Anterior insula stimulation increases pain threshold in humans: a pilot study

Area of Science:

• Neuroscience
• Pain Management
• Neuromodulation

Background:

• Chronic pain presents a significant societal and financial burden.
• Opioid medications are standard treatments but carry risks of abuse and addiction.
• Novel non-pharmacological therapies are needed to address the opioid crisis and treat refractory pain.

Purpose of the Study:

• To investigate the effects of anterior insula stimulation on pain perception.
• To provide evidence for anterior insula stimulation as a potential therapeutic intervention for chronic pain.

Main Methods:

• Six patients with epilepsy undergoing intracranial electrode implantation participated.
• Direct anterior insula stimulation was performed while patients were awake.
• Quantitative sensory testing, laser-evoked potentials, and intracranial EEG were used to assess effects.
• Control and sham stimulations were included to ensure specificity and rule out placebo effects.

Main Results:

• Anterior insula stimulation significantly increased heat pain thresholds (p < 0.001).
• Stimulation intensity correlated with increased pain thresholds.
• Changes in intracranial EEG, reduced laser pain intensity, and attenuated laser-evoked potentials were observed.
• Effects persisted post-stimulation with no adverse events reported.

Conclusions:

• Anterior insula stimulation can safely modulate human cerebral pain processing.
• This approach represents a promising non-pharmacological strategy for chronic pain.
• Further research into the anterior insula as a neuromodulation target is warranted.