The Watts Connectedness Scale: a new scale for measuring a sense of connectedness to self, others, and world

This paper (2022) uses data from online surveys (n=1,226) and a trial comparing psilocybin to escitalopram (n=52) to validate and test a newly developed scale which measures the effects psychedelics have on feelings of connectedness; the Watts Connected Scale (WCS). The WCS measures connectedness across the three domains of connectedness to self, others, and the world. Factor analysis of all WCS items revealed three main factors with good internal consistency, and the WCS showed good construct validity. Acute measures of ‘mystical experience’, ‘emotional breakthrough’, and ‘communitas’ correlated positively with post-psychedelic changes in connectedness.


Rationale A general feeling of disconnection has been associated with mental and emotional suffering. Improvements to a sense of connectedness to self, others and the wider world have been reported by participants in clinical trials of psychedelic therapy. Such accounts have led us to a definition of the psychological construct of ‘connectedness’ as ‘a state of feeling connected to self, others and the wider world’. Existing tools for measuring connectedness have focused on particular aspects of connectedness, such as ‘social connectedness’ or ‘nature connectedness’, which we hypothesise to be different expressions of a common factor of connectedness. Here, we sought to develop a new scale to measure connectedness as a construct with these multiple domains. We hypothesised that (1) our scale would measure three separable subscale factors pertaining to a felt connection to ‘self’, ‘others’ and ‘world’ and (2) improvements in total and subscale WCS scores would correlate with improved mental health outcomes post psychedelic use.

Objectives To validate and test the ‘Watts Connectedness Scale’ (WCS).

Methods Psychometric validation of the WCS was carried out using data from three independent studies. Firstly, we pooled data from two prospective observational online survey studies. The WCS was completed before and after a planned psychedelic experience. The total sample of completers from the online surveys was N=1226. Exploratory and confirmatory factor analysis were performed, and construct and criterion validity were tested. A third dataset was derived from a double-blind randomised controlled trial (RCT) comparing psilocybin-assisted therapy (n=27) with 6 weeks of daily escitalopram (n=25) for major depressive disorder (MDD), where the WCS was completed at baseline and at a 6-week primary endpoint.

Results As hypothesised, factor analysis of all WCS items revealed three main factors with good internal consistency. WCS showed good construct validity. Significant post-psychedelic increases were observed for total connectedness scores (η2=0.339, p<0.0001), as well as on each of its subscales (p<0.0001). Acute measures of ‘mystical experience’, ‘emotional breakthrough’, and ‘communitas’ correlated positively with post-psychedelic changes in connectedness (r=0.42, r=0.38, r=0.42, respectively, p<0.0001). In the RCT, psilocybin therapy was associated with greater increases in WCS scores compared with the escitalopram arm (ηp2=0.133, p=0.009).

Conclusions The WCS is a new 3-dimensional index of felt connectedness that may sensitively measure therapeutically relevant psychological changes post-psychedelic use. We believe that the operational definition of connectedness captured by the WCS may have broad relevance in mental health research.”

Authors: Rosalind Watts, Hannes Kettner, Dana Geerts, Sam Gandy, Laura Kartner, Lea Mertens, Christopher Timmerman, Matthew M. Nour, Mendel Kaelen, David Nutt, Robin Carhart-Harris & Leor Roseman


One of the papers leading authors, Leor Roseman, dives into some of the paper highlights in this Twitter thread.

Summary of The Watts Connectedness Scale: a new scale for measuring a sense of connectedness to self, others, and world


Psychedelic therapy participants often report feeling connected to their senses, bodies, emotions, friends, family, nature, the living world, global humanity, purpose and meaning.

Many studies have argued that a sense of felt connection to self, other people and the world around us has a profound effect on our individual and collective wellbeing. We hypothesize that different types of connectedness may be linked by a common general factor.

The experience of feeling connected to self and others, and the interconnected living world, is commonly described by psychedelic ‘users’, whether they use be in ceremonial, festival, dance party or therapeutic contexts.

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Study details

Topics studied

Study characteristics

1278 Humans


Authors associated with this publication with profiles on Blossom

Rosalind Watts
Rosalind Watts is a clinical psychologist and clinical lead at the Psychedelics Research Group at Imperial College London. She is also known for developing the 'Accept, Connect, Embody' psychedelic therapy model.

David Nutt
David John Nutt is a great advocate for looking at drugs and their harm objectively and scientifically. This got him dismissed as ACMD (Advisory Council on the Misuse of Drugs) chairman.

Robin Carhart-Harris
Dr. Robin Carhart-Harris is the Founding Director of the Neuroscape Psychedelics Division at UCSF. Previously he led the Psychedelic group at Imperial College London.

Chris Timmermann
Chris Timmerman is a postdoc at Imperial College London. His research is mostly focussed on DMT.

Mendel Kaelen
Mendel Kaelen is a neuroscientist and entrepreneur, researching and developing a new category of psychotherapeutic tools for care-seekers and care-providers. Mendel has researched the incomparable effects of music on the brain during LSD-assisted psychotherapy. His work has determined how LSD increases enhanced eyes-closed visual imagery, including imagery of an autobiographical nature. This gives light to how music can be used as another dimension in helping psychotherapists create the ideal setting for their patients.

Leor Roseman
Leor Roseman is a researcher at the Centre for Psychedelic Research, Imperial College London. His work focussed on psilocybin for depression, but is now related to peace-building through psychedelics.

Sam Gandy
Sam Gandy has been working on psychedelics at Imperial College London and the Beckley Foundation, here he studies how psychedelics reconnect us to nature.


Institutes associated with this publication

Imperial College London
The Centre for Psychedelic Research studies the action (in the brain) and clinical use of psychedelics, with a focus on depression.

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