Phi complex
Encyclopedia
The phi complex is a brain rhythm
in the awake human brain
that appears to serve various social functions. Phi is one of several brain rhythms in the awake human brain that coordinate human behavior
. "Phi" operates in the 10-Hz band (ten oscillations per second), and is located above the right centro-parietal cortex
. It consists of two components, one favoring independent behaviors, and the other favoring interpersonal coordination between people.
The brain wave patterns of the phi complex are consistent with those of waves produced in the human mirror neuron
system. The phi complex may reflect the influence of one person upon another's behavior, with phi-1 expressing the inhibition of the human mirror neuron system and phi-2 its enhancement.
(FAU), in one of the first studies in the field of social neuroscience
, have identified neural signatures of effective, real-time coordination between people. FAU researchers have recorded, measured and analyzed both behavior
and brain activity simultaneously in two interacting humans that could provide insight into neurological disorders, such as autism
and schizophrenia
. The research used the conceptual framework and methods of coordination dynamics.
Using specially designed dual-electroencephalogram recordings, Tognoli and her colleagues tested the brain activity of two people simultaneously performing continuous finger motion. Initially, two subjects were asked to rhythmically wag their fingers at their own preferential pace, but were prevented from seeing each other's hands. Then the barrier placed between them was then removed, so they could see each other while continuing to wag their fingers. When subjects were allowed to see one another's fingers moving, they sometimes adjusted their own movements and synchronized, and sometimes they did not, behaving independently.
The researchers believe that the use of dual EEG recordings to observe the phi complex could help scientists better understand what triggers leader/follower behaviors and male/female relationships. The researchers reported that 62% of respondents synchronized their movements upon being exposed to one another's finger-wagging, but 38% were unaffected and continued gesturing independently.
The study demonstrated a clear reduction in occipital lobe
alpha wave
and mu wave
rhythms during social interaction. The evident suppression was independent of whether or not behavior was coordinated. In contrast, a pair of oscillatory components (phi-1 and phi-2) above the right centro-parietal cortex distinguished effective from ineffective coordination. An increase of phi-1 favored independent behavior and increase of phi-2 favored coordinated behavior.
According to Kelso "What this research suggests is that a unique pattern can be seen in the brains of two people interacting and that these brain activities distinguish independence from cooperation. This new brain rhythm that we have discovered and termed the 'phi complex' actually distinguishes when you're socially interacting and when you're not."
Electroencephalography
Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...
in the awake human brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
that appears to serve various social functions. Phi is one of several brain rhythms in the awake human brain that coordinate human behavior
Human behavior
Human behavior refers to the range of behaviors exhibited by humans and which are influenced by culture, attitudes, emotions, values, ethics, authority, rapport, hypnosis, persuasion, coercion and/or genetics....
. "Phi" operates in the 10-Hz band (ten oscillations per second), and is located above the right centro-parietal cortex
Parietal lobe
The parietal lobe is a part of the Brain positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different modalities, particularly determining spatial sense and navigation. For example, it comprises somatosensory cortex and the...
. It consists of two components, one favoring independent behaviors, and the other favoring interpersonal coordination between people.
The brain wave patterns of the phi complex are consistent with those of waves produced in the human mirror neuron
Mirror neuron
A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour of the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other...
system. The phi complex may reflect the influence of one person upon another's behavior, with phi-1 expressing the inhibition of the human mirror neuron system and phi-2 its enhancement.
Research
Researchers from Florida Atlantic UniversityFlorida Atlantic University
Florida Atlantic University, also referred to as FAU or Florida Atlantic, is a public, coeducational, research university located in , United States. The university has six satellite campuses located in the Florida cities of Dania Beach, Davie, Fort Lauderdale, Jupiter, Port St. Lucie, and in Fort...
(FAU), in one of the first studies in the field of social neuroscience
Social neuroscience
Social neuroscience is an interdisciplinary field devoted to understanding how biological systems implement social processes and behavior, and to using biological concepts and methods to inform and refine theories of social processes and behavior. Humans are fundamentally a social species, rather...
, have identified neural signatures of effective, real-time coordination between people. FAU researchers have recorded, measured and analyzed both behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
and brain activity simultaneously in two interacting humans that could provide insight into neurological disorders, such as autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
and schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
. The research used the conceptual framework and methods of coordination dynamics.
Using specially designed dual-electroencephalogram recordings, Tognoli and her colleagues tested the brain activity of two people simultaneously performing continuous finger motion. Initially, two subjects were asked to rhythmically wag their fingers at their own preferential pace, but were prevented from seeing each other's hands. Then the barrier placed between them was then removed, so they could see each other while continuing to wag their fingers. When subjects were allowed to see one another's fingers moving, they sometimes adjusted their own movements and synchronized, and sometimes they did not, behaving independently.
The researchers believe that the use of dual EEG recordings to observe the phi complex could help scientists better understand what triggers leader/follower behaviors and male/female relationships. The researchers reported that 62% of respondents synchronized their movements upon being exposed to one another's finger-wagging, but 38% were unaffected and continued gesturing independently.
The study demonstrated a clear reduction in occipital lobe
Occipital lobe
The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area 17, commonly called V1...
alpha wave
Alpha wave
Alpha waves are neural oscillations in the frequency range of 8–12 Hz arising from synchronous and coherent electrical activity of thalamic pacemaker cells in humans...
and mu wave
Mu wave
Mu waves, also known as the comb or wicket rhythm, are electromagnetic oscillations in the frequency range of 8–13 Hz and appear in bursts of at 9 – 11 Hz. Mu wave patterns arise from synchronous and coherent electrical activity of large groups of neurons in the human brain...
rhythms during social interaction. The evident suppression was independent of whether or not behavior was coordinated. In contrast, a pair of oscillatory components (phi-1 and phi-2) above the right centro-parietal cortex distinguished effective from ineffective coordination. An increase of phi-1 favored independent behavior and increase of phi-2 favored coordinated behavior.
According to Kelso "What this research suggests is that a unique pattern can be seen in the brains of two people interacting and that these brain activities distinguish independence from cooperation. This new brain rhythm that we have discovered and termed the 'phi complex' actually distinguishes when you're socially interacting and when you're not."
See also
- Beta waveBeta waveBeta wave, or beta rhythm, is the term used to designate the frequency range of human brain activity between 12 and 30 Hz . Beta waves are split into three sections: High Beta Waves ; Beta Waves ; and Low Beta Waves...
- Delta waveDelta waveA delta wave is a high amplitude brain wave with a frequency of oscillation between 0–4 hertz. Delta waves, like other brain waves, are recorded with an electroencephalogram and are usually associated with the deepest stages of sleep , also known as slow-wave sleep , and aid in characterizing the...
- EpilepsyEpilepsyEpilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
- Holonomic brain theoryHolonomic brain theoryThe holonomic brain theory, originated by psychologist Karl Pribram and initially developed in collaboration with physicist David Bohm, is a model for human cognition that is drastically different from conventionally accepted ideas: Pribram and Bohm posit a model of cognitive function as being...
- SMRSensorimotor rhythm- Description :The Sensory Motor Rhythm is brain wave rhythm. It is an oscillatory idle rhythm of synchronized electromagnetic brain activity. It appears in spindles in recordings of EEG, MEG, and ECoG over the sensorimotor cortex. For most individuals, the frequency of the SMR is in the range...
- Sensory Integration DysfunctionSensory Integration DysfunctionSensory integration dysfunction is a neurological disorder characterized by a neurological sensory integration deficit. The more current diagnostic nosology uses the term sensory processing disorder to describe this condition....
- Theta wave
External links
- sciencedaily.com - 'New Brain Neuromarker May Shed Light On Autism And Schizophrenia', Science DailyScience DailyScience Daily is a news website for topical science articles. It features articles on a wide variety of science topics including: astronomy, exoplanets, computer science, nanotechnology, medicine, psychology, sociology, anthropology, biology, geology, climate, space, physics, mathematics,...
(May 15, 2007)