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Cognitive Impairments in Schizophrenia as Assessed Through Activation and Connectivity Measures of Magnetoencephalography (MEG) Data.

Hinkley LB, Owen JP, Fisher M, Findlay AM, Vinogradov S, Nagarajan SS - Front Hum Neurosci (2010)

Bottom Line: Although studies utilizing electroencephalography (EEG), PET and fMRI have contributed significantly to our understanding of these mechanisms, magnetoencephalography (MEG) possesses great potential to answer long-standing questions linking brain interactions to cognitive operations in the disorder.Finally, both bivariate and multivariate functional connectivity metrics of MEG data are useful for understanding how these interactions in the brain are impaired in schizophrenia, and how cognitive and clinical outcomes are affected as a result.We also present here data from our own laboratory that illustrates how some of these novel functional connectivity measures, specifically imaginary coherence (IC), are quite powerful in relating disconnectivity in the brain to characteristic behavioral findings in the disorder.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA.

ABSTRACT
The cognitive dysfunction present in patients with schizophrenia is thought to be driven in part by disorganized connections between higher-order cortical fields. Although studies utilizing electroencephalography (EEG), PET and fMRI have contributed significantly to our understanding of these mechanisms, magnetoencephalography (MEG) possesses great potential to answer long-standing questions linking brain interactions to cognitive operations in the disorder. Many experimental paradigms employed in EEG and fMRI are readily extendible to MEG and have expanded our understanding of the neurophysiological architecture present in schizophrenia. Source reconstruction techniques, such as adaptive spatial filtering, take advantage of the spatial localization abilities of MEG, allowing us to evaluate which specific structures contribute to atypical cognition in schizophrenia. Finally, both bivariate and multivariate functional connectivity metrics of MEG data are useful for understanding how these interactions in the brain are impaired in schizophrenia, and how cognitive and clinical outcomes are affected as a result. We also present here data from our own laboratory that illustrates how some of these novel functional connectivity measures, specifically imaginary coherence (IC), are quite powerful in relating disconnectivity in the brain to characteristic behavioral findings in the disorder.

No MeSH data available.


Related in: MedlinePlus

Relationship between evoked oscillatory activity (eOA) in response to speech sounds in patients with schizophrenia to auditory hallucination scores as measured through SAPS. During the period of 100–150 ms following a speech sound, the magnitude of the eOA was negatively correlated with auditory hallucinations in the left hemisphere only. No significant relationship was seen between eOA latency and SAPS scores in either the left or right hemispheres. Reproduced, with permission, from Hirano et al. (2008).
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Figure 4: Relationship between evoked oscillatory activity (eOA) in response to speech sounds in patients with schizophrenia to auditory hallucination scores as measured through SAPS. During the period of 100–150 ms following a speech sound, the magnitude of the eOA was negatively correlated with auditory hallucinations in the left hemisphere only. No significant relationship was seen between eOA latency and SAPS scores in either the left or right hemispheres. Reproduced, with permission, from Hirano et al. (2008).

Mentions: A number of other classical experimental designs in cognitive psychology have been adapted for use with MEG. For tasks such as mental arithmetic, MEG has been used to demonstrate both reductions in high-gamma sensor power (Kissler et al., 2000) and increases in delta and theta band activity (Fehr et al., 2003) in patients with schizophrenia. Disorganized brain activity (source clustering) recorded in MEG data during a categorical picture-naming task has also been shown to be present in patients with schizophrenia, and this impaired neural activity has been shown to be related to both positive and negative symptoms (Löw et al., 2006). In addition, examination of high-frequency cortical activity in MEG in response to speech stimuli has also been demonstrated to be related to clinical symptom scores. In patients with schizophrenia, the processing of speech sounds in the gamma (25–40 Hz) range over left auditory cortex is delayed, and negatively correlated with the severity of auditory hallucinations (Hirano et al., 2008; Figure 4).


Cognitive Impairments in Schizophrenia as Assessed Through Activation and Connectivity Measures of Magnetoencephalography (MEG) Data.

Hinkley LB, Owen JP, Fisher M, Findlay AM, Vinogradov S, Nagarajan SS - Front Hum Neurosci (2010)

Relationship between evoked oscillatory activity (eOA) in response to speech sounds in patients with schizophrenia to auditory hallucination scores as measured through SAPS. During the period of 100–150 ms following a speech sound, the magnitude of the eOA was negatively correlated with auditory hallucinations in the left hemisphere only. No significant relationship was seen between eOA latency and SAPS scores in either the left or right hemispheres. Reproduced, with permission, from Hirano et al. (2008).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2991173&req=5

Figure 4: Relationship between evoked oscillatory activity (eOA) in response to speech sounds in patients with schizophrenia to auditory hallucination scores as measured through SAPS. During the period of 100–150 ms following a speech sound, the magnitude of the eOA was negatively correlated with auditory hallucinations in the left hemisphere only. No significant relationship was seen between eOA latency and SAPS scores in either the left or right hemispheres. Reproduced, with permission, from Hirano et al. (2008).
Mentions: A number of other classical experimental designs in cognitive psychology have been adapted for use with MEG. For tasks such as mental arithmetic, MEG has been used to demonstrate both reductions in high-gamma sensor power (Kissler et al., 2000) and increases in delta and theta band activity (Fehr et al., 2003) in patients with schizophrenia. Disorganized brain activity (source clustering) recorded in MEG data during a categorical picture-naming task has also been shown to be present in patients with schizophrenia, and this impaired neural activity has been shown to be related to both positive and negative symptoms (Löw et al., 2006). In addition, examination of high-frequency cortical activity in MEG in response to speech stimuli has also been demonstrated to be related to clinical symptom scores. In patients with schizophrenia, the processing of speech sounds in the gamma (25–40 Hz) range over left auditory cortex is delayed, and negatively correlated with the severity of auditory hallucinations (Hirano et al., 2008; Figure 4).

Bottom Line: Although studies utilizing electroencephalography (EEG), PET and fMRI have contributed significantly to our understanding of these mechanisms, magnetoencephalography (MEG) possesses great potential to answer long-standing questions linking brain interactions to cognitive operations in the disorder.Finally, both bivariate and multivariate functional connectivity metrics of MEG data are useful for understanding how these interactions in the brain are impaired in schizophrenia, and how cognitive and clinical outcomes are affected as a result.We also present here data from our own laboratory that illustrates how some of these novel functional connectivity measures, specifically imaginary coherence (IC), are quite powerful in relating disconnectivity in the brain to characteristic behavioral findings in the disorder.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA.

ABSTRACT
The cognitive dysfunction present in patients with schizophrenia is thought to be driven in part by disorganized connections between higher-order cortical fields. Although studies utilizing electroencephalography (EEG), PET and fMRI have contributed significantly to our understanding of these mechanisms, magnetoencephalography (MEG) possesses great potential to answer long-standing questions linking brain interactions to cognitive operations in the disorder. Many experimental paradigms employed in EEG and fMRI are readily extendible to MEG and have expanded our understanding of the neurophysiological architecture present in schizophrenia. Source reconstruction techniques, such as adaptive spatial filtering, take advantage of the spatial localization abilities of MEG, allowing us to evaluate which specific structures contribute to atypical cognition in schizophrenia. Finally, both bivariate and multivariate functional connectivity metrics of MEG data are useful for understanding how these interactions in the brain are impaired in schizophrenia, and how cognitive and clinical outcomes are affected as a result. We also present here data from our own laboratory that illustrates how some of these novel functional connectivity measures, specifically imaginary coherence (IC), are quite powerful in relating disconnectivity in the brain to characteristic behavioral findings in the disorder.

No MeSH data available.


Related in: MedlinePlus