In the prior section, we pointed out that slow frequencies are broadcast from sets of nuclei near the center of the brain. Neurons in the cortex don’t “make” theta or delta rhythms. They can resonate to them when they are not performing a task, as you might tune in to a transmission on radio, television or internet.
The only frequencies actually produced by cortical neurons are the fast ones, the Betas. When a task requires processing, cortical neurons “de-synchronize” from their rhythm generators and specific areas burst into action. They receive from other neurons, process the information and send it along. Beta speeds (12-38 Hz) tend to be local, often in bursts and linking over short distances. Beta represents high use of energy in areas where it is needed.
When a brain’s cortical neurons are overly excited or sensitized, beta activity can be seen over larger areas and longer periods. A lot more energy is being used than is required.
When a brain is using a fast-dominant state—or when locked in it—we can describe how that person is likely to appear or feel. There is a relationship between my brain’s frequency activation patterns and my mental and emotional state.
Internal or External Locus of Awareness: Fast-dominant brains can focus on internal processes—or on external tasks.
Language-Based Processing: High frequency thinking and communicating is done with words. Reading/listening/speaking/writing with detail and organization is a strength. Brains stuck in this mode are likely filled with words, criticisms and commentaries.
Process Decisions: Choices are made via sequences and steps. They can be explained. Intuition is not trusted and may be blocked from participation. A brain stuck in fast frequencies may be more rigid, controlling, judgmental.
High energy Moods: Emotions tend toward the hotter: enthusiasm, anxiety, fear, anger.
Motivated socially: Faster frequencies tend toward extroversion. When the brain is stuck in fast, there can be weakness in social boundaries and recognizing limits.
Detail thinker: In a brain stuck in fast frequencies, this strength can appear as inability to feel and relate emotionally—sometimes inability to decide and act. Bureaucracy results.
Sleep Issues: May have insomnia in sleep onset, or inability to fall asleep again after waking in the night. May grind teeth and sleep restlessly. May not feel rested after sleep due to frequent awakenings or failure to enter deeper sleep states.
Beta1 (LoBeta) (12-15 Hz) is the slowest Beta frequency. It is a fast frequency in all sites except those in the Central Strip (C3, Cz and C4), crossing the midpoint of the head from side-to-side. In this area of the brain (known as the Sensory-Motor Cortex) 12-15Hz is called Sensory-Motor Rhythm (SMR). We’ll talk more about SMR in the section on middle frequencies.
Beta2 (15-22 Hz) is sometimes considered “Functional Beta”, since it is most often present when a cognitive task is being performed. It is often split into two bands as well. 15-18 Hz is the workhorse of the beta speeds, and most of us, when we are producing it, feel ourselves sharp and focused. 19-22 Hz is sometimes experienced as intense curiosity and involvement, but it also verges on a feeling of anxiety for some brains.
Beta3 (23-38 Hz) HiBeta is an extremely high level of energy, an excitability—well above what is useful for most tasks. It is sometimes called hyper-vigilance—an intense state of being completely on edge in expectation of impending danger. Rarely in one’s life that state may be useful—even necessary—but, outside of a war zone of one sort or another, those times would be rare. More than a few brains get stuck in this exhausting pattern.
We pay special attention to sudden surges of 23-38 Hz activity, which can alert us that the brain is shifting into fight or flight mode—emergency response—even in an eyes-closed relaxation task.
When and where
Beta frequencies are strong in the front of the head, and especially over the left hemisphere. Right and Rear areas with high beta activation are often correlated with anxiety, anger, sometimes fear. They also correlate with various sleep disturbances.
Beta levels usually drop relative to other frequencies during eyes-closed relaxation tasks. They should become more important in the EEG at cognitive task. Beta activates and de-activates in small areas as needed. Inability to activate—or to de-activate—can have extensive effects on our lives.