Overview

Holden’s research on near-death experience aftereffects emerged from a recognition that NDEs produce lasting changes extending far beyond the experience itself. These aftereffects span multiple dimensions of human functioning and require systematic measurement to understand their nature, prevalence, and impact. Holden has approached this challenge through instrument development, literature synthesis, and collaborative research with healthcare professionals and other NDE researchers.

The scope of NDE aftereffects encompasses biological changes, psychological transformations, spiritual development, and social relationship shifts.⁶ Holden has emphasized that these aftereffects manifest within a process of experience integration that can be manageable or deeply challenging, and may last from brief periods to many years. Understanding and measuring these aftereffects has become essential for healthcare providers, counselors, and the experiencers themselves.

Knowledge and attitudes measurement

Recognizing that healthcare professionals often lack adequate knowledge about NDEs and may hold negative attitudes toward experiencers, Holden collaborated with colleagues to develop the Knowledge and Attitudes About Near-Death Experiences Scale (KANDES).⁷ This 50-item instrument includes a 24-item attitude subscale and a 26-item knowledge subscale, with the knowledge component addressing NDE content, NDE aftereffects, and experiencer characteristics.

The KANDES demonstrated acceptable psychometric properties through exploratory factor analysis and reliability testing. Holden then applied this instrument in a large-scale study examining the impact of online education on counselors’ knowledge and attitudes. The results showed that 212 licensed professional counselors who completed a three-part NDE educational program showed significantly more accurate knowledge and more positive attitudes about NDEs compared to a control group of 112 counselors who completed unrelated online programs.¹ These findings supported the use of online training to improve counselors’ capacity to provide clinically and ethically sound treatment to near-death experiencers.

Scope of aftereffects

Holden’s comprehensive review of aftereffects literature identified that NDEs produce changes across biological, psychological, spiritual, and social domains.⁶ Psychological aftereffects include shifts in personality, values, and worldview. Spiritual aftereffects involve deepened religious or spiritual beliefs and practices. Social aftereffects manifest in relationship changes, including both deepened connections and significant strains.

One particularly significant social aftereffect involves marital relationships. In a retrospective study using Gottman’s Sound Marital House framework, Holden and Christian compared marriages of 26 NDErs before and after their experiences with marriages of 26 control participants before and after a self-identified life-changing event unrelated to NDEs. Results indicated significant reductions in marital meaning, adjustment, and stability in NDE couples, with 65% of NDE couples’ marriages ending in divorce compared to only 35% of control couples.⁵ These findings underscore the profound impact NDEs can have on intimate relationships and the importance of counseling support for NDErs and their spouses.

Electromagnetic and environmental effects

Among the more unusual reported aftereffects are electromagnetic phenomena. Holden and colleagues conducted quantitative research investigating whether NDErs experience greater electromagnetic effects than non-experiencers. In a retrospective study comparing 36 NDErs, 20 non-NDErs who reported a close brush with death, and 46 people who had not been close to death, researchers found a greater incidence of reported electromagnetic effects among NDErs than among participants in the other two groups.³ More electromagnetic effects were correlated with deeper NDEs, suggesting a dose-response relationship.

To bring conceptual clarity to this literature, Holden, Blalock, and Atwater conducted a comprehensive review proposing more precise terminology for electromagnetic and non-electromagnetic environmental effects following NDEs.⁸ They examined the distinction between effects involving electromagnetism and those that may co-occur with electromagnetic changes, relating these phenomena to the World Health Organization’s concepts of idiopathic environmental intolerance (IEI) and IEI-electromagnetic field attributed symptoms (IEI-EMF). This work established a framework for future research and clinical understanding of environmental effects in NDErs.

Spontaneous mediumship experiences

Holden identified and investigated a previously undocumented NDE aftereffect: spontaneous mediumship experiences (SMEs). In these experiences, NDErs report uninvited visits from deceased persons who request that the experiencer convey messages to living individuals.² This phenomenon differs from planned mediumship, in which a living person requests another to serve as a medium.

In an exploratory quantitative study of 89 participants recruited primarily through International Association for Near-Death Studies local groups, Holden, Foster, and Kinsey found that whereas 15% of participants reported at least one SME prior to their first or only NDE, 56% reported at least one following it. Participants reporting deeper NDEs were significantly more likely to report at least one post-NDE SME, with a medium effect size. Number of reported post-NDE SMEs ranged from 1 to over 20. Of those who reported degree of distress related to their SMEs, only 4% indicated very or extremely distressful experiences. Of participants who responded, 28% reported having sought help with their SMEs, 62% reported they had found at least one helpful coping strategy, and the most frequent source of helpful coping strategies was reportedly personal experience.²

Holden and Foster later engaged in scholarly debate regarding terminology for this phenomenon, defending the term “spontaneous mediumship” against alternative proposals, emphasizing that specificity in terminology is important for understanding the challenges many NDErs face when learning to set and maintain limits with the disembodied regarding both the timing of their appearance and the extent to which the NDEr is willing to accept the role of medium of communication.⁹

Veridical perception assessment

A central concern in NDE research involves the question of whether experiencers’ perceptions during out-of-body phases correspond to objective reality. Holden conducted pioneering research on this question, beginning with a hospital-based study examining visual perception during naturalistic near-death out-of-body experiences.¹⁰ Based on questionnaire responses from 63 subjects who had near-death out-of-body experiences, she found that at least some respondents described sufficiently complete and accurate visual perception during the experience to warrant pursuit of veridicality research in hospitals.

More recently, Holden collaborated with Greyson and international colleagues to develop the veridical Near-Death Experience Scale (vNDE Scale), a structured instrument for evaluating the evidential strength of perceptions reported during NDEs.⁴ Using a Delphi Method with 13 NDE experts, the team achieved consensus on eight criteria related to timing of investigation, medical and physical conditions, level of third-person verification, and the number, type, and quality of perceptions reported by the near-death experiencer, rated on a four-level Likert scale. Validation of the scale with 17 cases of potentially veridical NDEs by 11 independent human raters and three artificial raters based on Large-Language Models showed that in 14 of 17 cases (82.3%), overall agreement between human and artificial judges exceeded 75%, considering close levels of evidence strength.⁴

Holden has also engaged critically with skeptical arguments regarding veridical perception in NDEs. In response to claims that NDE perceptions may be hallucinatory or embellished, she presented a preliminary analysis of more than 100 cases of out-of-body NDEs, arguing that the evidence provides a more accurate view overall of the phenomenon of apparently nonphysical veridical perception during NDEs.¹¹

Related and similar experiences

As editor of the Journal of Near-Death Studies, Holden clarified the scope of experiences related to NDEs that fall within the purview of near-death studies research and publication. She identified three categories of “related and similar” experiences: those that can occur during NDEs and also outside the context of a close brush with death, including out-of-body experiences, telepathy, after-death communication, and past-life memory; experiences that occur under circumstances similar to those of NDEs; and experiences that share features with NDEs but occur under different circumstances.¹² This framework has helped establish coherent boundaries for the field while acknowledging the interconnected nature of transpersonal phenomena.

Field analysis and literature synthesis

Holden has contributed significantly to understanding the development and scope of near-death studies as a field. In collaboration with colleagues, she analyzed the scholarly periodical literature through 2001 and again through 2011, examining patterns related to publication dates and venues, experts and their most cited articles, and most and least published topics in the field.^{13, 14 These analyses revealed the growth and evolution of near-death studies as an interdisciplinary field, identifying underaddressed topics and tracking shifts in research focus over time.}