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What is Consciousness?

Author: Alina Yang

Editors: Justin Tai, Linzi Yeung

Artist: Helen Gong


The heart is the human seat of thought. The Ancient Egyptians revered the heart as one of the eight parts of the human body, holding it in high regard as a source of intelligence and wisdom. As demonstrated in the sacred mummification process, the heart was meticulously preserved to guarantee its availability during judgment in the afterlife. This was done in contrast to other organs, like the brain, which were removed and disposed of. Until the 19th century, the notion that consciousness could arise from physical processes in the brain was considered “blasphemy” or “madness” and was dismissed by many. Even today, psychologists continue to struggle with the true definition of consciousness, with various questions being raised: What is narrating our inner thoughts? Why is it that you can recognize yourself in the mirror, but your cat can’t? Where do we all go when we sleep, and why can a simple dream make us question our reality? 

Consciousness is considered the most intimate experience we have – and possibly the least understood. Psychologists define consciousness as our awareness of ourselves and our environment. Consciousness can also be interpreted as a lightbulb observing the way it can flicker and split. In either interpretation, psychology is the tool we use to assist in our understanding of consciousness, clarifying it through the identification of discrete modes of awareness, which are subject to change based on our mental activity, brain chemistry, and environment. 

The states of consciousness are identified and studied using various tools, most notably the electroencephalogram, or EEG. EEGs are extremely valuable because they provide a real-time, non-invasive window into the brain’s activities. The machine uses tiny electrodes on a strip to measure neurological electrical activity, picking up on the regular rhythms of brain waves, which are microscopic voltage variations that represent neuronal activity. Depending on the state of consciousness, these brain wave patterns vary. For instance, alpha waves emerge during calm and relaxed states, theta and delta waves are predominant during sleep, and beta waves are linked to focused, alert wakefulness. By examining these wave patterns, researchers can identify if a person is awake, asleep, dreaming, meditating, or in a different state, allowing them to map the fluid landscape of consciousness with remarkable precision.

We often associate the waking state with the word “consciousness”. It is the baseline state of alertness, lucidity, and the processing of reality in real-time. In this state of consciousness, we experience the world through our senses, reflect on our thoughts, and respond to stimuli in the present. However, this baseline can fluctuate in accordance with attention, mood, fatigue, and focus. For example, if you were zoning out in the middle of class while the teacher was speaking and suddenly realized you haven’t been listening, that is considered a lapse in conscious awareness. During that time, you were awake — however, you were unable to take notice of your surroundings due to an error in processing.

Even in the sleeping state, we can consider ourselves conscious. When we sleep, consciousness doesn’t just shut off – it transforms. Sleep is a rich, complex cycle of brain states, particularly during the REM cycle, which is characterized by rapid eye movement. Neuroscientists have discovered that during REM sleep, the brain is nearly as active as it is when awake, correlating with the vivid dreams and increased bodily activity which define the traits of the REM cycle. However, the difference is seen during sleep, when the parts involved in sensory processing and memory are active, resulting in higher-level functions such as logic and self-awareness becoming less active. This partially contributes to the realism of dreams and compels scientists to believe that sleep can help reconsolidate memory. 

Dreams, especially lucid dreams,  often raise profound questions in the broad picture of consciousness. Why does the mind simulate alternate realities? Can we gain insights from them, or are they just neurological white noise? What is the awareness we feel in the fictional world when lucid dreaming? Factors such as dreams suggest that consciousness is not simply a binary switch. It’s a spectrum that becomes confusingly cryptic and grey in theory. 

Throughout history, humanity has often experimented with different methods to purposefully change the mind’s state of consciousness. These methods include hypnosis, meditation, and psychedelic experiences, which are temporarily altered states of consciousness or perception. Scientists have also produced chemicals known as psychoactive drugs which alter the chemistry of the brain and the body, producing similar psychedelic effects. According to brain scans, psychedelics such as psilocybin and LSD can alter regular communication between brain regions, resulting in novel patterns of self-experience and connectivity.  Users often describe feelings of unity, transcendence, or ego death, which is the loss of an individual’s sense of self – all experiences which can be grasped spiritually, but are increasingly being interpreted and analyzed neurologically. 

The unconscious mind, a concept formed by Sigmund Freud, also provides a label for the realm of hidden desires and fears. While modern psychology doesn’t embrace all aspects of Freud’s theory, it does recognize the idea that a significant portion of the processes of the mind happen beneath the level of conscious awareness. Habits, biases, and even complex decisions are made unconsciously. Freud’s theory is often called the iceberg theory, which describes three states of awareness and the psychological systems which interact within them.

The Iceberg theory remains one of the most iconic metaphors in psychology. Freud proposed that the mind’s structure could be viewed as an iceberg. At the tip of the iceberg is the conscious mind, which holds our thoughts, perceptions, and immediate awareness. Slightly underwater lies the preconscious, containing memories and information that aren’t in our immediate perception but can be accessed if needed.  Deeper is the unconscious, where Freud believed repressed fears, unacceptable desires (which he called the Oedipus Complex and in his book, described the aspirations of incest), and unresolved conflicts reside. They exert subtle influence over our thoughts and behavior, even without our knowledge. Within the context of these concepts, Freud also introduced the idea of the id, ego, and superego as interacting systems within the mind. The id represents primal and instinctual urges, the superego internalizes moral standards and ideals, and the ego mediates between these two desires and navigates the demands of reality. 

Although Freud's iceberg and other metaphors have long been used in psychology to study consciousness, contemporary neuroscientists take a biological approach to identify and quantify consciousness using the brain. Neural correlates of consciousness (NCCs) are the particular brain systems and activity patterns that appear to be connected to conscious experience. Others put forth more expansive models, like the Integrated Information Theory (IIT), which contends that consciousness results from a system's level of information integration – basically, a measurement of how cohesive and intricate an experience is. The Global Workspace Theory (GWT), on the other hand, sees consciousness as the center of attention where various brain regions vie to transmit data to the rest of the system. 

Although these theories differ in their explanations, they all point toward a common truth: consciousness is not a single concept; rather, it has many perceptions. Perhaps, the very pursuit of questioning consciousness in itself is a sign that we are awake. 

Citations:

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McLeod, Saul. “Freud’s Theory of Personality: Id, Ego, and Superego.” Simply Psychology, 13 Mar. 2025, www.simplypsychology.org/psyche.html .

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