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Featured researches published by Aki Johanson.


Journal of Ect | 2010

Increase in Hippocampal Volume After Electroconvulsive Therapy in Patients With Depression : A Volumetric Magnetic Resonance Imaging Study

Pia Nordanskog; Ulf Dahlstrand; Magnus R. Larsson; Elna-Marie Larsson; Linda Knutsson; Aki Johanson

Background: Major depression has traditionally been regarded as a neurochemical disease, but findings of a decreased hippocampal volume in patients with depression have turned the pathophysiological focus toward impairments in structural plasticity. The mechanisms of action of the most effective antidepressive treatment, electroconvulsive therapy (ECT), still remains elusive, but recent animal research has provided evidence for a cell proliferative effect in the hippocampus. The aim of this prospective study was to determine if hippocampal volume changes after ECT in patients with depression. Methods: Twelve patients with depression and ongoing antidepressive pharmacological treatment were investigated with clinical ratings and 3 T magnetic resonance imaging within 1 week before and after the ECT series. Each hippocampus was manually outlined on coronal slices, and the volume was calculated. Results: The left as well as the right hippocampal volume increased significantly after ECT. Conclusions: The hippocampal volume increases after ECT, supporting the hypothesis that hippocampus may play a central role in the treatment of depression.


Acta Psychiatrica Scandinavica | 2014

Hippocampal volume in relation to clinical and cognitive outcome after electroconvulsive therapy in depression

Pia Nordanskog; Magnus R. Larsson; Elna-Marie Larsson; Aki Johanson

In a previous magnetic resonance imaging (MRI) study, we found a significant increase in hippocampal volume immediately after electroconvulsive therapy (ECT) in patients with depression. The aim of this study was to evaluate hippocampal volume up to 1 year after ECT and investigate its possible relation to clinical and cognitive outcome.


Pediatric Neurology | 2014

Long-Term Cognitive Sequelae After Pediatric Brain Tumor Related to Medical Risk Factors, Age, and Sex

Ingrid Tonning Olsson; Sean Perrin; Johan Lundgren; Lars Hjorth; Aki Johanson

BACKGROUND Young age at diagnosis and treatment with cranial radiation therapy are well studied risk factors for cognitive impairment in pediatric brain tumor survivors. Other risk factors are hydrocephalus, surgery complications, and treatment with intrathecal chemotherapy. Female gender vulnerability to cognitive sequelae after cancer treatment has been evident in some studies, but no earlier studies have related this to tumor size. The purpose of our study was to find factors correlated with lowered IQ in a nationally representative sample of pediatric brain tumor patients referred for neuropsychologic evaluation. METHODS Sixty-nine pediatric brain tumor patients, diagnosed 1988-2005 and tested 1995-2006, were included in the study. In a series of stepwise multiple regressions, the relationship of IQ to disease, treatment, and individual variables (sex and syndromes) were evaluated. A subanalysis was made of the covariation between sex and tumor size. RESULTS The patients had generally suppressed IQ and impairments in executive function, memory, and attention. Lowered IQ was associated with young age at diagnosis, being male, tumor size, and treatment with whole-brain radiation therapy. A sex difference was evident for patients with increased intracranial pressure at diagnosis with males having larger tumors. Tumor size was found to be a better predictor of cognitive sequelae than sex. CONCLUSIONS Whole-brain radiation therapy, large tumors, young age at diagnosis, and male gender are risk factors for late cognitive sequelae after pediatric brain tumors. When examining sex differences, tumor size at diagnosis needs to be taken into account.


Applied Neuropsychology | 2006

Changes in frontal lobe activity with cognitive therapy for spider phobia.

Aki Johanson; Jarl Risberg; Don M. Tucker; Lars Gustafson

Patients suffering from spider phobia were studied with measurement of regional cerebral blood flow (rCBF) when they were looking at a video recording of living spiders. Six patients were studied before and after cognitive psychotherapy with successful outcome in all cases. On each occasion rCBF was measured under 3 conditions: during rest, during exposure to a video recording of neutral nature scenery, and finally while the patient watched a recording of living spiders. The patients who managed to control their emotional reactions without panicking during spider exposure before treatment showed an rCBF increase in prefrontal cortex, more pronounced in the right hemisphere. Following successful treatment, these patients showed an rCBF decrease in this region. In contrast, patients who reported panic during the initial spider exposure showed hypoactivity in the frontal cortex at that time, and then showed an increase in prefrontal rCBF in the spider challenge after cognitive therapy. The psychological improvement from cognitive therapy thus appears to be associated with activation of prefrontal cortex that varies closely with the demands for self-regulation of emotional reactivity.


Journal of Clinical and Experimental Neuropsychology | 1986

Behavioural observations during performance of the WAIS block design test related to abnormalities of regional cerebral blood flow in organic dementia

Aki Johanson; Lars Gustafson; Jarl Risberg

Twenty-one patients with symptoms of organic dementia were studied concerning the relationship between the behaviour when solving the Wechsler Block Design Test and the localization of cerebral dysfunction as indicated by the regional cerebral blood flow (rCBF). Eleven patients with decreases of rCBF in frontal regions (Group A) were compared with 10 patients with postcentral decreases (Group B). Conventional Block Design scores were about equal in the two groups. Group A patients showed significantly less anxiety and self-criticism, were less systematic and made fewer attempts at completion. Rotations were displayed more often in Group B. The results illustrate the significance of information obtained by behaviour observation in the test situation.


Scandinavian Journal of Rheumatology | 2003

Magnetic resonance imaging of the fifth metatarsophalangeal joint compared with conventional radiography in patients with early rheumatoid arthritis

K Forslind; Aki Johanson; Elna-Marie Larsson; B Svensson

Objective. To evaluate if magnetic resonance imaging (MRI) is superior to conventional radiography for detection of erosions in the fifth metatarsophalangeal (MTP5) joint. Methods. Within one year from the onset of rheumatoid arthritis (RA) (baseline), one and three years thereafter MRI and conventional radiographs of the MTP5 joint were performed in 23 patients. Results. MRI revealed erosions in 10 patients at baseline, in 15 after one year and in 15 patients after 3 years. On conventional radiography, there were erosions in 10 patients at baseline, 16 after one year as well as after 3 years. The agreement between the two imaging methods was fair to good at baseline and after one and three years (kappa 0,65, 0,51 and 0,51 respectively). The number of patients with clinical evidence of synovitis decreased considerably over time although the number of patients with MRI‐synovitis was unchanged and the number of patients with erosions increased. Conclusions. MRI was not superior to conventional radiography in detecting erosions in MTP5 joints in patients with early RA. Most erosions developed during the first year of observation. Synovitis on MRI may be a marker of future development of erosions in the MTP5 joint.


Journal of Ect | 2005

Long-Term Follow-Up in Depressed Patients Treated With Electroconvulsive Therapy.

Aki Johanson; Lars Gustafson; Jarl Risberg; Ingmar Rosén; Martin Sjöbeck; Peter Silfverskiöld

Design: Our aim was to study the long-term effects of electroconvulsive therapy (ECT) in depression. A total of 55 patients were followed-up 20 to 24 years after an ECT series; 13 patients were still alive, and 10 agreed to participate in the study. All 55 patients had been investigated with clinical and neuropsychological assessment and with neurophysiological measurements and with regional cerebral blood flow (rCBF) and EEG before the first ECT, 6 months later, and after approximately 1 year. These investigations were repeated in the 10 patients. Results: Before the original ECT series, all patients had suffered from severe mood disorder. At follow-up, the 10 patients showed no clear signs of mood disorder or cognitive impairment. There was a slightly subnormal performance in working memory and in verbal as well as visual episodic memory on all 3 occasions after the ECT series. The rCBF measurement showed a significant average CBF decrease from the first to the last measurement. There was, moreover, a significant rCBF decrease in frontal areas at the last measurement compared with the 3 previous assessments. Conclusion: All ten patients followed-up 20 to 24 years after an ECT series were mentally healthy and thus besides a moderate visual memory dysfunction, no severe side effects were observed with clinical and neuroimaging techniques.


Scandinavian Journal of Psychology | 2008

The interaction between baseline trait anxiety and trauma exposure as predictor of post-trauma symptoms of anxiety and insomnia.

Magnus R. Larsson; Martin Bäckström; Aki Johanson

In this study a prospective design was used to investigate the interaction between baseline trait anxiety and exposure to traumatic situations on post-trauma symptoms of anxiety and insomnia in a sample of Swedish peacekeeping soldiers serving in Kosovo. The result showed that pre-trauma trait anxiety interacted with exposure to traumatic situations predicting a higher post-trauma distress. Further, baseline trait anxiety and baseline symptoms of anxiety and insomnia predicted post-trauma symptoms of anxiety and insomnia. The results support a diathesis stress model in which high trait anxiety interacts with trauma exposure in the elicitation of anxiety-related distress but the study needs to be replicated before further conclusions can be drawn.


Anxiety Stress and Coping | 1992

Left orbital frontal activation in pathological anxiety

Aki Johanson; Gudmund J. W. Smith; Jarl Risberg; Peter Silfverskiöld; Don M. Tucker

Abstract Twelve patients with anxiety disorder were studied with respect to regional cerebral blood flow (rCBF) using a 32-detector system with the 133 Xe inhalation technique. Measurements were taken during a rest condition and during anxiety induction. Anxiety relevant to the patients psychological disorder was induced with a projective test, the meta-contrast technique (MCT). Increased blood flow in the orbital frontal region of the left hemisphere was observed in each of the 11 subjects who showed evidence of experiencing anxiety during the procedure. In a second study four additional anxiety patients were studied with a high-resolution (254-detector)Xe rCBF system. In addition to the anxiety and resting conditions, a neutral verbalization condition was added to control for the verbal aspects of the anxiety induction procedure. The results again showed the experience of anxiety to be accompanied by increased blood flow in the left orbital frontal region, with the patients showing this flow increase t...


Advances in psychology | 1986

Regional Changes in Cerebral Blood Flow During Increased Anxiety in Patients with Anxiety Neurosis

Aki Johanson; Jarl Risberg; Peter Silfverskiöld; Gudmund J. W. Smith

Publisher Summary This chapter investigates the changes of regional cerebral blood flow (rCBF) in anxiety-neurotic patients during experimentally controlled elevation of the state of anxiety. All the participating patients showed obvious signs of anxiety during the meta-contrast technique (MCT) test. There were also frequent behavior changes indicating anxiety when the pictures became threatening. However, none of the patients interrupted the test. During the second rCBF measurement with anxiety-activation, there were evident signs of increased anxiety in all but one patient. Vegetative symptoms, such as perspiration, restlessness, frequent swallow-movements, blushing and fast and irregular breathing were observed. Both the rCBF level and regional distribution were normal during the rest situation. The hemispheric mean flow levels did not change significantly during increased anxiety. Increased anxiety, however, was associated with regional increases of blood flow in front-temporal areas.

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