1
|
Yun JY, Jin MJ, Kim S, Lee SH. Stress-related cognitive style is related to volumetric change of the hippocampus and FK506 binding protein 5 polymorphism in post-traumatic stress disorder. Psychol Med 2022; 52:1243-1254. [PMID: 32892762 DOI: 10.1017/s0033291720002949] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Patients with post-traumatic stress disorder (PTSD) show a different stress-related cognitive style compared with healthy controls (HC). The FK506 binding protein 5 gene (FKBP5), one of the PTSD known risk factors, is involved in the stress response through the hypothalamic-pituitary-adrenal axis and brain volumetric alterations. The present study aimed to uncover the neural correlates of stress-related cognitive styles through the analysis of the regional brain volumes and FKBP5 genotype in patients with PTSD compared with HC. METHODS In this study, 51 patients with PTSD and 94 HC were assessed for stress-related cognitive styles, PTSD symptoms severity, and genotype of FKBP5 single nucleotide polymorphisms, and underwent T1-weighted structural magnetic resonance imaging. Diagnosis-by-genotype interaction for regional brain volumes was examined in 16 brain regions of interest. RESULTS Patients with PTSD showed significantly higher levels of catastrophizing, ruminative response, and repression, and reduced distress aversion and positive reappraisal compared with HC (p < 0.001). Significant diagnosis-by-genotype interactions for regional brain volumes were observed for bilateral hippocampi and left frontal operculum. A significant positive correlation between the severity of the repression and left hippocampal volume was found in a subgroup of patients with PTSD with FKBP5 rs3800373 (AA genotype) or rs1360780 (CC genotype). CONCLUSIONS The present study showed the influences of FKBP5 genotype on the distorted cognitive styles in PTSD by measuring the volumetric alteration of hippocampal regions, providing a possible role of the hippocampus and left frontal operculum as significant neurobiological correlates of PTSD.
Collapse
Affiliation(s)
- Je-Yeon Yun
- Seoul National University Hospital, Seoul, Republic of Korea
- Yeongeon Student Support Center, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Min Jin Jin
- Department of Psychiatry, Wonkwang University Hospital, Iksan, Republic of Korea
- Institute of General Education, Kongju National University, Gongju, Republic of Korea
| | - Sungkean Kim
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Seung-Hwan Lee
- Clinical Emotion and Cognition Research Clinical Emotion and Cognition Research Laboratory, Inje University, Goyang, Republic of Korea
- Department of Psychiatry, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Republic of Korea
| |
Collapse
|
2
|
Luo Y, Lei D, Li L, Suo X, Hu X, Wen J, Wang X, Meng Y, Yu J, Sun X, Huang Y, Gong Q. WITHDRAWN: Changes of regional cortical thickness in children with post-traumatic stress disorder—A magnetic resonance imaging study. IBRO Rep 2020. [DOI: 10.1016/j.ibror.2020.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
3
|
Galadari A. Psychology of Mystical Experience: Muḥammad and Siddhārtha. ANTHROPOLOGY OF CONSCIOUSNESS 2019. [DOI: 10.1111/anoc.12116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
4
|
Borg C, Faillenot I, Peyron R, Laurent B. Retrieving autobiographical experience of painful events in a phantom limb: brain concomitants in a case report. Neurocase 2018; 24:41-48. [PMID: 29388508 DOI: 10.1080/13554794.2018.1429636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We report the case of a patient who had an important experience with painful events, allowing the investigation of brain concomitants to painful (P) memories in fMRI. The patient had to recall P events that were contrasted with non-painful (NP) memories. Painful memories of the right lower limb activated the left paracentral lobule,fronto-insular operculum and superior parietal cortex. Additionally, whilst the recall of non-painful events activated the hippocampus, the recall of painful events did not enhance the hippocampal signal to significant levels. These suggest that brain activations differ for the autobiographical recall of painful and non-painful memories.
Collapse
Affiliation(s)
- Céline Borg
- a Neurology/Neuropsychology CMRR Unit , CHU Nord Saint-Etienne , Saint-Priest-en-Jarez , France.,b Psychology Department , University of Lyon , Lyon , France.,c Study of Cognitive Mechanisms Laboratory , University of Lyon , Bron , France
| | - Isabelle Faillenot
- a Neurology/Neuropsychology CMRR Unit , CHU Nord Saint-Etienne , Saint-Priest-en-Jarez , France.,d CNRL, INSERM U1028; UCB Lyon1 , University Jean Monnet , Saint-Etienne , France
| | - Roland Peyron
- d CNRL, INSERM U1028; UCB Lyon1 , University Jean Monnet , Saint-Etienne , France.,e Pain Center , CHU Nord Saint-Etienne , Saint Priest-en-Jarez , France
| | - Bernard Laurent
- a Neurology/Neuropsychology CMRR Unit , CHU Nord Saint-Etienne , Saint-Priest-en-Jarez , France.,d CNRL, INSERM U1028; UCB Lyon1 , University Jean Monnet , Saint-Etienne , France.,e Pain Center , CHU Nord Saint-Etienne , Saint Priest-en-Jarez , France
| |
Collapse
|
5
|
Hulbert JC, Henson RN, Anderson MC. Inducing amnesia through systemic suppression. Nat Commun 2016; 7:11003. [PMID: 26977589 PMCID: PMC4796356 DOI: 10.1038/ncomms11003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 02/10/2016] [Indexed: 11/09/2022] Open
Abstract
Hippocampal damage profoundly disrupts the ability to store new memories of life events. Amnesic windows might also occur in healthy people due to disturbed hippocampal function arising during mental processes that systemically reduce hippocampal activity. Intentionally suppressing memory retrieval (retrieval stopping) reduces hippocampal activity via control mechanisms mediated by the lateral prefrontal cortex. Here we show that when people suppress retrieval given a reminder of an unwanted memory, they are considerably more likely to forget unrelated experiences from periods surrounding suppression. This amnesic shadow follows a dose-response function, becomes more pronounced after practice suppressing retrieval, exhibits characteristics indicating disturbed hippocampal function, and is predicted by reduced hippocampal activity. These findings indicate that stopping retrieval engages a suppression mechanism that broadly compromises hippocampal processes and that hippocampal stabilization processes can be interrupted strategically. Cognitively triggered amnesia constitutes an unrecognized forgetting process that may account for otherwise unexplained memory lapses following trauma.
Collapse
Affiliation(s)
- Justin C Hulbert
- Bard College, Psychology Program, PO Box 5000, Annandale-on-Hudson, New York 12504, USA
| | - Richard N Henson
- Medical Research Council, Cognition and Brain Sciences Unit, 15 Chaucer Road, Cambridge CB2 7EF, UK
| | - Michael C Anderson
- Medical Research Council, Cognition and Brain Sciences Unit, 15 Chaucer Road, Cambridge CB2 7EF, UK.,Behavioural and Clinical Neurosciences Institute, Sir William Hardy Building, Downing Street, University of Cambridge, Cambridge CB2 3EB, UK
| |
Collapse
|
6
|
Abstract
Emotional factors are an obstacle in the diagnosis and management of asthma. This review discusses three problem patterns: negative emotions in relatively normal patients with asthma; patients presenting possible functional symptoms and; patients presenting asthma in conjunction with psychiatric deviations. Negative emotions influence the symptoms and management of asthma, even in relatively normal patients. Psychogenic symptoms appear normal, but culminate in functional symptoms in a minority of patients. Diagnosing and treating asthma in patients with comorbid asthma and psychiatric symptoms is very difficult. On the one hand, treating asthma may often be just treating the emotions. On the other hand, negative emotions make the treatment of asthma guesswork. Physicians should estimate emotional influences in their patients' symptoms for an optimal evaluation of medication efficacy. Assessment and analysis of emotional factors surrounding exacerbations seems essential, e.g. emotional precipitants of asthma and asthma-evoked negative emotions. Moreover, patients should be informed about stress-induced breathlessness and the consequences of overuse of bronchodilators. When patients present with atypical symptoms, or do not properly respond to asthma medication, functional symptoms should be suspected. Psychiatric analysis may often lead to the conclusion that symptoms have a functional basis. In patients with comorbid asthma and anxiety disorders, asthma should be the focus for treatment since difficult-to-control asthma often causes anxiety problems in the first place. Moreover, panic-like symptoms in asthma are often related to sudden onset asthma exacerbations. However, in patients with comorbid asthma and depression, depression should become the focus of treatment. The reason is that optimal treatment of depressive asthmatics is probably impossible. Special issues include specific problems with children, compliance problems, and physicians' dilemmas regarding the simultaneous treatment of asthma and psychiatric symptoms.
Collapse
Affiliation(s)
- Simon Rietveld
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands.
| | | |
Collapse
|
7
|
Dere E, Pause BM, Pietrowsky R. Emotion and episodic memory in neuropsychiatric disorders. Behav Brain Res 2010; 215:162-71. [DOI: 10.1016/j.bbr.2010.03.017] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 03/05/2010] [Indexed: 11/25/2022]
|
8
|
Papathanassoglou EDE, Giannakopoulou M, Mpouzika M, Bozas E, Karabinis A. Potential effects of stress in critical illness through the role of stress neuropeptides. Nurs Crit Care 2010; 15:204-16. [DOI: 10.1111/j.1478-5153.2010.00363.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
9
|
Zoladz PR, Diamond DM. Linear and non-linear dose-response functions reveal a hormetic relationship between stress and learning. Dose Response 2008; 7:132-48. [PMID: 19543480 DOI: 10.2203/dose-response.08-015.zoladz] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Over a century of behavioral research has shown that stress can enhance or impair learning and memory. In the present review, we have explored the complex effects of stress on cognition and propose that they are characterized by linear and non-linear dose-response functions, which together reveal a hormetic relationship between stress and learning. We suggest that stress initially enhances hippocampal function, resulting from amygdala-induced excitation of hippocampal synaptic plasticity, as well as the excitatory effects of several neuromodulators, including corticosteroids, norepinephrine, corticotropin-releasing hormone, acetylcholine and dopamine. We propose that this rapid activation of the amygdala-hippocampus brain memory system results in a linear dose-response relation between emotional strength and memory formation. More prolonged stress, however, leads to an inhibition of hippocampal function, which can be attributed to compensatory cellular responses that protect hippocampal neurons from excitotoxicity. This inhibition of hippocampal functioning in response to prolonged stress is potentially relevant to the well-described curvilinear dose-response relationship between arousal and memory. Our emphasis on the temporal features of stress-brain interactions addresses how stress can activate, as well as impair, hippocampal functioning to produce a hormetic relationship between stress and learning.
Collapse
Affiliation(s)
- Phillip R Zoladz
- Medical Research Service, VA Hospital, and University of South Florida, Tampa, FL, 33620, USA
| | | |
Collapse
|
10
|
Psychophysiological Response to Severe Sport Injury Among Competitive Male Athletes: A Preliminary Investigation. JOURNAL OF CLINICAL SPORT PSYCHOLOGY 2007. [DOI: 10.1123/jcsp.1.1.68] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Features of posttraumatic distress have been associated with treatment noncompliance and delayed surgical recovery among general medical and trauma populations. Although cognitive-affective and behavioral features of posttraumatic distress have been demonstrated among adult and adolescent athletes with injuries, physiological responses associated with posttraumatic distress have not yet been examined in this population. The objective of this study was to examine psychophysiological stress reactivity to orthopedic trauma among male athletes who sustained a severe sport injury. Athletes with injuries (n= 7) and non-injured athlete controls (n= 5) completed self-report measures of psychological distress and were then shown injury video footage while heart rate and skin conductance measures were recorded. After exposure to orthopedic trauma-related video footage, athletes with injuries demonstrated significantly greater skin conductance reactivity and subjective distress compared to controls. As demonstrated among other medical and trauma populations, athletes with injuries exhibit exaggerated stress reactivity profiles when primed with orthopedic trauma stimuli.
Collapse
|
11
|
Diamond DM, Campbell AM, Park CR, Halonen J, Zoladz PR. The temporal dynamics model of emotional memory processing: a synthesis on the neurobiological basis of stress-induced amnesia, flashbulb and traumatic memories, and the Yerkes-Dodson law. Neural Plast 2007; 2007:60803. [PMID: 17641736 PMCID: PMC1906714 DOI: 10.1155/2007/60803] [Citation(s) in RCA: 380] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 12/18/2006] [Accepted: 12/20/2006] [Indexed: 12/29/2022] Open
Abstract
We have reviewed research on the effects of stress on LTP in the hippocampus, amygdala and prefrontal cortex (PFC) and present new findings which provide insight into how the attention and memory-related functions of these structures are influenced by strong emotionality. We have incorporated the stress-LTP findings into our "temporal dynamics" model, which provides a framework for understanding the neurobiological basis of flashbulb and traumatic memories, as well as stress-induced amnesia. An important feature of the model is the idea that endogenous mechanisms of plasticity in the hippocampus and amygdala are rapidly activated for a relatively short period of time by a strong emotional learning experience. Following this activational period, both structures undergo a state in which the induction of new plasticity is suppressed, which facilitates the memory consolidation process. We further propose that with the onset of strong emotionality, the hippocampus rapidly shifts from a "configural/cognitive map" mode to a "flashbulb memory" mode, which underlies the long-lasting, but fragmented, nature of traumatic memories. Finally, we have speculated on the significance of stress-LTP interactions in the context of the Yerkes-Dodson Law, a well-cited, but misunderstood, century-old principle which states that the relationship between arousal and behavioral performance can be linear or curvilinear, depending on the difficulty of the task.
Collapse
Affiliation(s)
- David M Diamond
- Medical Research Service, VA Hospital, Tampa, FL 33612, USA.
| | | | | | | | | |
Collapse
|
12
|
Franklin SO, Jimenez R. Increases in preproenkephalin mRNA levels in the Syrian hamster: The influence of glucocorticoids is dependent on age and tissue. Brain Res 2006; 1086:65-75. [PMID: 16597437 DOI: 10.1016/j.brainres.2006.02.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Revised: 02/19/2006] [Accepted: 02/21/2006] [Indexed: 12/22/2022]
Abstract
In adult hamsters, basal proenkephalin (Penk) gene expression in adrenals is independent of glucocorticoids and glucocorticoid receptor blockade, by RU 486, increases striatal preproenkephalin (PPenk) mRNA levels. However, glucocorticoids maintain both basal and induced Penk gene expression in rat adrenal (medulla) and striatum. This suggests species and tissue-specific differences in Penk gene regulation. Since studies show temporal coordination in Penk gene expression in developing hamster adrenal and striatum, we tested the hypothesis that increasing PPenk mRNA levels are dependent, while basal levels are independent of glucocorticoids in developing hamsters. To facilitate this study, we examined the influence of glucocorticoids on the temporal increases in developing hamster PPenk mRNA observed in adrenals between postnatal days 0 and 4 and in striatum between postnatal days 12 and 48. PPenk mRNA levels were determined in hamster pups after treatment with increasing doses of metyrapone (an 11beta hydroxylase inhibitor) or with the glucocorticoid receptor antagonist RU 486 +/- metyrapone between postnatal days 2 and 4. Levels were also determined 36 days after hypophysectomy at age 16-17 days. Although plasma glucocorticoid levels and/or the influence from glucocorticoids were reduced, only developmental increases in PPenk mRNA are influenced by glucocorticoids in hamster adrenals, while basal adrenal mRNA levels are unchanged. However, pituitary influence on striatal PPenk mRNA levels appears complex and may involve steroid and/or non-steroid factors. These results suggest that glucocorticoids regulate hamster Penk gene expression via a mechanism that varies with age and tissue and functions during the induction of the Penk gene and not to maintain basal gene expression. Possible mechanisms and species variation are discussed.
Collapse
Affiliation(s)
- Steven O Franklin
- Program in the Neuroscience of Drug Abuse, Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, 700 George Street, Durham, 27707, USA.
| | | |
Collapse
|
13
|
Diamond DM, Park CR, Campbell AM, Woodson JC. Competitive interactions between endogenous LTD and LTP in the hippocampus underlie the storage of emotional memories and stress-induced amnesia. Hippocampus 2005; 15:1006-25. [PMID: 16086429 DOI: 10.1002/hipo.20107] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This speculative review serves two purposes. First, it as an extension of the ideas we developed in a previous review (Diamond et al., Hippocampus, 2004;14:281-291), and second, it is a rebuttal to Abraham's (Hippocampus, 2004;14:675-676) critique of that review. We had speculated on the functional significance of the finding that post-training LTP induction produces retrograde amnesia. We noted the similarities between the findings that strong tetanizing stimulation can produce LTP and retrograde amnesia, and that a strong emotional experience can produce a long-lasting memory and retrograde amnesia, as well. The commonalities between LTP induction and emotional learning provided the basis of our hypothesis that an emotional experience generates endogenous LTD/depotentiation, which reverses synaptic plasticity formed during previous learning experiences, and endogenous LTP, which underlies the storage of new information. Abraham raised several concerns with our review, including the criticism that our speculation "falters because there is no evidence that stress causes LTD or depotentiation," and that research on stress and hippocampus has "failed to report any LTP-like changes." Abraham's points are well-taken because stress, in isolation, does not appear to generate long-lasting changes in baseline measures of hippocampal excitability. Here, within the context of a reply to Abraham's critique, we have provided a review of the literature on the influence of stress, novelty, fear conditioning, and the retrieval of emotional memories on cognitive and physiological measures of hippocampal functioning. An emphasis of this review is our hypothesis that endogenous forms of depotentiation, LTD and LTP are generated only when arousing experiences occur in conjunction with memory-related activation of the hippocampus and amygdala. We conclude with speculation that interactions among the different forms of endogenous plasticity underlie a form of competition by synapses and memories for access to retrieval resources.
Collapse
Affiliation(s)
- David M Diamond
- Department of Psychology, University of South Florida, Tampa, FL 33620, USA.
| | | | | | | |
Collapse
|
14
|
Diamond DM, Park CR, Woodson JC. Stress generates emotional memories and retrograde amnesia by inducing an endogenous form of hippocampal LTP. Hippocampus 2004; 14:281-91. [PMID: 15132427 DOI: 10.1002/hipo.10186] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Models of the neurobiology of memory have been based on the idea that information is stored as distributed patterns of altered synaptic weights in neuronal networks. Accordingly, studies have shown that post-training treatments that alter synaptic weights, such as the induction of long-term potentiation (LTP), can interfere with retrieval. In these studies, LTP induction has been relegated to the status of a methodological procedure that serves the sole purpose of disturbing synaptic activity in order to impair memory. This perspective has been expressed, for example, by Martin and Morris (2002: Hippocampus 12:609-636), who noted that post-training LTP impairs memory by adding "behaviorally meaningless" noise to hippocampal neural networks. However, if LTP truly is a memory storage mechanism, its induction should represent more than just a means with which to disrupt memory. Since LTP induction produces retrograde amnesia, the formation of a new memory should also produce retrograde amnesia. In the present report, we suggest that one type of learning experience, the storage of fear-related (i.e., stressful) memories, is consistent with this prediction. Studies have shown that stress produces potent effects on hippocampal physiology, generates long-lasting memories, and induces retrograde amnesia, all through mechanisms in common with LTP. Based on these findings, we have developed the hypothesis that a stressful experience generates an endogenous form of hippocampal LTP that substitutes a new memory representation for preexisting representations. In summary, our hypothesis implicates the induction of endogenous synaptic plasticity by stress in the formation of emotional memories and in retrograde amnesia.
Collapse
Affiliation(s)
- David M Diamond
- Department of Psychology, University of South Florida, 4202 E. Fowler Ave (PCD 4118G), Tampa, FL 33620, USA.
| | | | | |
Collapse
|
15
|
Zarrindast MR, Hadi M, Homayoun H, Postami P, Shafaghi B, Khavandgar S. The role of alpha-adrenoceptors in the amnestic effect of intracerebroventricular dexamethasone. Pharmacol Res 2002; 46:339-44. [PMID: 12361696 DOI: 10.1016/s1043661802001482] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Corticosteroids exert dual enhancing or impairing effects on cognitive functions. While their memory-enhancing effects have been well investigated, the mechanisms involved in their amnestic effects are not completely understood. Thus, we examined the role of alpha-adrenoceptors on dexamethasone-induced amnesia using step-through passive avoidance test in rat. Intracerebroventricular (i.c.v.) injection of dexamethasone (5 and 10 microg per rat) decreased the retention latencies. Likewise, intraperitoneal administration of alpha(2)-adrenoceptor agonist clonidine (0.1-0.3 mg kg(-1)) but not alpha(2)-adrenoceptor antagonist yohimbine (0.5-2 mg kg(-1)) decreased the retention latency. Yohimbine pre-treatment decreased the amnestic effects of dexamethasone or dexamethasone plus clonidine. On the other hand, intraperitoneal administration of alpha(1)-adrenoceptor agonist phenylephrine (0.5-2 mg kg(-1)) per se increased, while prazosin at 2 mg kg(-1) decreased the retention latency. Administration of phenylephrine before dexamethasone completely reversed the amnestic effect of the latter, while prozosin did not affect dexamethasone-induced amnesia. These data suggest that dexamethasone may induce its amnestic effect through activation of alpha(2)-adrenoceptors, leading to decreased alpha(1)-adrenergic activity.
Collapse
Affiliation(s)
- Mohammad Reza Zarrindast
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.
| | | | | | | | | | | |
Collapse
|
16
|
Abstract
Second impact syndrome (SIS) is a widely feared complication of traumatic brain injury. Although postulated to occur after repeated concussion, the evidence for such a premise is not compelling. This paper reviews the published evidence for and against the existence of this controversial entity. Rather than SIS being a complication of recurrent concussion, it is far more likely that the clinical condition represents "diffuse cerebral swelling," a well-recognized complication of traumatic brain injury. This condition is more common in children and adolescents, which reflects the known demographics of so-called "second impact syndrome." We propose that clinicians abandon the misleading term second impact syndrome and refer to the syndrome as diffuse cerebral swelling.
Collapse
Affiliation(s)
- P McCrory
- Centre for Sports Medicine Research & Education, and Brain Research Institute, University of Melbourne, Australia.
| |
Collapse
|
17
|
Joseph R. Frontal lobe psychopathology: mania, depression, confabulation, catatonia, perseveration, obsessive compulsions, and schizophrenia. Psychiatry 1999; 62:138-72. [PMID: 10420428 DOI: 10.1080/00332747.1999.11024862] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The frontal lobes can be subdivided into major functional neuroanatomical domains, which, when injured, surgically destroyed, or reduced in activity or volume, give rise to signature pathological and psychiatric symptomology. A review of case reports and over 50 years of research, including magnetic resonance imaging, positron emission tomography, and single photon emission computed tomography scans, indicates that apathy, "blunted" schizophrenia, major depression, and aphasic-perseverative disturbance of speech and thought are associated with left lateral as well as bilateral frontal (and striatal) abnormalities. Impulsiveness, confabulatory verbosity, grandiosity, increased sexuality, and mania are associated with right frontal (as well as bilateral) disturbances. Gegenhalten, catatonia, and disturbances of "will" are indicative of medial frontal injuries. Disinhibitory states and obsessive-compulsive perseverative abnormalities are more frequently observed with orbital frontal lobe dysfunction, including frontal-striatal disturbances. These associations, however, are not always clear-cut as patients with the same diagnosis may demonstrate different symptoms that may be due to an additional abnormality in a different region of the brain. Moreover, as the frontal subdivisions are richly interconnected, and as frontal lobe abnormalities are not always discrete or well localized, a wide array of seemingly divergent waxing and waning symptoms may be manifest, sometimes simultaneously, including manic depression and what has been referred to as the "frontal lobe personality."
Collapse
Affiliation(s)
- R Joseph
- Brain Research Laboratory, San Jose, CA 95126, USA
| |
Collapse
|