Self-induced intracerebral gamma oscillations in the human cortex

Area of Science:

• Neuroscience
• Cognitive Science
• Neurology

Background:

• Gamma oscillations (30-80 Hz) are vital for cognitive functions and coordinated neural activity.
• Abnormalities in gamma oscillations are linked to various neurological and psychiatric diseases.
• Previous studies showed animals can modulate gamma power via operant conditioning.

Purpose of the Study:

• To investigate if humans can voluntarily modulate intracerebral gamma oscillations using a closed-loop system.
• To explore the effects of gamma modulation on other brain regions and frequency couplings.
• To assess the spatial specificity of gamma upregulation, particularly with microelectrode targets.

Main Methods:

• Utilized a closed-loop experimental setup with intracerebral recordings in six epileptic patients.
• Patients underwent training to increase gamma power (30-80 Hz) at fronto-temporal cortical sites.
• Microelectrode recordings were used in two subjects to examine gamma activity at micro-domain levels.

Main Results:

• Intracerebral gamma power was successfully increased in the gamma frequency range in human subjects.
• Gamma training led to increased gamma power in other cortical areas and enhanced gamma-slow oscillation coupling (3-12 Hz).
• Upregulation of gamma activity was achieved with high spatial specificity in micro-domains using microelectrodes, without spreading to macroelectrodes.

Conclusions:

• Intracerebral gamma modulation is achievable rapidly and voluntarily in humans, extending beyond the motor system.
• The findings highlight the potential for precise, high-resolution therapeutic interventions targeting gamma oscillations.
• This research paves the way for novel clinical applications in treating neurological conditions associated with gamma dysregulation.