Most of us seem to have an underlying essence that makes us who we are – a constant that stays with us throughout our lives.

This essence has different names according to various spiritual or philosophical traditions. Buddhists call it the “self”, but reject the idea that we all have a single self that persists throughout our lives. Other monotheistic religions might call this essence a “soul” which survives our physical body and is judged based on our material deeds after death. Other philosophical traditions might refer to it as our “ego.”

While people have pondered these concepts for millennia, neuroscientists and psychologists are only just beginning to untangle many of the neurological and environmental mechanisms that combine to create this perception of integrated individuality.

In his new book be you, Anil Seth, neuroscientist and consciousness researcher at the University of Sussex, outlines five essential components that contribute to our conscious experience of individuality, each of which can be manipulated in studies to gain insight.

embodied self

Most people feel that at some point their body ends and the rest of the world begins. This sensation is known as the embodied self. But we can also (rather easily) trick our brain into believing that something inanimate is actually one of our appendages. Try the infamous rubber hand illusion and see for yourself.

The Perspective Self

the The perspective self allows us to experience the world from a first-person perspective. But there are also certain contexts where this perspective can be disturbed. There are even times when our point of view, or mind’s eye, can seem to operate outside of us.

An example of this change is known as depersonalization disorder – a condition in which people feel as if they are watching themselves go about their lives. People with this disorder often say they feel disconnected from reality and go through life on autopilot. Experiences of depersonalization usually coexist with traumatic events or prolonged severe stress.

Out-of-body experiences can also seem like a significant deviation from our typical sense of individuality. In these cases, a person can feel their first-person perspective hovering over their body. Some people describe these experiences as seeing themselves in the third person.

The Volitional Self

The volitional self, as Seth describes it, is related to feelings of agency and free will. Human beings, like any other organism, must interact with their environment in a way that ensures their continued survival. Although human beings cannot consciously control the internal states of their bodies (i.e. heartbeat, bowel movements, adrenaline levels), they can control the actions they take to ensure their survival. Theorists suggest this inherited ability can be inextricably linked to our feelings of agency.

But some clinical conditions are known to disrupt the intuition that we can dictate our own movements and decisions. people with schizophrenia, for example, may have difficulty recognizing their own actions. Additionally, people with alien hand syndrome feel that one or more of their members are foreigners and can move on their own.

The narrative self

The narrative self is associated with the autobiographical character of our memories. Scientists have observed that dementia and other neurodegenerative conditions can have significant effects on our narrative notions of individuality. As these diseases progress, memory and other cognitive functions may decline. Patients often forget careers, family members, and significant life events. In some cases, people even experience drastic personality changes.

The narrative self can also be altered quite dramatically when we experience what is called a flow state. People can enter a state of flux when they perform tasks so intensively practiced that their movements or thoughts become automatic. These activities include playing sports, using musical instruments, or even meditating.

The social self

Finally, social self relates to the roles we play in different social contexts and how we perceive others perceive us. As deeply social creatures, most people spend a lot of time considering other people’s opinions of us. We crave connection and validation among our peers. Some researchers might even argue that without the other people around us, we could not form a self-concept.

Overall, researchers do not fully understand the mechanisms behind these various aspects of individuality. Recent studies, however, have provided important insights. For example, neuroimaging has suggested that we use structures within the default mode network (which activates during rest and mental wandering) to process inner narratives and social interactions. As with previous work on the social self, some scientists argue that we must watch beyond the mind – looking at the whole body, as well as its environment, can be necessary to truly understand ourselves.