CSF Levels of γ-Aminobutyric Acid in Schizophrenia

Schizophrenia: Some Current Neurochemical Approaches

“…Only mean values are quoted in this paper, but the standard deviations suggested a wide spread of values that may eventually provide evidence for heterogeneity. The results of McCarthy et al were not confirmed by the latest paper on this subject (Van Kammen et al, 1982). These authors reported a tendency for CSF GABA levels to be low in young patients during the early stages of their illness, but with increasing length of hospitalization the levels tended to increase.…”

Schizophrenia: Some Current Neurochemical Approaches

“…Only mean values are quoted in this paper, but the standard deviations suggested a wide spread of values that may eventually provide evidence for heterogeneity. The results of McCarthy et al were not confirmed by the latest paper on this subject (Van Kammen et al, 1982). These authors reported a tendency for CSF GABA levels to be low in young patients during the early stages of their illness, but with increasing length of hospitalization the levels tended to increase.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…For example, pharmacological fMRI has been used to generate empirical models of E/I balance based on functional connectivity 70,71 . Furthermore, cerebrospinal fluid GABA levels have been used as a proxy measure for E/I balance alterations in patients with schizophrenia [72][73][74] . However, these methods are relatively intrusive, expensive, and/or require specialized infrastructure.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…In this study, a subanesthetic reduced the PSD exponent, supporting the hypothesis that ketamine's disinhibitory effects are associated with a shift in EEG spectral power from lower to higher frequencies 67 . Preclinical studies have shown that ketamine increases E/I balance in the medial prefrontal cortex (mPFC) by reducing interneuron activity, as demonstrated using electrophysiology 68-70 , microdialysis 71 , and other approaches 72 . However, intracortical recordings in nonhuman primates have shown that ketamine's effects vary across neuronal populations and cortical layers 73 .…”

Schizophrenia: Some Current Neurochemical Approaches

“…Only mean values are quoted in this paper, but the standard deviations suggested a wide spread of values that may eventually provide evidence for heterogeneity. The results of McCarthy et al were not confirmed by the latest paper on this subject (Van Kammen et al, 1982). These authors reported a tendency for CSF GABA levels to be low in young patients during the early stages of their illness, but with increasing length of hospitalization the levels tended to increase.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…For example, pharmacological fMRI has been used to generate empirical models of E/I balance based on functional connectivity 70,71 . Furthermore, cerebrospinal fluid GABA levels have been used as a proxy measure for E/I balance alterations in patients with schizophrenia [72][73][74] . However, these methods are relatively intrusive, expensive, and/or require specialized infrastructure.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…In this study, a subanesthetic reduced the PSD exponent, supporting the hypothesis that ketamine's disinhibitory effects are associated with a shift in EEG spectral power from lower to higher frequencies 67 . Preclinical studies have shown that ketamine increases E/I balance in the medial prefrontal cortex (mPFC) by reducing interneuron activity, as demonstrated using electrophysiology 68-70 , microdialysis 71 , and other approaches 72 . However, intracortical recordings in nonhuman primates have shown that ketamine's effects vary across neuronal populations and cortical layers 73 .…”

Schizophrenia: Some Current Neurochemical Approaches

“…Only mean values are quoted in this paper, but the standard deviations suggested a wide spread of values that may eventually provide evidence for heterogeneity. The results of McCarthy et al were not confirmed by the latest paper on this subject (Van Kammen et al, 1982). These authors reported a tendency for CSF GABA levels to be low in young patients during the early stages of their illness, but with increasing length of hospitalization the levels tended to increase.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…For example, pharmacological fMRI has been used to generate empirical models of E/I balance based on functional connectivity 70,71 . Furthermore, cerebrospinal fluid GABA levels have been used as a proxy measure for E/I balance alterations in patients with schizophrenia [72][73][74] . However, these methods are relatively intrusive, expensive, and/or require specialized infrastructure.…”

Opposing Modulation of EEG Aperiodic Component by Ketamine and Thiopental: Implications for the Noninvasive Assessment of Cortical E/I Balance in Humans

“…In this study, a subanesthetic reduced the PSD exponent, supporting the hypothesis that ketamine's disinhibitory effects are associated with a shift in EEG spectral power from lower to higher frequencies 67 . Preclinical studies have shown that ketamine increases E/I balance in the medial prefrontal cortex (mPFC) by reducing interneuron activity, as demonstrated using electrophysiology 68-70 , microdialysis 71 , and other approaches 72 . However, intracortical recordings in nonhuman primates have shown that ketamine's effects vary across neuronal populations and cortical layers 73 .…”