A reduced level of consciousness affects non-conscious processes
A Fontan1, L Lindgren2, T Pedale1
1Department of Integrative medical biology, Umeå Center for Functional Brain Imaging, Umeå University, Sweden.
Neuroimage
|September 12, 2021
Summary
Investigating consciousness, this study found that Propofol sedation impacts both conscious and non-conscious brain processing. Understanding sedation
Area of Science:
- Neuroscience
- Cognitive Science
- Psychology
Background:
- Consciousness is a fundamental aspect of human existence, yet its nature remains enigmatic.
- The term "consciousness" encompasses both the content (phenomenology) and level (arousal) of awareness.
- The relationship between the content and level of consciousness is not fully understood.
Purpose of the Study:
- To empirically investigate the relationship between the level and content of consciousness.
- To determine how manipulating conscious and non-conscious stimuli affects brain activity under sedation.
- To explore the neural underpinnings of conscious and non-conscious processing.
Main Methods:
- Utilized functional magnetic resonance imaging (fMRI) to measure brain activity.
- Manipulated the level of consciousness using Propofol sedation.
- Presented stimuli both consciously and non-consciously to participants.
Main Results:
- Propofol sedation differentially affected conscious and non-conscious processing.
- Conscious processing was altered in higher-order brain regions, including the intraparietal sulcus.
- Non-conscious processing was affected in sensory areas, with the opposite pattern observed compared to conscious processing.
Conclusions:
- Sedation impacts both conscious and non-conscious neural processes, but at different hierarchical levels.
- The findings necessitate a re-evaluation of studies on consciousness that use sedation without considering both conscious and non-conscious processing.
- Future research should account for the differential effects of sedation on various processing levels to better understand consciousness.
Related Concept Videos
01:15Subconsciousness and No Awareness
418
The concept of subconscious awareness refers to the processing of information below the level of conscious thought, which significantly influences both behaviors and decisions. It is also known as waking subconscious awareness. This complex level of cognition operates without the direct awareness of the individual, facilitating rapid and simultaneous handling of multiple information streams.
An illustrative example of subconscious processing is its role in problem-solving. Often, individuals...
An illustrative example of subconscious processing is its role in problem-solving. Often, individuals...
418
01:19High-Level and Low-Level Awareness
444
Controlled processes in human consciousness represent high-alert mental states where individuals deliberately focus their attention on achieving specific goals. Controlled processes can be seen in situations like mastering new technology, where a person might become so absorbed that they ignore surrounding distractions. Such processes involve selective attention, requiring one to concentrate on particular elements of experience while disregarding others. These are governed by executive...
444
01:23Understanding Consciousness
570
Consciousness can be defined as the state of being aware of and able to think about one's existence, sensations, and surroundings. It encompasses two major components: awareness and arousal. Awareness pertains to the recognition of environmental stimuli and internal states. At the same time, arousal refers to the physiological readiness to engage with these stimuli, which varies significantly between states like sleep and wakefulness.
Sleep, a crucial state, is characterized by reduced...
Sleep, a crucial state, is characterized by reduced...
570
01:06Altered States of Awareness
626
Altered states of consciousness represent significant deviations from one's normal mental state. These deviations can range from subtle changes in awareness to profound transformations in perception, thought processes, and sensory experiences. Altered states of consciousness can be triggered by various factors, including drug use, meditation, hypnosis, illness, or even intense fatigue.
The ingestion of substances like stimulants or hallucinogens leads to chemical alterations in the brain...
The ingestion of substances like stimulants or hallucinogens leads to chemical alterations in the brain...
626
01:22Stages of General Anesthesia
947
Various sedation levels offer significant advantages in facilitating procedural interventions for patients undergoing medical or invasive surgical procedures. These levels span from anxiolysis to general anesthesia, providing a spectrum of sedative effects to cater to specific patient needs. Anxiolysis reduces anxiety and is achieved through minimal sedation, enabling patients to remain awake and responsive while feeling more at ease during the procedure. This level can benefit minor...
947
01:15Subliminal Perception
433
Subliminal perception refers to the processing of sensory information that occurs below the level of conscious awareness. Researchers study subliminal perception by presenting a stimulus, such as a word or image, very quickly, typically around 50 milliseconds. This rapid presentation is often followed by another stimulus, such as a pattern of dots or lines, which blocks further mental processing of the initial stimulus. As a result, if participants cannot identify the initial stimulus better...
433