Systematic review maps emotion induction via SEEG stimulation

A systematic review published online 8 October 2026 in NeuroImage consolidates the evidence on emotional responses elicited by direct intracerebral electrical stimulation during stereoelectroencephalography (SEEG). Authored by Lucas Arrighi, Fabrice Bartolomei, and Francesca Pizzo, the review compiles how stimulation delivered through intracranial contacts has produced affective phenomena across limbic and paralimbic structures commonly sampled by depth electrodes.

What does the review cover?

The authors frame the work as a systematic review of emotion induction through intracerebral stimulation performed within SEEG protocols. SEEG, used in the presurgical evaluation of drug-resistant focal epilepsy, places multiple depth electrodes along oblique trajectories to sample suspected epileptogenic networks. The same electrodes routinely deliver single-pulse and brief-train stimulation to map eloquent cortex, delineate the seizure onset zone, and — increasingly — probe affective and cognitive functions.

By collating studies that report emotion-related responses to these stimulations, the review aims to clarify which anatomical targets, stimulation parameters, and patient populations most reliably produce such effects, and to expose the methodological inconsistencies that have hampered cross-centre comparison.

Why does emotion mapping matter in the SEEG suite?

In epilepsy monitoring units, electrical cortical stimulation is a well-established functional mapping tool. Mapping motor, language, and visual cortex protects eloquent regions during resection or laser ablation. Emotion, however, has historically received less structured attention in the operating room or the EMU read-out.

That asymmetry matters because limbic structures — the amygdala, hippocampus, insula, anterior cingulate, ventromedial prefrontal cortex, and orbitofrontal regions — fall within the SEEG sampling field whenever the suspected epileptogenic zone is mesial temporal or fronto-central. Stimulation at those contacts can produce transient emotional experiences, autonomic changes, orofacial movements, or visceral sensations that clinicians must interpret correctly.

Misreading these as seizure semiology, anxiety, or stimulation artifact can distort the surgical hypothesis. A consolidated evidence base helps neurophysiologists and epileptologists distinguish stimulation-induced affective responses from ictal phenomena — a distinction that directly influences resection margins and postoperative counselling.

How will the data change reading-room practice?

For the clinical neurophysiologist reviewing stimulation trials, a systematic catalogue of emotion-eliciting sites translates into a more reliable differential. If the review confirms that low-current stimulation of the amygdala, for example, consistently produces fear or autonomic arousal across multiple cohorts, readers gain a Bayesian anchor for interpreting similar events in their own patients. The same logic applies to insular and cingulate stimulation, where reported responses span visceral, autonomic, and mood-related domains.

For the epilepsy surgery conference, the data may sharpen how teams report "positive" or "negative" emotional responses during functional mapping. Standardised reporting — stimulation frequency, pulse width, current intensity, contact location in MNI or Talairach space, response latency, and subjective report — would let centres compare findings rather than rely on anecdotal case descriptions.

Why SEEG and not another modality?

The review concerns intracranial recording exclusively. Scalp EEG, MEG, and fMRI cannot reproduce the focal, depth-targeted stimulation that SEEG enables. The technique differs from electrocorticography (ECoG) with subdural grids primarily in spatial sampling: depth electrodes reach medial temporal, insular, and cingulate targets that grids cover poorly or not at all. That anatomical reach is precisely what makes SEEG the dominant platform for limbic stimulation studies.

No animal-model data are involved. The review synthesises human intracranial recordings from patients undergoing epilepsy surgery evaluation, and the authors distinguish any investigational neuroscience claims from the clinical mapping context in which the data arose.

What comes next?

The publication lands as several groups extend SEEG-based stimulation work beyond mapping, into affective and cognitive neuroscience, and into closed-loop or brain-computer-interface paradigms. A shared, systematically assembled atlas of emotion-eliciting sites would accelerate that work and standardise reporting across centres.

Arrighi, Bartolomei, and Pizzo's review provides that map. The next step — anticipated by clinical neurophysiologists — is whether the field adopts the proposed synthesis as a reference for both research protocols and presurgical consent discussions in patients whose SEEG trajectories are expected to sample limbic cortex.