Electroencephalography changes during change blindness disorder

Background/objective: the electroencephalogram [EEG] is the process of recording electrical potentials produced by neurons in the brain. For understanding the neuro-physiological mechanism of various cognitive and neurological disorders, EEG has been proved a vital technique for many years. The change blindness which is incapability of brain to notice substantial visual changes is among such disorders. This study investigates the complexity in information process of EEG signals during the change blindness disorder using the two different measures called entropy and correlation dimension functions

Methods: the EEG data of change blindness disorder was recorded from 22 subjects while they were performing change detection and change blindness trials for two types of stimuli. These were [1] single stimulus followed by another matching stimulus, [2] single stimulus followed by another non-matching stimulus. The measure of complexity in recorded EEG was estimated using both correlation dimension and approximate entropy functions

Results: the results have shown significant decrease in values of approximate entropy and correlation dimension at frontal position of electrodes for change blindness trials

Conclusion: the neurophysiological implication of these results provide the possibility that the increase of brain complexity, which can be interpreted as increase of information process and integration, was not sustained in frontal position of brain during the change blindness disorder

Correlation of Urdu version of hospital anxiety depression scale and Hamilton depression rating scale in quantifying depression among post-myocardial infarction patients

Objective: to validate the use of Urdu Version of Hospital Anxiety Depression Scale as screening as well as quantifying tool for depression among non-psychiatric hospital population

Material and methods: this retrospective study was conducted at National Institute of Cardiovascular Disease [NICVD] Karachi and Civil Hospital Karachi [CHK] from 23rd October to 22nd November 1998. We searched the record of a previous study on the patients on myocardial infarction. A comparison of scores of Hospital Anxiety Depression Scale and Hamilton Depression Rating Scale, done on the patients with first myocardial infarction at an interval of about two weeks during hospitalization and after their discharge, was made

Results: correlation co-efficient between Hospital Anxiety Depression Scale scores and Hamilton Depression Rating Scale scores was found to be statistically significant [r =55; p<0.001]

Conclusion: results suggest that Hospital Anxiety Depression Scale can be used as an effective tool to screen and quantify depression

Frequency of anxiety and depression in migraine - a study of 102 patients

Objective: The study was aimed to see the frequency of Anxiety and Depression among patients with Migraine. Design: Cross sectional study. Setting: Department of Psychiatry, Abbasi Shaheed Hospital Karachi and Department of Psychiatry Ziauddin University Hospital, KDLB campus, Kemari Karachi Duration: 1[st] June 2007 to 30[th] November 2007

Methods: Referred patients of headache diagnosed as suffering from migraine were selected for the study. Diagnosis of migraine was based on the criteria for migraine designed by International Headache Society. Patients were enrolled irrespective of age and sex. Only those patients were included who fulfilled the selection criteria. Any routine or relevant investigations wherever required were carried out. Following selection of the cases, the patients were administered the Hospital Anxiety and Depression Scale, Urdu version. All the findings were recorded on a preformed Proforma. The data were compiled, tabulated and analyzed using SPSS version 10

Results: One hundred and two patients with migraine comprising 65 females [63.8%] and 37 males [36.2%], minimum age of presentation 11 years and maximum 71 years completed the study. Majority of the patients [75%] aged between 20 and 50 years. On screening for psychiatric caseness using the validated Urdu Version of Hospital Anxiety and Depression Scale with a cutoff score of 11-21 for both anxiety and depression 58 patients [56.8%] had psychiatric morbidity. Therefore, 44 patients [43.1%] were not positive for psychiatric caseness. Of the 58 patients with positive psychiatric caseness, there were 23 males 40%] and 35 females [60%]. These included 25 patients [43%] with anxiety, 18 patients [31%] of depression while 15 patients [26%] had both anxiety and depression. Eighty percent of the 58 patients with positive psychiatric caseness aged between 20-50 years

Conclusion: Migraine has a significant association with anxiety and depression. Frequency of this association may be influenced by sex and age