Unpleasant thoughts and anxiety induced by electrical cortical stimulation

Area of Science:

• Neuroscience
• Psychiatry
• Neurology

Background:

• Emotional processing is a key area of research interest.
• Understanding the neural basis of emotions is crucial for treating affective disorders.
• Intractable epilepsy provides a unique model for studying brain function through direct stimulation.

Purpose of the Study:

• To investigate the direct elicitation of emotional responses via electrical cortical stimulation in patients with intractable epilepsy.
• To identify specific cortical areas associated with different facets of negative emotional experiences.
• To explore the relationship between brain stimulation, emotional content, and associated somatic sensations.

Main Methods:

• Case study of three patients with intractable epilepsy undergoing surgical evaluation.
• Electrical cortical stimulation applied to specific brain regions, including the right anterior cingulate gyrus, right posterior cingulate gyrus, and right prefrontal cortex.
• Systematic recording and analysis of patient-reported emotional responses and subjective experiences.

Main Results:

• Electrical stimulation consistently elicited negative emotional responses across all three patients.
• Patient 1: Stimulation of the right anterior cingulate gyrus induced unpleasant thoughts.
• Patient 2: Stimulation of the right posterior cingulate gyrus evoked anxiety.
• Patient 3: Stimulation of the right prefrontal cortex resulted in anxiety accompanied by a somatic sensation.

Conclusions:

• Specific cortical regions are differentially involved in generating various aspects of emotional processing.
• Electrical cortical stimulation is a viable method for probing the neural substrates of emotion.
• The findings highlight the complex and regionally specific neural architecture underlying human emotional experience and its somatic correlates.