such as brain anatomy.
A sub-dimension is the components that make up the dimension, such as gross anatomy (macro view) and histology (micro view). The gross anatomy represents what you can see with the naked eye. The histological anatomy is what you cannot see with the naked eye but can see microscopically. In this case, the anatomic dimension will have two sub-dimensions: the gross anatomic sub-dimension and the histological sub-dimension.
A domain consists of multiple dimensions that are grouped together for the purpose of establishing relationships. For example, the combination of anatomy and physiology to better understand how the brain functions will be considered one domain.
A level provides for an ordinal description in the form of “high to low,” “low to high,” “complex to simple,” or “simple to complex”. Examples of anatomic levels are the following hierarchical levels of the brain, i.e., the cerebral cortex (the highest level) vs brain stem (middle level) vs spinal cord (lowest level).
Sub-levels are the elements that comprise a level. The “head to tail” description of the title suggests that the levels of functioning on a hierarchy start from the most complex and go to the simplest, hence the title of this work.
Thinking through the concept of dimensions and domains is perhaps the most uninteresting part of this work, but it represents the core basis for BHET. Brain organization as a non-linear construct (not unidimensional) starts at a micro level and fully develops at a macro level. Like how computers are organized (see the chapter on dimensions), brain organization consists of certain dimensions. Each dimension, when combined with another dimension, can be conceptualized as a nervous system domain. For the purpose of simply understanding how to conceptualize such an organization, here are some domains with their individual dimensions that are critical to the BHET method:
Table # 10 – Domains and dimensions
| Domain | Dimension | |
| APD | Anatomic & Physiology Domain | • Anatomic• Physiologic |
| TSS | Time, Severity, and Stage Domain | • Time• Severity• Stage |
| IPO | Input – Process – Output Domain | • Input• Process• Output |
| SSD | Signs & Symptoms Domain | • Signs• Symptoms |
| PCB | Physical, Cognitive, and Behavioral Domain | • Physical• Cognitive• Behavioral or Neurobehavioral |
| TRO | Treatment, Recovery, and Outcome Domain | • Treatment• Recovery• Outcome |
2. Neuroprotection and prevention: Reducing the impact of an injury with various mitigating protection and prevention modalities can reduce the disruption in brain hierarchy and preserve function. Early intervention and restoration of the brain hierarchy as soon as possible is the best way to avoid any untoward outcomes following a TBI/concussion. Early treatment intervention forms the mantra of the treatment model so as to reduce the impact of such hierarchical disruption. Remember, “Time is brain.”
3. Compensatory and mitigation mechanisms: Following an injury, the nervous system adapts by compensating for certain deficiencies. This is at times crucial to the healing and reorganization of the nervous system. Because of the imbalance in the return of functions, some areas return faster than others, and this differential return of function often disrupts organized human behavior. Some compensatory mechanisms can be helpful while others can be harmful. If someone is exposed to an extreme experience that is life threatening or frightening, then the following compensatory mechanisms can set in:
a. They can run for their lives and escape to the point that their heart rate and breathing patterns can get out of control (positive because they escape!).
b. The person can become so frightened that they become anxious, have a panic attack, and faint. Anxiety occurs when they feel they have little or no control over a situation (negative compensation). Fainting is a way to avoid having any memories of the experience. The nervous system can compensate at just about every stage and level of injury. The more severe the injury and the less the hierarchical organization, the simpler and less sophisticated the compensation will be. Compensatory mechanisms, good or bad, are basic attempts of body systems to restore hierarchy and preserve itself for what the body determines is a higher good. However, this higher good may not be in the best interest of our wellbeing or the wellbeing of others. Fundamentally, clinicians, who have the knowledge of the nervous system’s tendencies and the ways it chooses to compensate, can use this knowledge to determine the severity of the injury, level of disorganization, treatment, and sometimes prognosis. Clinicians who understand these principles are in the best position to care for persons with TBI/concussions, as they generally will know what to expect. Compensation methods following TBI/concussions offer a kind of window into the state of the person’s nervous system. Many of the signs and symptoms that patients experience, in fact most of them, are compensating for something that is injured or being repaired or is forever affected. The brain has a tendency to form set patterns in response to certain levels, types, and locations of injury.
4. Timing and planning of treatment – Treatment planning and implementation should only be undertaken after a clear understanding of where there is disruption in the hierarchical organization of the nervous system and what the compensatory mechanisms are that the body has and will adapt to. There must also be an understanding of the interrelationships between the various levels of organizations where the disruptions are expressed. Simply treating the symptomatic manifestation of the disruption without a clear understanding of where such disruption occurs, the relationship of the area of disruption to other nervous system areas, stage of recovery, timing, treatment modality employed, and the domino effects that occur as a result of the disruption and treatment can lead to errors in treatment and additional negative effects. This will be addressed in Volume II.
5. Factors that impact recovery: There are several factors and variables impacting the level of hierarchical brain disruption and the potential for recovery following an injury. These factors include genetics, injury characteristics, general health, psychosocial aspects, environment, age, sex, prior training, education, support, discipline, capacity to recover, and personal characteristics of the individual. This will also be addressed in Volume II.
Understanding the Anatomical & Physiological Domain
Neuroanatomy and neurophysiology were among the most difficult but interesting courses I took in college and medical school. Those of you who might have taken these courses will relate. Irrespective of the complexity, in order to simplify our understanding of the nervous system as a construct, as well as in dimensions, sub-dimensions, and domains, is critical to how humans’ function.
Anatomic dimensions consist of “macro” and “micro” sub-dimensions of organization. First, the macro sub-dimensions are referred to as the gross anatomic sub-dimensions. These sub-dimensions describe structures that we can visualize with the naked eye when looking at brain structures. The micro sub-dimension, known as the histological sub-dimension, comprises the microscopic structures that come together to constitute the gross anatomic structures, which generally cannot be seen by the naked eye.
This is the most complicated part in the book and may require re-reading, especially for those who have a significant interest in the field. It addresses the anatomic hierarchical organization of the nervous system and the functioning of its components. To tell you that the next chapters (17-21) are simple would be a lie, but in order to go on to the more interesting parts of the book and have an understanding of how the brain is organized anatomically, these chapters are critical.
