Secondary consciousness is an individual’s accessibility to their history and plans. The ability allows its possessors to go beyond the limits of the remembered present of primary consciousness.

Primary consciousness can be defined as simple awareness that includes perception and emotion. As such, it is ascribed to most animals.

By contrast, secondary consciousness depends on and includes such features as self-reflective awareness, abstract thinking, volition, and metacognition. The term was coined by Gerald Edelman.

Brief history and overview

Since Descartes‘s proposal of dualism, it became a general consensus that the mind had become a matter of philosophy and that science was not able to penetrate the issue of consciousness- that consciousness was outside of space and time.

However, over the last 20 years, many scholars have begun to move toward a science of consciousness. Such notable neuroscientists that have led the move to neural correlates of the self and of consciousness are Antonio Damasio and Gerald Edelman.

Damasio has demonstrated that emotions and their biological foundation play a critical role in high-level cognition, and Edelman has created a framework for analyzing consciousness through a scientific outlook.

The current problem consciousness researchers face involves explaining how and why consciousness arises from neural computation. In his research on this problem, Edelman has developed a theory of consciousness, in which he has coined the terms primary consciousness and secondary consciousness.

Despite being an often criticized theory, Edelman’s theory of consciousness is regarded as the most neurobiologically sound and accurate description of consciousness to date.

The author puts forward the belief that consciousness is a particular kind of brain process; linked and integrated, yet complex and differentiated.

Evolution towards secondary consciousness

Edelman argues that the evolutionary emergence of consciousness depended on the natural selection of neural systems that gave rise to consciousness, but not on selection for consciousness itself.

He is noted for his theory of neuronal group selection, also known as Neural Darwinism, which displays the belief that consciousness is the product of natural selection.

He believes consciousness is not something separate from the real world, thus the attempt to eliminate Descartes’ “dualism” as a possible consideration. He also rejects theories based on the notion that the brain is a computer or an instructional system.

Instead, he suggests that the brain is a selectional system, one in which large numbers of variant circuits are generated epigenetically.

He claims the potential connectivity in the neural net “far exceeds the number of elementary particles in the universe“.

Exhibiting secondary consciousness in the animal kingdom

While animals with primary consciousness have long-term memory, they lack explicit narrative, and, at best, can only deal with the immediate scene in the remembered present.

While they still have an advantage over animals lacking such ability, evolution has brought forth a growing complexity in consciousness, particularly in mammals.

Animals with this complexity are said to have secondary consciousness. Secondary consciousness is seen in animals with semantic capabilities, such as the four great apes. It is present in its richest form in the human species, which is unique in possessing complex language made up of syntax and semantics.

In considering how the neural mechanisms underlying primary consciousness arose and were maintained during evolution, it is proposed that at some time around the divergence of reptiles into mammals and then into birds, the embryological development of large numbers of new reciprocal connections allowed rich re-entrant activity to take place between the more posterior brain systems carrying out perceptual categorization and the more frontally located systems responsible for value-category memory.

The ability of an animal to relate a present complex scene to its own previous history of learning conferred an adaptive evolutionary advantage.

At much later evolutionary epochs, further re-entrant circuits appeared that linked semantic and linguistic performance to categorical and conceptual memory systems. This development enabled the emergence of secondary consciousness.


For the advocates of the idea of secondary consciousness, self-recognition serves as a critical component and a key defining measure. What is most interesting then, is the evolutionary appeal that arises with the concept of self-recognition.

In non-human species and in children, the “mirror test” has been used as an indicator of self-awareness. In these experiments, subjects are placed in front of a mirror and provided with a mark that cannot be seen directly but is visible in the mirror.

Research on animal consciousness

Many researchers of consciousness have looked upon such types of research in animals as significant and interesting approaches.

Ursula Voss of the Universität Bonn believes that the theory of protoconsciousness may serve as an adequate explanation for self-recognition found in this bird species, as they would develop secondary consciousness during REM sleep. She added that many types of birds have very sophisticated language systems.

Don Kuiken of the University of Alberta finds such research interesting as well as if we continue to study consciousness with animal models (with differing types of consciousness), we would be able to separate the different forms of reflectiveness found in today’s world.

Lucid vs. non-lucid dreaming as a model

In the last couple of decades, dream research has begun to focus on the field of consciousness. Through lucid dreaming, NREM sleep, REM sleep, and waking states, many dream researchers are attempting to scientifically explore consciousness.

When exploring consciousness through the concept of dreams, many researchers believe the general characteristics that constitute primary and secondary consciousness remain intact:

“Primary consciousness is a state in which you have no future or past, a state of just being…. no executive ego control in your dreams, no planning, things just happen to you, you just are in a dream. Yet, everything feels real…The secondary is based on language, has to do with self-reflection, it has to do with forming abstractions, and that is dependent on language. Only animals with language have secondary consciousness”.

Prefrontal cortex

Some notable, albeit criticized findings include the functions of the prefrontal cortex that are most relevant to the self-conscious awareness that is lost in sleep, commonly termed as ‘executive’ functions.

These include self-observation, planning, prioritizing and decision-making abilities, which are, in turn, based upon more basic cognitive abilities such as attention, working memory, temporal memory, and behavioral inhibition.

Some experimental data which display differences between the self-awareness experienced in waking and its diminution in dreaming can be explained by deactivation of the dorsolateral prefrontal cortex during REM sleep.

It has been proposed that deactivation results from direct inhibition of the dorsolateral prefrontal cortical neurons by acetylcholine, the release of which is enhanced during REM sleep.


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