 women), aged 18 to 59 years, with a full-scale intelligence quotient ≥75. Target patients were evaluated for ADHD by their psychiatrists. Results: Twenty-nine (45.3%) adults with PDD also had ADHD. The percentage of these adults who had over six perceived inattention symptoms from the DSM-IV-TR was 96.6%. The percentage of these adults who had over six perceived hyperactivity-impulsivity symptoms was 65.5%. Thirty-five (55.6%) adults with PDD responded that they were aware of having ADHD symptoms at the level of the relevant diagnostic criteria. Conclusions: The present study is the first to examine the frequency of objective and perceived ADHD symptoms in adults with PDD in Japan. Our results show that both objective and perceived ADHD symptoms frequently appear in a large number of adults with PDD. This suggests that it is necessary to attend to concomitant ADHD symptoms in the medical care of adults with PDD.展开更多
Background: Magnocellular deficit theory is among the different hypotheses that have been proposed to explain the pathophysiology of developmental dyslexia (DD). Dysfunction of the magnocellular system in DD has been ...Background: Magnocellular deficit theory is among the different hypotheses that have been proposed to explain the pathophysiology of developmental dyslexia (DD). Dysfunction of the magnocellular system in DD has been investigated using mainly visual evoked potentials (VEPs), particularly transient VEPs, although recently abnormal steady-state VEPs have also been reported. The brain regions responsible for the abnormal VEPs in DD have yet to be elucidated, however. In this study, we performed functional magnetic resonance imaging and electroencephalography (fMRI-EEG) simultaneously to elucidate the brain areas that were found in a previous study to be activated through stimulation of the magnocellular system, and then investigated the mechanism involved in the dysfunction seen in DD.Methods: Subjects were 20 healthy individuals (TYP group;13 men, 7 women;mean ± standard deviation age, 26.3 ± 5.53 years) and 2 men with DD (aged 42 and 30 years). Images of brain activity were acquired with 3-Tesla MRI while the viewing the reversal of low-spatial frequency and low-contrast black-and-white sinusoidal gratings. EEG was recorded concurrently to obtain steady-state VEPs.Results: Stimulus frequency-dependent VEPs were observed in the posterior region of the brain in the TYP group;however, VEP amplitudes in both DD patients were clearly smaller than those in TYP. fMRI images revealed that both the primary and secondary visual cortices were activated by black-and- white sinusoidal gratings in the TYP group, whereas activity in the visual cortex overall was reduced in both DD patients.Conclusions: Present low spatial and high reversal frequency visual stimuli activated the primary visual cortex presumably through predominant activation of the magnocellular pathway. This finding indicates that some cases of adult patients of DD involve impairment of the visual magnocellular system.展开更多
Attention deficit and hyperactivity disorder （ADHD）, a prevalent syndrome in children worldwide, is characterized by impulsivity, inappropriate inattention, and/or hyperactivity. It seriously afflicts cognitive deve...Attention deficit and hyperactivity disorder （ADHD）, a prevalent syndrome in children worldwide, is characterized by impulsivity, inappropriate inattention, and/or hyperactivity. It seriously afflicts cognitive development in childhood, and may lead to chronic under-achievement, academic failure, problematic peer relationships, and low self-esteem. There are at least three challenges for the treatment of ADHD. First, the neurobiological bases of its symptoms are still not clear. Second, the commonly prescribed medications, most showing short-term therapeutic efficacy but with a high risk of serious side-effects, are mainly based on a dopamine mechanism. Third, more novel and efficient animal models, especially in nonhuman primates, are required to accelerate the development of new medications. In this article, we review research progress in the related fields, focusing on our previous studies showing that blockade of prefrontal cortical a2A-adrenoceptors in monkeys produces almost all the typical behavioral symptoms of ADHD.展开更多
The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（A...The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（ADHD）, but it has been difficult to identify the mechanisms for regulating emotional problems from the understanding of ADHD comorbidity with disruptive behavior disorders（DBD）. Research based on ＂cool＇＇ and ＂hot＇＇executive functional theory and the dual pathway models,which are thought of as applied response inhibition and delay aversion, respectively, within the neuropsychological view of ADHD, has shed light on emotional responding before and after decontextualized stimuli, while CSTC circuit-related domains have been suggested to explain the different emotional symptoms of ADHD with or without comorbid DBD. This review discusses the role of abnormal connections in each CSTC circuit, especially in the emotion circuit, which may be responsible for targeted executive dysfunction at the neuroscience level. Thus, the two major domains – abstract thinking（cool） and emotional trait（hot） – trigger the mechanism of onset of ADHD.展开更多
In this article, the expected discounted penalty function Фδ,α （u） with constant interest δ and ＂discounted factor＂ exp（-αTδ） is considered. As a result, the integral equation of Фδ,α （u） is derived a...In this article, the expected discounted penalty function Фδ,α （u） with constant interest δ and ＂discounted factor＂ exp（-αTδ） is considered. As a result, the integral equation of Фδ,α （u） is derived and an exact solution for Фδ,α （0） is found. The relation between the joint density of the surplus immediately prior to ruin, and the deficit at ruin and the density of the surplus immediately prior to ruin is then obtained based on analytical methods.展开更多
Prefrontal dysfunction in patients with attention-deficit/hyperactivity disorder (AD/HD) has been repeatedly detected on a behavioral level, and various brain-imaging studies have elucidated the pathophysiology of AD/...Prefrontal dysfunction in patients with attention-deficit/hyperactivity disorder (AD/HD) has been repeatedly detected on a behavioral level, and various brain-imaging studies have elucidated the pathophysiology of AD/HD. Recent advances in near-infrared spectroscopy (NIRS) have enabled noninvasive investigations of brain function in various mental disorders, especially major depression, schizophrenia, and bipolar disorder. The objective of this preliminary study was to use NIRS to evaluate changes in frontal lobe blood flow in post childhood or adult patients with AD/HD symptoms. The subjects included five patients with a range of mental disorders and AD/HD symptoms, and a matched (age, sex, and dominant hand) control group of five healthy subjects. We compared the changes in cerebral blood flow during verbal fluency tasks between the two groups. The duration of the elevated oxygenated hemoglobin was notably shorter in the AD/HD group than that in the healthy control group. We suggest that the shorter elevation durations of oxygenated hemoglobin concentrations might be a biological indicator for post childhood or adult AD/HD or of impaired executive functioning.展开更多
In this paper, we consider a Gerber-Shiu discounted penalty function in Sparre Andersen risk process in which claim inter-arrival times have a phase-type （2） distribution, a distribution with a density satisfying a ...In this paper, we consider a Gerber-Shiu discounted penalty function in Sparre Andersen risk process in which claim inter-arrival times have a phase-type （2） distribution, a distribution with a density satisfying a second order linear differential equation. By conditioning on the time and the amount of the first claim, we derive a Laplace transform of the Gerber-Shiu discounted penalty function, and then we consider the joint density function of the surplus prior to ruin and the deficit at ruin and some ruin related problems. Finally, we give a numerical example to illustrate the application of the results.展开更多
基金supported in part by the Institute for Basic Science(to HP)No.IBS-R015-D1
文摘Attention deficit hyperactivity disorder（ADHD） is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients.
基金supported by the Institute for Basic Science[grant No.IBS-R015-D1]the National Research Foundation of Korea(grant No.NRF-2016R1A2B4008545)
文摘Attention deficit and hyperactivity disorder（ADHD） is a disorder characterized by behavioral symptoms including hyperactivity/impulsivity among children,adolescents,and adults.These ADHD related symptoms are influenced by the complex interaction of brain networks which were under explored.We explored age-related brain network differences between ADHD patients and typically developing（TD） subjects using resting state f MRI（rs-f MRI） for three age groups of children,adolescents,and adults.We collected rs-f MRI data from 184 individuals（27 ADHD children and 31 TD children;32 ADHD adolescents and 32 TD adolescents;and 31 ADHD adults and 31 TD adults）.The Brainnetome Atlas was used to define nodes in the network analysis.We compared three age groups of ADHD and TD subjects to identify the distinct regions that could explain age-related brain network differences based on degree centrality,a well-known measure of nodal centrality.The left middle temporal gyrus showed significant interaction effects between disease status（i.e.,ADHD or TD） and age（i.e.,child,adolescent,or adult）（P 0.001）.Additional regions were identified at a relaxed threshold（P 0.05）.Many of the identified regions（the left inferior frontal gyrus,the left middle temporal gyrus,and the left insular gyrus） were related to cognitive function.The results of our study suggest that aberrant development in cognitive brain regions might be associated with age-related brain network changes in ADHD patients.These findings contribute to better understand how brain function influences the symptoms of ADHD.
文摘OBJETTIVE: To observe the effects of Yinxingdamo Injection combined with oxiracetam capsule on cognitive function and neurological deficit in patients with acute cerebral infarction. METHODS: A total of 76 patients with acute cerebral infarction were randomly divided into observation group and control group, with 38 patients in each group. Patients in the control group were treated with conventional western medicine and oxiracetam capsules while patients in the observation group were given Yinxingdamo injection intravenous drip treatment on the basis of the same treatment. After 4 weeks of treatment, the cognitive function of the two groups before and after treatment was observed [Simple Intelligence Scale(MMSE Score), Montreal Cognitive Assessment Scale(MoCA Score)], Neurological Deficit [Chinese Stroke Scale(CSS Score), Daily Life Activity ability(ADL score)], free radical biochemical indicators [malondialdehyde(MDA), oxide dismutase(SOD)] changes, and statistical effects of two groups. RESULTS: After treatment, the total effective rate of the observation group was 92.1%, which was significantly higher than 73.7% of the control group(P < 0.05). The MMSE score and MoCA score of the two groups were significantly increased after treatment(P < 0.05), and the MMSE score and MoCA score inobservation group were significantly increased after treatment than the control group(P < 0.05). The CSS scores of the two groups were significantly decreased after treatment(P < 0.05), and the ADL scores were significantly increased(P < 0.05). The improvement of CSS score and ADL score in the observation group were significantly better than those in the control group(P < 0.05), and serum MDA levels were significantly decreased in both groups after treatment(P < 0.05), and SOD levels were significantly increased(P < 0.05), and the improvement of MDA and SOD levels in the observation group was significantly better than that in the control group group(P < 0.05). CONCLUSION: Yinxingdamo injection combined with oxiracetam capsule can effectively inhibit the oxygen free radical reaction injury in patients with acute cerebral infarction, and significantly improve the symptoms of cognitive dysfunction and neurological deficit in patients. Its curative effect is exact and worthy of clinical application.
文摘Aims: This study was designed to verify the proportion of Japanese adults with pervasive developmental disorder (PDD) who met the diagnostic criteria (other than E) for attention-deficit/hyperactivity disorder (ADHD) in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR). Furthermore, we examined to what extent adults with PDD think that they exhibit ADHD symptoms. Methods: We developed an original Japanese self-report questionnaire to determine the presence or absence of 18 symptoms from the diagnostic criteria for ADHD in the DSM-IV-TR. We administered the questionnaire to 64 adults with high-functioning PDD (45 men and 19 women) and 21 adults with ADHD (10 men and 11 women), aged 18 to 59 years, with a full-scale intelligence quotient ≥75. Target patients were evaluated for ADHD by their psychiatrists. Results: Twenty-nine (45.3%) adults with PDD also had ADHD. The percentage of these adults who had over six perceived inattention symptoms from the DSM-IV-TR was 96.6%. The percentage of these adults who had over six perceived hyperactivity-impulsivity symptoms was 65.5%. Thirty-five (55.6%) adults with PDD responded that they were aware of having ADHD symptoms at the level of the relevant diagnostic criteria. Conclusions: The present study is the first to examine the frequency of objective and perceived ADHD symptoms in adults with PDD in Japan. Our results show that both objective and perceived ADHD symptoms frequently appear in a large number of adults with PDD. This suggests that it is necessary to attend to concomitant ADHD symptoms in the medical care of adults with PDD.
文摘Background: Magnocellular deficit theory is among the different hypotheses that have been proposed to explain the pathophysiology of developmental dyslexia (DD). Dysfunction of the magnocellular system in DD has been investigated using mainly visual evoked potentials (VEPs), particularly transient VEPs, although recently abnormal steady-state VEPs have also been reported. The brain regions responsible for the abnormal VEPs in DD have yet to be elucidated, however. In this study, we performed functional magnetic resonance imaging and electroencephalography (fMRI-EEG) simultaneously to elucidate the brain areas that were found in a previous study to be activated through stimulation of the magnocellular system, and then investigated the mechanism involved in the dysfunction seen in DD.Methods: Subjects were 20 healthy individuals (TYP group;13 men, 7 women;mean ± standard deviation age, 26.3 ± 5.53 years) and 2 men with DD (aged 42 and 30 years). Images of brain activity were acquired with 3-Tesla MRI while the viewing the reversal of low-spatial frequency and low-contrast black-and-white sinusoidal gratings. EEG was recorded concurrently to obtain steady-state VEPs.Results: Stimulus frequency-dependent VEPs were observed in the posterior region of the brain in the TYP group;however, VEP amplitudes in both DD patients were clearly smaller than those in TYP. fMRI images revealed that both the primary and secondary visual cortices were activated by black-and- white sinusoidal gratings in the TYP group, whereas activity in the visual cortex overall was reduced in both DD patients.Conclusions: Present low spatial and high reversal frequency visual stimuli activated the primary visual cortex presumably through predominant activation of the magnocellular pathway. This finding indicates that some cases of adult patients of DD involve impairment of the visual magnocellular system.
文摘近年来,抑郁症(major depressive disorder,MDD)与注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)共病的现象愈发受到关注。在成人患者中,MDD共病ADHD通常意味着治疗费用高昂、药物反应欠佳以及疾病预后不良,且现有药物治疗存在一定局限性。考虑到执行功能障碍作为MDD和ADHD的关键共同特征,从执行功能层面出发,探讨共病在脑影像学方面的潜在机制,并寻求更为有效的治疗方法,显得尤为重要。近年来的研究表明,经颅直流电刺激(transcranial direct current stimulation,tDCS)作为一种能够调节特定脑区活动的非侵入性物理治疗方法,可有效改善MDD及成人ADHD的相关症状。该文回顾成人MDD共病ADHD所面临的治疗困境,从与执行功能相关的脑结构、脑功能网络等多个维度,综述成人MDD共病ADHD的可能机制,同时探讨了tDCS在治疗成人MDD共病ADHD的应用前景。
基金supported by grants from the National Natural Science Foundation of China (31460263, 30990263, and 31271171)the National Basic Research Development Program (973 Program) of China (2013CB835101)
文摘Attention deficit and hyperactivity disorder （ADHD）, a prevalent syndrome in children worldwide, is characterized by impulsivity, inappropriate inattention, and/or hyperactivity. It seriously afflicts cognitive development in childhood, and may lead to chronic under-achievement, academic failure, problematic peer relationships, and low self-esteem. There are at least three challenges for the treatment of ADHD. First, the neurobiological bases of its symptoms are still not clear. Second, the commonly prescribed medications, most showing short-term therapeutic efficacy but with a high risk of serious side-effects, are mainly based on a dopamine mechanism. Third, more novel and efficient animal models, especially in nonhuman primates, are required to accelerate the development of new medications. In this article, we review research progress in the related fields, focusing on our previous studies showing that blockade of prefrontal cortical a2A-adrenoceptors in monkeys produces almost all the typical behavioral symptoms of ADHD.
基金supported by a Project of Shanghai Municipal Health and Family Planning Commission (201540114)a Key Specialty Project of Shanghai Municipal Health and Family Planning Commission grant for Child Psychiatry (ZK2015B01)a Research Project of the Shanghai Changning Health and Family Planning Commission grant (20164Y013)
文摘The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（ADHD）, but it has been difficult to identify the mechanisms for regulating emotional problems from the understanding of ADHD comorbidity with disruptive behavior disorders（DBD）. Research based on ＂cool＇＇ and ＂hot＇＇executive functional theory and the dual pathway models,which are thought of as applied response inhibition and delay aversion, respectively, within the neuropsychological view of ADHD, has shed light on emotional responding before and after decontextualized stimuli, while CSTC circuit-related domains have been suggested to explain the different emotional symptoms of ADHD with or without comorbid DBD. This review discusses the role of abnormal connections in each CSTC circuit, especially in the emotion circuit, which may be responsible for targeted executive dysfunction at the neuroscience level. Thus, the two major domains – abstract thinking（cool） and emotional trait（hot） – trigger the mechanism of onset of ADHD.
文摘In this article, the expected discounted penalty function Фδ,α （u） with constant interest δ and ＂discounted factor＂ exp（-αTδ） is considered. As a result, the integral equation of Фδ,α （u） is derived and an exact solution for Фδ,α （0） is found. The relation between the joint density of the surplus immediately prior to ruin, and the deficit at ruin and the density of the surplus immediately prior to ruin is then obtained based on analytical methods.
文摘Prefrontal dysfunction in patients with attention-deficit/hyperactivity disorder (AD/HD) has been repeatedly detected on a behavioral level, and various brain-imaging studies have elucidated the pathophysiology of AD/HD. Recent advances in near-infrared spectroscopy (NIRS) have enabled noninvasive investigations of brain function in various mental disorders, especially major depression, schizophrenia, and bipolar disorder. The objective of this preliminary study was to use NIRS to evaluate changes in frontal lobe blood flow in post childhood or adult patients with AD/HD symptoms. The subjects included five patients with a range of mental disorders and AD/HD symptoms, and a matched (age, sex, and dominant hand) control group of five healthy subjects. We compared the changes in cerebral blood flow during verbal fluency tasks between the two groups. The duration of the elevated oxygenated hemoglobin was notably shorter in the AD/HD group than that in the healthy control group. We suggest that the shorter elevation durations of oxygenated hemoglobin concentrations might be a biological indicator for post childhood or adult AD/HD or of impaired executive functioning.
文摘In this paper, we consider a Gerber-Shiu discounted penalty function in Sparre Andersen risk process in which claim inter-arrival times have a phase-type （2） distribution, a distribution with a density satisfying a second order linear differential equation. By conditioning on the time and the amount of the first claim, we derive a Laplace transform of the Gerber-Shiu discounted penalty function, and then we consider the joint density function of the surplus prior to ruin and the deficit at ruin and some ruin related problems. Finally, we give a numerical example to illustrate the application of the results.
