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Amplitude of low-frequency oscillations in schizophrenia: A resting state fMRI study

Division of Clinical Research, Nathan Kline Institute, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA.
Schizophrenia Research (Impact Factor: 3.92). 10/2009; 117(1):13-20. DOI: 10.1016/j.schres.2009.09.030
Source: PubMed

ABSTRACT

Recently, a great deal of interest has arisen in resting state fMRI as a measure of tonic brain function in clinical populations. Most studies have focused on the examination of temporal correlation between resting state fMRI low-frequency oscillations (LFOs). Studies on the amplitudes of these low-frequency oscillations are rarely reported. Here, we used amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF; the relative amplitude that resides in the low frequencies) to examine the amplitude of LFO in schizophrenia. Twenty-six healthy controls and 29 patients with schizophrenia or schizoaffective disorder participated. Our findings show that patients showed reduced low-frequency amplitude in proportion to the total frequency band investigated (i.e., fALFF) in the lingual gyrus, left cuneus, left insula/superior temporal gyrus, and right caudate and increased fALFF in the medial prefrontal cortex and the right parahippocampal gyrus. ALFF was reduced in patients in the lingual gyrus, cuneus, and precuneus and increased in the left parahippocampal gyrus. These results suggest LFO abnormalities in schizophrenia. The implication of these abnormalities for schizophrenic symptomatology is further discussed.

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    • "Hz) in a wide range of brain regions, such as the basal ganglia, thalamus, and precuneus, suggesting that the pattern of intrinsic brain activity is sensitive to specific frequency bands. Furthermore, it has been shown that patients with cognitive disorders exhibit frequencydependent changes in abnormal LFO amplitudes (Hoptman et al., 2010;Han et al., 2012). Several other studies (Salvador et al., 2008;Baliki et al., 2011;Wee et al., 2012) also investigated the effects of different frequency bands on the global properties of wholebrain functional networks and brain states. "
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    • "Network (CEN) is reduced in schizophrenia (Karbasforoushan et al, 2012;Hoptman et al, 2010). "
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    ABSTRACT: Over the past 20 years, the advent of advanced techniques has significantly enhanced our knowledge on the brain. Yet, our understanding of the physiological and pathological functioning of the mind is still far from being exhaustive. Both the localizationist and the reductionist neuroscientific approaches to psychiatric disorders have proven to be largely unsatisfactory and are outdated. Accruing evidence suggests that psychoanalysis can engage the neurosciences in a productive and mutually enriching dialogue that may further our understanding of psychiatric disorders. In particular, advances in brain connectivity research have provided evidence supporting the convergence of neuroscientific findings and psychoanalysis and helped characterize the circuitry and mechanisms that underlie higher brain functions. In the present paper we discuss how knowledge on brain connectivity can impact neuropsychoanalysis, with a particular focus on schizophrenia. Brain connectivity studies in schizophrenic patients indicate complex alterations in brain functioning and circuitry, with particular emphasis on the role of cortical midline structures and the default mode network. These networks seem to represent neural correlates of psychodynamic concepts central to the understanding of schizophrenia and of core psychopathological alterations of this disorder (i.e. ego disturbances and impaired primary process thinking).
    Full-text · Article · Jan 2016 · Frontiers in Human Neuroscience
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    • "ALFF has been widely used to investigate abnormal brain fluctuations and regional spontaneous activity in different neuropsychiatric disorders. More detailed information and examples can be found in previous studies (Hoptman et al., 2010; Liu et al., 2012; Zou et al., 2008). "
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    ABSTRACT: Functional neuroimaging techniques provide important insight into the pathophysiology of neurodegenerative disorders such as Parkinson's disease (PD) in-vivo. Recently, resting-state functional magnetic resonance imaging (rs-fMRI) has been applied as a non-invasive tool in many studies to assess functional abnormalities observed in PD without the effects of particular motor or cognitive tasks. In this review, we summarized 50 original PD rs-fMRI studies and subdivided them based on the medication status of the patients to highlight the impact of dopamine replacement therapy (DRT) when rs-fMRI was used to assess patients with PD. Although there are many different published approaches to analyzing rs-fMRI in PD, it seems that DRT plays a critical role in the functional reorganization of the brain throughout all of these approaches. In particular, studies that compared PD patients with and without medication demonstrated that DRT normalizes aberrant functional patterns in PD and leads to an improvement of PD symptoms. Thus, researchers should consider DRT as a confounding factor, which could result in misinterpretations. We suggest that performing rs-fMRI in de novo patients could be a method of choice to study the fundamental functional abnormalities in PD independent of the effects of DRT. However, it is necessary to carefully control for excessive involuntary head motions in the patients not receiving DRT. On the other hand, recruiting patients under daily DRT might be favorable to assess particular interventions in clinical routine.
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