Hallucinations in Parkinson’s disease (PD) are one of the most common non-motor symptoms, affecting about half of all patients, and the most common form are presence hallucinations (PH). Some individuals with PD report sensing the presence of deceased loved ones, referred to as grief or bereavement hallucinations. In these experiences, people report feeling the presence, hearing, seeing, or otherwise perceiving a deceased person. We refer to them as “after death experiences” (ADEs). We analyzed the phenomenology of ADEs in six patients with PD. Relying on in-depth interviews, we describe the appearance and evolution of ADEs, their emotional aspects, how ADEs manifest, and how patients accounted for the experience. We report several similarities between ADEs in patients with PD and those in bereaved individuals (not related to PD), but also important differences. Patients with PD experience repeated ADEs. This reoccurrence allowed us to examine the way in which people make sense of these experiences by using both cognitive and reflective language. Our findings are not only of relevance for ADEs in PD, but also for a better understanding of ADEs in other contexts, allowing to form new hypotheses about ADEs and their social-cognitive mechanisms to inspire future behavioral and neurocognitive research.

O.B. is inventor on patent US 10,286,555 B2 (Title: Robot-controlled induction of the feeling of a presence) held by the Swiss Federal Institute (EPFL) that covers the robot-controlled induction of presence hallucinations. O.B. is inventor on patent US 10,349,899 B2 (Title: System and method for predicting hallucinations) held by the Swiss Federal Institute (EPFL) that covers a robotic system for the prediction of hallucinations for diagnostic and therapeutic purposes. O.B. is cofounder and shareholder of Metaphysiks Engineering SA. O.B. is a member of the board and shareholder of Mindmaze SA.

This research was supported by the Swiss National Science Foundation [grant n. 188798], CARIGEST SA (Fondazione Teofilo Rossi di Montelera e di Premuda and a second one wishing to remain anonymous) and Parkinson Suisse to O.B.; the Swiss National Science Foundation [grant n. 221182] and the Leenaards Foundation to F.B.; the Synapsis Foundation to O.B and F.B.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Geneva Cantonal Commission of Ethics in Research (CCER) of Geneva, Switzerland gave ethical approval for this work (Ethics protocol nnumber 2019-02275).

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The data that support the findings of this study are available from the corresponding author, C.A., upon reasonable request.