The structure of the brain is complex and the injuries it can suffer are many. Facing the front of your skull or forehead, are the frontal lobes (there are two because the brain is divided left and right) although they are united with the corpus collosum. To the sides are the temporal areas; the rear, the occipital. The parietal is located across the top and above the occipital.
The frontal lobes involve initiation of action and behaviors, problem solving, inhibition of behaviors, organization, attention and concentration, mental flexibility, speaking (expressiveness), planning and anticipation, self-monitoring, motor planning, executive functioning, judgment, emotions generally, awareness of abilities and limitations, emotional response and stability, language, personality, word associations and meaning, memory for habits and motor activity, and, significantly, the tracking and sense of self and identity. Injury to the frontal lobes (prefrontal cortex), may produce any of the following impairments:
- Loss of spontaneity in social interactions
- Loss of flexibility in thinking (mental rigidity)
- Distractibility – easy distraction without ability to prevent distraction
- Concentration difficulties
- Diminished abstract reasoning and imagination
- Expressive difficulty – language usage and word finding (Broca’s aphasia)
Injury to the frontal lobes and the parietal lobe (the top of the head), it’s possible some of the following impairments may appear:
- Naming objects (anomia)
- Writing words (agraphia)
- Reading or recognize words, no comprehension of written language (alexia)
- Loss of ability to recognize numbers, do math problems, or count (acalculia)
- Focus visual attention
- Reading (alexia)
- Poor hand-eye coordination
- Confused left-right orientation
- Trouble organizing
- Poor self-reflection
- Emotional rigidity
- Drawing difficulty
- Poor visual perception
- Self-care or hygiene (apraxia)
The temporal lobes, on both sides, are low, roughly above and behind the area where the area where the ears and the aural nerves exit the brain. People struck on the side of the head, which may occur in a traffic collision (side impact), baseball, football, boxing, soccer, slip and falls, physical abuse, and others, may develop symptoms such as deficits in:
- Understanding language (receptive language)
- Problems with organization
Sequencing things and thoughts
The parietal lobes provide for senses of touch, differentiation (identification) of size, shapes, and colors, spatial perception (e.g., depth visual perspective, object relations to each other), visual perception (e.g. color hues, shades, object perspective and relations, night and peripheral). Since the parietal lobes are located above and to each side of the occipital region, an injury affecting the parietal lobes may also affect the occipital lobes. Alteration of the ability to perceive in the topical areas described can cause a person to miscomprehend what is happening in front of him or her, misunderstand the relationship of objects and distances between objects, and misperceive distance and height. These symptoms may cause a person to seem imbalanced.
The occipital lobes generally comprise the vision area and an injury there can cause blindness or other vision problems in one eye or both. The cerebellum is a critical part of the brain providing persons with sense of balance, coordination, and skilled motor activity. Injury to the cerebellum is often permanent and frequently fatal. The brain stem, located just below the cerebellum and the point at which the spinal cord is linked to the brain, allows people to breathe, maintain heart rate, controls arousal and consciousness, sleep and wake cycles, and attention and concentration.
Accidents involving pedestrians or sudden and extreme acceleration or deceleration may cause the brain stem to sever from the brain, resulting in death. In that even unconsciousness is instantaneous and the injured person is unaware. My mother suffered a rupture of an aneurysm in the circle of Willis, causing massive hemorrhaging which over a few days involved the cerebellum. Her symptoms were initially a sense of confusion and disorientation, inability stand, gradual loss of speech, and within four hours, unconsciousness. Surgery was done to relieve intracranial pressure, but death was certain.
The basal ganglia, caudate nucleus, reticular, and putamen (pons) are crucial to my story because one of my strokes caused damage to the left side of the brain in the pons and basil ganglia. The crucial amygdala and thalamus are in this region but are part of the limbic system. The basil ganglia structure includes part of the brain stem. The system of brain components comprising the basil ganglia sets deep within the brain, just above and encompassing part of the cerebellum. Hemorrhage in the area can cause motor problems (e.g., Parkinson’s disease, tic, tremor, chorea) and it is directly supplied with blood by the circle of Willis. The earlier stroke I suffered was left sided, higher, in the deep region of the temporal lobe and angling downward to the basal ganglia.
The components of the basil ganglia have different functions. The putamen “receives most of the inputs from motor and somatosensory areas… .” The caudate nucleus responds to fewer movement inputs and is related prominently to cognitive functions and, since it loops back to the prefrontal cortex, findings would be similar to those of a frontal lobe injury. I studied this soon after my adult strokes were diagnosed. It remains a frightening topic of discussion and thought. It is most likely that the frontal skull injury at age four caused some brain damage which resolved due to the plasticity of my brain in infancy and the healing power of the brain with time. By the time I was nineteen, my brain had reached its full growth, however, the stroke then suffered was above and not in the basal ganglia. The two strokes at age forty-five were more serious, but caused relatively mild symptoms