Madridge Journal of Neuroscience

ISSN: 2638-1583

International Neurology Conference

December 3-5, 2018, Valencia, Spain
Poster Session Abstracts
DOI: 10.18689/2638-1583.a1.003

Korean Medication Algorithm Project for Bipolar Disorder 2018

Won-Myong Bahk1*, Young Sup Woo1, Jong-Hyun Jeong1, Moon-Doo Kim2, Se-Hoon Shim3, Duk-In Jon4, JeongSeok Seo5 and Bo-Hyun Yoon6

1The Catholic University of Korea, Korea
2Jeju National University Hospital, Korea
3Soonchunhyang University Cheonan Hospital, Korea
4Sacred Heart Hospital, Hallym University, Korea
5Konkuk University, Korea
6Naju National Hospital, Korea

Objectives: The Korean Medication Algorithm Project for Bipolar Disorder (KMAP-BP) was first published in 2002 through an expert consensus of opinion, and updated in 2006, 2010 and 2014. This study constitutes the fourth revision of the KMAP-BP.

Methods: A 50-item questionnaire was used to obtain the consensus of experts regarding pharmacological treatment strategies for various phases of adult bipolar disorder and six items for pediatric bipolar disorder. The review committee included 84 Korean psychiatrists and 43 child and adolescent psychiatry experts.

Results: The preferred first-step strategies for acute mania were the combination of a mood stabilizer (MS) and an atypical antipsychotic (AAP), MS monotherapy, and AAP monotherapy. A combination of a MS and an AAP, and AAP monotherapy were preferredfor psychotic mania. The first-step strategies for mild to moderate bipolar depression were monotherapy with MS, AAP, or lamotrigine (LMT), and the combination of a MS and an AAP or LMT, or a combination of an AAP and LMT. The combination of two among a MS, AAP, and LMT were preferredfor non-psychotic severe depression. A combination of a MS and an AAP or thecombination of an AAP with an antidepressant or LMT were the first-line optionsfor psychotic severe depression.

Conclusion: The recommendations of the KMAP-BP 2018 have changed from the previous version by reflecting recent developments in pharmacotherapy for bipolar disorder

Biography:
Dr. Won-Myong Bahk is Head and Professor of Department of Psychiatry, Yeouido St. Maryʼs Hospital, Catholic University of Korea, and also Senior Advisor of Korean Society for Affective Disorders and Korean College of Neuropsychopharmacology, President of Korean Bipolar Disorders Forum. He has been published 136 SCI articles in such respected journals as the American Journal of Psychiatry, Journal of Affective Disorders, Journal of Clinical Psychiatry, International Journal of Clinical Psychopharmacology, and Human Psychopharmacology Clinical Experience, and 370 Korean articles, 29 medical books.

Association between Amisulpride Treatment and Dopamine D3 Receptor Gene Polymorphisms in Korean Schizophrenic Patients

Kwanghun Lee

Dongguk University, Republic of Korea

Objectives: The aim of this study is to evaluate the association between rs6280 and rs905568 genetic polymorphism of DRD3 gene and the treatment response of amisulpride.

Methods: After six weeks treatment of amisulpride, 125 schizophrenia patients were interviewed based on the Positive and Negative Syndrome Scale (PANSS) and the Clinical Global Impression-Severity (CGI-S). The genotyping for rs6280 and rs905568 was performed using TaqMan single nucleotide polymorphism (SNP) genotyping assay.

Results: There was no significant difference in the frequency of genotype and allele of rs6280 between the responders and nonresponders based on the total, positive, and general score of PANSS and CGI-S score. However, there was a significant association between this SNP and treatment response in the negative score of PANSS (χ2 = 5.23, p = 0.022). There was no significant association between rs905568 and the response in positive, negative, general, and total PANSS score and CGI-S score.

Conclusions: This is the first positive association study between DRD3 gene and the treatment response of negative symptoms to amisulpride in Korean schizophrenia patients. A larger scale research on more SNP of the DRD3 gene will make a progress in the study of pharmacogenetics on the treatment response of the amisulpride.

Keywords: Treatment response, Amisulpride, DRD3 gene, Polymorphisms rs6280.

Biography:
Dr. Kwanghun Lee is Chair of Department of Psychiatry, Dongguk university hospital, Gyeongju, Republic of Korea President of Korean Society of Biological therapies in psychiatry, Board member of directors of KCNP.

Psychopharmacological Treatment Patterns in Patients with Schizophrenia and Schizoaffective Disorder in Forensic Inpatient Settings

Dae Bo Lee1*, Won-Myong Bahk2, Bo-Hyun Yoon3, Sang-Yeol Lee4, Duk-In Jon5, Moon-Doo Kim6, Kwang Huen Lee7, Beomwoo Nam8, Young-Min Park9 and Young-Joon Kwon10

1National Forensic Hospital, Republic of Korea
2The Catholic University of Korea, Republic of Korea
3Naju National Hospital, Republic of Korea
4Wonkwang University Hospital, Republic of Korea
5Hallym University, Republic of Korea
6Jeju National University, Republic of Korea
7Dongguk University, Republic of Korea
8Konkuk University, Republic of Korea
9Inje University College of Medicine, Republic of Korea
10DepaSoonchunhyang University, Republic of Korea

Objective: The National Forensic Hospital is the only forensic psychiatric hospital in Korea. As of January 2016, the average number of patients assigned to each psychiatrist is more than 120. In this situation, the role of psychopharmacologic treatment becomes very important.

Methods: To investigate the prescription patterns of major psychotropic medications (i.e., antipsychotics, mood stabilizers, and antidepressants), we reviewed the medical records of the patients diagnosed with schizophrenia and schizoaffective disorder who were admitted in January 2016.

Results: The data from 418 patients (403 with schizophrenia and 15 with schizoaffective disorder) were retrospectively collected and analyzed. The average number of major psychotropic medications prescribed for each patient during hospitalization was as follows: antipsychotics, 3.5±1.8 mood stabilizers, 0.5±0.7 and antidepressants, 0.5±0.8. The three most frequently prescribed antipsychotics were risperidone (21.7%), olanzapine (15.5%), and quetiapine (14.4%). More than half of the patients (233, 55.9%) were prescribed an antipsychotic polypharmacy regimen.

Conclusion: This study found that patients with schizophrenia and schizoaffective disorder in forensic psychiatric hospital tend to be prescribed many psychotropic medications.

Keywords: Schizophrenia, Forensic psychiatry, Prescribing pattern, Psychopharmacology, Polypharmacy.

A Study of Anger and Alexithymia in Korean Patients with Tension-type Headache

Sang Yeol Lee

Wonkwang University School of Medicine, Korea

Background: Tension-type headache is a commonly encountered disturbance of neurology and psychiatry and it has been shown to be associated with psychological factors or disturbance such as depression and anxiety. Of particular importance to clinicians are the relationship between anger and alexithymia. In this study, we investigated anger and alexithymia in Korean patients with tensiontype headache.

Methods: The subject were 30 patients with tension-type headache diagnosed by neurologist and psychiatrist, and they were compared to 30 healthy control group. The results of medical investigation of patients including brain CT and EEG were negative. All subjects were evaluated for depression, anxiety, anger and anger expression and alexithymia. The measures included Beck Depression Inventory (BDI), Spielberger State-Trait Anxiety Inventory (STAI), Spielberger State-Trait Anger Expression Scale (STAXI), and Toronto Alexithymia Scale (TAS).

Results: The patient with tension-type headache reported significantly more symptoms of depression, more difficulty describing feeling to other in TAS, less anger-in and anger-out expression in STAXI than the control subjects. Depressive symptoms in patients with tension headache were positively correlated with state anxiety, trait anxiety, alexithymia, state anger and anger-in expression.

Conclusion: These finding lend support that tension-type headache is associated with affect dysregulation and it may play role in features of tension headache. Psychosomatic assessment and treatment of patients with tension-type headache will be needed.

Subclinical Hypothyroidism and Incident Depression in Young and Middle Age Adults

Sehoon Shim1* and Won-Myong Bahk2

1Soonchunhyang University Cheonan Hospital, South Korea
2The Catholic University of Korea, Korea

Background: The role of subclinical hypothyroidism in the development of depression remains controversial. We examined the prospective association between subclinical hypothyroidism and incident depressive symptoms.

Methods: We conducted a prospective cohort study in 220,545 middle age adults without depression who underwent at least 2 comprehensive health exams between January 1, 2011 and December 31, 2014. Thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxin (FT4) levels were measured by an electrochemiluminescent immunoassay. The study outcome was incident depressive symptom defined as a CES-D score >16.

Results: During a median follow-up of 2 years, incident depressive symptoms occurred in 7,323 participants. The multivariableadjusted hazard ratio (HR) for incident depressive symptoms comparing subclinical hypothyroid to euthyroid participants was 0.97 (0.87 to 1.09). Similarly, among euthyroid participants (n = 87,822), there was no apparent association between thyroid hormone levels and increased risk of incident depressive symptoms. Discussion: There was no apparent association between subclinical hypothyroidism and incident depressive symptoms in a large prospective cohort of middle-aged men and women.

Korean Medication Algorithm for Bipolar Disorder: Changes in Preferred Medications for Mania Over 16 Years

Duk-In Jon1*, Jeong-Seok Seo2, Bo-Hyun Yoon3, Kyung Joon Min4 and Won-Myong Bahk5

1Hallym University Sacred Heart Hospital, Korea
2Konkuk University Chungju Hospital, Korea
3Naju National Hospital, Korea
4Chung-Ang University Hospital, Korea
5The Catholic University of Seoul, Korea

Introduction: Many treatment guidelines for bipolar disorders have been introduced to assist clinical decision. Majority of these guidelines are based on evidences from clinical trials. The Korean Medication Algorithm Project for Bipolar Disorder (KMAP-BP) was developed to adopt and maintain an expert-consensus paradigm which was more practical and specific to the atmosphere in Korea. In this research, preferred medication strategies for acute mania over four consecutively published KMAP-BP guidelines (2002, 2006, 2010, 2014, and 2018) were investigated.

Methods: The KMAP-BP questionnaire using a nine-point scale had covered some specific clinical situations divided into subsections with many treatment options. A written survey asked about the appropriateness of various treatment strategies and agents.

Results: The most preferred initial treatment strategy for all subtypes of mania was a combination of mood stabilizer (MS) and atypical antipsychotic (AAP) in every edition. In contrast to MS monotherapy, the preference of combination therapy has been increased over time. Among MSs, lithium and valproic acid are almost equally preferred except in the mixed subtype where valproic acid is the most recommended MS. Olanzapine, quetiapine, and aripiprazole were the preferred AAP for acute mania in later editions. This change might depend on the recent research results and safety profile. In cases of unsatisfactory response to the firstline medications, we recommended switching or adding another first-line agent.

Discussion: The Korean experts have been increasingly convinced of the effectiveness of a combination therapy for manic episode. There have been evident preference changes: increased for AAP and decreased for carbamazepine.

Biography:
Dr. Duk-In Jon is the Professor and Chairman of Department of Psychiatry, Hallym University Sacred Heart Hospital in Korea, Vice President in the Korean Society for Affective Disorders, Editor-in-chief of Clinical Psychopharmacology and Neuroscience (SCIE).

Psychological Burden of Myasthenia Gravis

Beomwoo Nam

Konkuk University, Republic of Korea

Myasthenia gravis (MG) is an autoimmune disorder affecting neuro-muscular transmission. Although MG patients suffering from their muscle weakness and its related psychological symptoms, few studies have been done to measure the psychological burden quantitatively imposed by MG. Therefore, we sought to assess several aspects of psychological distress of MG patients quantitatively and compare them to normal healthy controls in the 19-year-old military candidates. In Korea, a conscription system has been adopted, wherein all men 19 years old and over have military duty. Before joining the army, all men undergo evaluations of physical and psychological status by clinicians from all departments of the Military Manpower Administration (MMA). Among them, we reviewed 988, 720 medical records of Korean military candidates aged 19 years from February 2010 to January 2013. MG was diagnosed by neurologists based on the results of acetylcholine receptor antibody test, repetitive nerve stimulation test, or clinical manifestations in the hospitals and MMAs. Psychological distress was evaluated using Korean Military Multiphasic Personality Inventory (MPI). We controlled the variables for age, sex, and race-ethnicity (19-year-old men in Korea). MG patients reported significantly lower level of faking good scale (t = 2.564, p = 0.012) among validity scales and significantly higher level of somatization scale (t = -2.340, p = 0.021) among neurosis scales and showed increasing tendency of anxiety scale(t = -1.826, p = 0.070), with no statistical significance. We estimated psychological burden of MG in the 19-year-old military candidates in Korea. Less faking good attitude, higher level of somatization scale and increasing tendency of anxiety scale of MG patients may represent psychological distress burdened by MG. It is not yet apparent whether psychological distress is related to the illness-related symptoms or psychiatric vegetative signs.

Decreased Quality of Life in Elderly Patients with Subsyndromal Depression

Moon-Doo Kim1*, Young-JoonKwon 2, Bo-HyunYoon3 and Won-Myong Bahk4

1Jeju National University Hospital, Korea
2Soonchunhyang University Chun-An Hospital, Korea
3Naju National Hospital, Korea
4The Catholic University of Korea, Korea

Objectives: Non-major depression with fewer symptoms than required for a DSM-IV diagnosis of major depressive disorder (MDD) has consistently been found to be associated with functional impairment. In this study, we aim to estimate the quality of life in elderly patients with subsyndromal depression (SSD) compared with non-depressive elderly (NDE).

Methods: The Korean version of Mini International Neuropsychiatric Interview was administered to 194 of outpatients with depression and 108 of normal control group. SSD is defined as having five or more current depressive symptoms with core depressive symptoms (depressive mood or loss of interest or pleasure) during more than half a day and more than seven days over two weeks. Depression was evaluated by the Korean form of Geriatric Depression Scale of a 15-item short version (KGDS-15). Global cognition was assessed by the Korean Version of Revised form of Hasegawa Dementia Scale (K-HDS) and Mini-Mental State Examination in the Korean version of CERAD assessment packet (MMSE-KC). Subjective cognitive impairment was assessed Subjective Memory Complain Questionnaire (SMCQ). Quality of life was evaluated by The Korean Version of Short-Form 36-Item Health Survey (SF-36).

Results: The scores of physical component summary (PCS)(F=9.274, p=0.003, ANCOVA) and mental component summary (MCS) (F=53.166, p<0.001, ANCOVA) in the SSD group were lower than those in NDE group with adjustment for age, gender, and education(by SF-36)

Conclusion: Subjects with SSD, as well as those with MDD, were experienced low quality of life in both physical and mental aspects, compared to NDE group.

Biography:
Prof. Kim is working on Jeju National University Hospital and graduated Kyungpook National University, College of Medicine. Also He graduated PhD. course in Kyungpook National University, College of Medicine. He has worked at UCLA Neuropsychiatric Institute as visiting scholar. He is interested in mood disorder, psychopharmacology and neuroscience

Difference in Treatment Outcome in Hospitalized Major Depression Patients with Versus without Anxious Distress Specifier in DSM-5

Won-Myong Bahk1*, Young Sup Woo1, In Hee Shim2, Moon-Doo Kim3, JeongSeok Seo4 and Bo-Hyun Yoon5

1The Catholic University of Korea, Korea
2Dongnam Institute of Radiological & Medical Sciences, Korea
3Jeju National University Hospital, Korea
4Konkuk University, Korea
5Naju National Hospital, Korea

Objectives: In Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), a new specifier of major depressive disorder (MDD) “with anxious distress” allowscharacterization of additional symptoms. The aim of this study was to investigate difference in treatment outcome of MDD with versus without anxious distress specifier in DSM-5.

Methods: Retrospective chart review of patients admitted to a university hospital with a primary diagnosis of MDD. We reviewed anxious distress symptoms, medications and detailed clinical information at index episode. We compared treatment outcomes of anxious distress group with those of non anxious distress group.

Results: There were differences in remission rate after 4 weeks later (18.5% vs. 44.4%, p=0.040) and at discharge (33.3% vs. 66.7%, p=0.014) between anxious distress and non anxious distress. However, no significant differences were observed in the sociodemographic characteristics, treatment regimens, and response rate.

Conclusion: Anxious distress specifier might be worthwhile to be further evaluated as a diagnostic entity of its own requiring specific diagnosis and therapeutic attention. Korean J Psychopharmacol 2015;26(1):22-28

Biography:
Dr. Won-Myong Bahk is Head and Professor of Department of Psychiatry, Yeouido St. Maryʼs Hospital, Catholic University of Korea, and also Senior Advisor of Korean Society for Affective Disorders and Korean College of Neuropsychopharmacology, President of Korean Bipolar Disorders Forum. He has been published 136 SCI articles in such respected journals as the American Journal of Psychiatry, Journal of Affective Disorders, Journal of Clinical Psychiatry, International Journal of Clinical Psychopharmacology, and Human Psychopharmacology Clinical Experience, and 370 Korean articles, 29 medical books.

Relationship between Tnf-α and Central Serotonergic Activity using Scalp and Source Analysis of Auditory Evoked Potentials in Patients with Major Depressive Disorder

Young-Min Park2*, Bun-Hee Lee1, Seung-Hwan Lee2,3 and Miseon Shim4

1Maum & Maum Psychiatric Clinic, Republic of Korea
2Inje University College of Medicine, Republic of Korea
3Inje University, Republic of Korea
4University of Missouri-Kansas City, United States

Rationale: Proinflammatory cytokines such as TNF-α can induce major depressive disorder (MDD). Some studies have assumed that TNF-α is associated with tryptophan depletion and finally result in MDD with low serotonergic activity. However, another studies revealed TNF-α increased serotonin firing in raphe and serotonergic activity. Therefore, it is still unclear whether TNF-α increases or decreases the serotonin activity.

Objectives: The aim of this study was therefore to determine the relationship between TNF-α and central serotonergic activity using the loudness dependence of auditory evoked potentials (LDAEP).

Methods: Scalp and standardized low-resolution brain electromagnetic tomography (sLORETA)-localized auditory evoked potentials and TNF-α were evaluated in 64 MDD outpatients with mild-moderate severity at baseline. The Beck Depression Inventory (BDI), Hamilton Depression Rating Scale, Hamilton Anxiety Scale, Beck Scale for Suicidal Ideation, Beck Hopeless Scale, and Barrett Impulsity Scale (BIS) werewere also applied to them. They were dichotomized according to the median TNF-α level into low- and high-TNF-α groups.

Results: The mean BDI and BIS scores were higher in the high-TNF-α group than in the low-TNF-α group. In addition, the average P2 LDAEP, left N1 sLORETA-LDAEP, left P2 sLORETA-LDAEP, average P2 sLORETA-LDAEP, left N1/P2 sLORETA-LDAEP, and average N1/P2 sLORETA-LDAEP were lower in the high-TNF-α group than in the low-TNF-α group. When multiple binary logistic regression analysis for TNF-α was carried, the relationship between TNF-α and N1/P2 sLORETA-LDAEP was also significant.

Conclusions: This study supports that TNF-α can increase the central serotonin activity in outpatients with MDD of mild-to-moderate severity.

Biography:
Dr. Young-Min Park is associate professor, Department of Psychiatry, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Republic of korea (South Korea). He is graduated from Korea University College of Medicine, Seoul. Resident training in psychiatry was conducted at Korea University College of Medicine, Anam Hospital. Clinical instructor, instructor and assistant professor of Department of Psychiatry in Inje University College of Medicine, Ilsan Paik Hospital. His research interest are in mood disorder and sleep disorder.

Factors Associated with Bullying Victimization among Adolescents in Jeju Island of Korea

Young-Joon Kwon

Soonchunhyang University Chun-An Hospital, Korea

Purpose: The aim of the present study is to assess the prevalence of bullying victimization among Korean adolescents and to investigate the correlates.

Methods: Of a total of 3,200 eligible subjects, 2,936 (91.8%) adolescents were recruited from four elementary schools (6th grade, age range: 11-12 years), five middle schools (8th grade, age range: 13-14 years) and three high schools (10th grade, age range: 15-18 years) located in the Jeju Special Self-Governing Province, Republic of Korea. This study used a self-reported questionnaire concerning sociodemographic factors and experience of bullying victimization, and the Korean form of Childrenʼs Depression Inventory (CDI) for depressive symptoms. This study was approved by the Jeju National University Hospital Review Board.

Results: Among the total 2936 students, there were 1689 boys (57.5%) and 1247 girls (42.5%). The mean ± standard deviation age was 13.83 ± 1.42 years. The prevalence of bullying victimization was 8.2% (n=240). Bullying victimization was significantly associated with girls (OR=1.775, p<0.001), lower age (OR=0.868, p=0.008), lower SES (OR=1.666, p=0.033), lower than average academic achievement (OR=1.765, p=<0.0010), more depressive symptoms (OR=1.877, p<0.001) and poorer perceived relationship with parents (OR=1.462, p=0.049) in multivariate logistic analysis.

Conclusions: Our findings will provide scholars and public health practitioners information on the prevalence and correlates of bullying victimization that is a risk factors for later behavioral and emotional problems.

Keywords: Bullying, Adolescents, Risk factors, Korea

Prevalence of Sleep Problems and Its Impact on Anxiety, Depression and Quality of Life in Korean Fire Fighters

Sang Yeol Lee

Wonkwang University School of Medicine, Korea

Background: Professional fire fighter is a strenuous and unique occupation due to the high levels of stress and risk involved as well as the low control nature of the job. Anxiety and depression are prevalent in the professional fire fightersʼ population and constitute a dominant area of investigation. Limited attention have been given to impact of sleep problems on the anxiety, depression and quality of life in fire fighters. The aim of this study is to evaluate prevalence of sleep problems and its impact on anxiety, depression and quality of life in Korean fire fighters.

Methods: Using simple sampling method in a cross-section study in Jeonbuk province of Korea, sleep problems, anxiety, depression and quality of life of 1669 professional fire fighters were measured with Patients Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder 7 item (GAD-7) and brief version of World Health Organization Quality of Life assessment scale (WHOQoL-Brief). Sleep problem was measured with 3 item of PHQ-9, the definition of sleep problems group was not able to initiate sleep or maintaining sleep. We measured cross-sectional Odds ratios for sleep problems group on depression and anxiety by logistic regression analysis.

Results: The prevalence of sleep problem of Korean fire fighters was 51.2%. Korean fire fighters with sleep problems showed not only more anxiety (p<0.001) and depression(p<0.001) but also lower quality of life (p<0.001). The sleep problems group was more likely to suffer from depression (OR=47.537,95%, Cl: 33.669- 64.323) and anxiety (OR=9.822, 95%, Cl: 7.529-12.813). The severity of sleep problems in Korean fire fighters was positive correlated with depression and anxiety.

Conclusion: These results show that higher prevalence of sleep problems in Korean fire fighters and Korean fire fighters with sleep problems have more depression and anxiety, and less quality of life than fire fighters with\-out sleep problems. Sleep problems are important risk factor on the depression and anxiety in Korean fire fighters. Early detect of sleep problems of fire fighters will be needed to manage of depression and anxietyʼ.

Keywords: Insomnia, Prevalence, Anxiety, Depression, QoL, Fire fighter.

Dance-like Movement of an Attempted Murderer? A Case Report

Dae Bo Lee1*, Won-Myong Bahk2, Bo-Hyun Yoon3, Sang-Yeol Lee4, Duk-In Jon5, Moon-Doo Kim6, Kwang Huen Lee7, Beomwoo Nam8, Young-Min Park9 and Young-Joon Kwon10

1National Forensic Hospital, Republic of Korea
2The Catholic University of Korea, Republic of Korea
3Naju National Hospital, Republic of Korea
4Wonkwang University Hospital, Republic of Korea
5Hallym University, Republic of Korea
6Jeju National University, Republic of Korea
7Dongguk University, Republic of Korea
8Konkuk University, Republic of Korea
9Inje University College of Medicine, Republic of Korea
10DepaSoonchunhyang University, Republic of Korea

Huntingtonʼs disease (HD) is a rare, fatal inherited disorder that results from excessive repetition of the trinucleotide sequence CAG (cytosine-adenine-guanine) in the Huntingtonʼs disease gene on the short arm of Chromosome 4. Huntingtonʼs disease is characterized by the triad of symptoms: motor, cognitive, and psychiatric disturbances. Among them, the motor disturbance includes chorea, slurred speech, problems with balance, and dysphagia. Because forensic evaluators are highly likely to encounter the malingering, they must keep in mind the possibility of malingering and/or minimization or exaggeration of symptoms. If the evaluators does not thoroughly assess because of excessive preconceptions, the likelihood of misdiagnosis might be increased. The author will describe a 48-years old woman who attempted murder and manifested chorea in all limbs, dysarthria, and dysphagia, and discuss a diagnostic process of the case with HD.

Keywords: Huntingtonʼs disease.

Subthalamic Nucleus Single-Unit Activity during a Preference-Based Decision-Making Task

T.M. Alozzi1,2*, L.F. Botero Posada3, A.L. Lopez Rios3 and W.D. Hutchison1,2,3

1University of Toronto, Canada
2Toronto Western Research Institute, Canada
3Hospital Universitario De San Vicente FundaciÓn, Colombia

Parkinsonʼs disease patients often present with cognitive deficits (prevalence: approximately 40%), besides the better-known motor and mood deficits. Following subthalamic nucleus deep brain stimulation (STN-DBS) patients may showcognitive decline as measured by verbal fluency and post-op MoCA test, but it is not known whether the STN is directly involved. To further understand the specific role of the STN in cognitive processes as well as to localize these functions within the STN, we monitored single unit activity during a preference-based decision-making task intraoperatively.

Microelectrode recordings were made from tracks passing through the STN of patients undergoing bilateral implantation of DBS electrodes. Two electrodes (2mm apart) were advanced and stable baseline STN activity was recordedfollowed by a preference-based decision-making task. The task consisted of 5 animal pictures with 2 pictures presented at a time, in random order. Patients were asked to pick their favorite picture each time by clicking the mouse button that corresponds to the preferred picture (e.g. right click for right picture). Once a click was made there was a 500ms blank screen delay period before the next 2 pictures showed up. Each trial consisted of 50-75 picture presentations. After the experiment was done patients were asked to rank the 5 animals on a scale of most favorite to least favorite. Results were analyzed offline using Spike2 (CED).

A total of 20 neurons from 7 PD patients and 12 different trials was analyzed (n=7). 9/12 trials were recorded from the dorsal two-thirds of the STN and 3/12 trials were recorded from the ventral third of the STN. At baseline, STN cells fired at 42.7 +/- 6.6 (+/- SEM). The 20 neurons analyzed behaved differently in response to different picture presentations. 9 neurons showed a visuosensory response (short latency increase in firing rate) to the favorite picture 0-0.2ms after the pictures were presented. 11 neurons showed an inhibitory response (short latency decrease in firing rate) to the favorite picture 0.3-0.5ms after the pictures were presented. 3 neurons showed an excitatory response to the favorite picture with a latency of 0.3-0.5ms. 6 neurons showed no response to the favorite picture presentation. All neurons tested did not respond to the non-favorite pictures. Although these are preliminary results, the subthalamic nucleus seems to be directly modulated by cognitive processes such as visual preference, and this modulation seems to be present throughout the dorsoventral extent of the STN.