#2 Saeedeh Sadeghi & Irena Arslanova: Heart and time perception

This episode, I talk to Saeedeh Sadeghi (Cornell University) and Irena Arslanova (Royal Holloway - London) about the heart and time perception. If you have ever been in a car accident, you might have felt as if time was slowing down. Some previous studies have tried to explain this phenomenon and argued that a state of 'arousal' may slow down time (subjectively). It's a bit more complicated than that. This year, Saeedeh and Irena published two papers showing how not average heart rate but heart dynamics on the sub-second scale influence time perception. Within a single cardiac cycle, time may contract and expand. We go in-depth on the methodology and findings of their papers and make links to interoception, predictive coding, meditation, breathing, psychoactive substances, and the many time perception theories out there. At the end, we also talk about science communication and their future research plans.

Full show notes (with extra figures):

https://akseliilmanen.wixsite.com/home/post/pod02

Timestamps:

(00:00:00) - Saeedeh's and Irena's background

(00:05:09) - Does 'arousal' slow down time?

(00:12:20) - Virtual Reality subway study

(00:15:58) - Orienting response in evolution and pregnancy

(00:20:57) - Phenomenology of orienting response vs meditation

(00:27:52) - Temporal bisection task & methodology

(00:35:55) - Heart anatomy, systole and diastole explained

(00:40:34) - Subjective time contracts and expands within each heartbeat

(00:53:28) - How sub-second heart dynamics interact with average heart rate

(01:02:43) - Oscillations & striatal beat frequency model

(01:08:24) - Individual differences in interoception and heart-rate variability

(01:12:16) - Heart-brain communication & the insula as an integrator

(01:26:32) - Question by Josh Goheen on how breathing modulates the heart

(01:32:19) - Psychoactive substances and slowing of breath

(01:37:11) - Neural time perception theories (Roseboom, Tsao, Buonomano)

(01:46:41) - Time tracking in retrospective and prospective memory

(01:50:53) - Science communication with the public & future directions

(01:59:53) - Outro

Saeedeh Sadeghi

• Twitter: @SdSadeghi1
• Website
• Wrinkles in subsecond time perception are synchronized to the heart (2023)
• Affective experience in a virtual crowd regulates perceived travel time (2022)

Irena Arslanova

• Twitter: @irena_arslanova
• Website
• Perceived time expands and contracts within each heartbeat (2023)
• Seeing Through Each Other’s Hearts: Inferring Others’ Heart Rate as a Function of Own Heart Rate Perception and Perceived Social Intelligence (2022)

Josh Goheen

• LinkedIn
• From Lung to Brain: Respiration Modulates Neural and Mental Activity (2023)

My BSc dissertation: Graph-driven comparative phenomenology of altered time perception in over 20,000 trip reports URL

Other books/papers mentioned:

Marc Wittmann (2017): Felt Time: The Science of How We Experience Time book

Claudia Hammond (2013): Time Warped: Unlocking the Mysteries of Time Perception book

Craig, 2009: Emotional moments across time: a possible neural basis for time perception in the anterior insulas paper

Sarigiannidis et al., 2020: Anxiety makes time pass quicker while fear has no effect paper

Corcoran et al., 2023: Visceral afferent training in action paper

Review paper on striatal beat frequency model (2016)

Friston, 2018: Am I Self-Conscious? (Or Does Self-Organization Entail Self-Consciousness?)