From the Guidelines
Stroke symptoms correlate directly to the affected brain region, with specific areas controlling distinct functions, and when blood flow is interrupted, the neurons in that area cannot function properly, resulting in symptoms that reflect the lost function of that particular brain region. When the frontal lobe is damaged, patients may experience weakness or paralysis on the opposite side of the body, difficulty speaking (if the left side is affected), and changes in behavior or personality 1. Damage to the parietal lobe causes sensory problems, difficulty with spatial awareness, and neglect of the affected side 1. Temporal lobe strokes result in memory problems, language difficulties (if on the dominant side), and hearing disturbances 1. Occipital lobe involvement causes visual field defects or blindness 1. Strokes affecting the cerebellum lead to coordination problems, balance difficulties, and ataxia 1. Brain stem strokes are particularly dangerous, causing problems with breathing, heart rate, consciousness, and often affecting multiple body functions simultaneously 1. These correlations exist because specific brain regions control distinct functions, and when blood flow is interrupted during a stroke, the neurons in that area cannot function properly, resulting in symptoms that reflect the lost function of that particular brain region. The side of the body affected is typically opposite to the side of the brain damaged due to the crossing of neural pathways in the brain. Some specific correlations include:
- Left-sided weakness, paresthesia or sensory loss, left-sided neglect, abnormal visual-spatial ability, monocular blindness that affects the right eye, and right homonymous hemianopsia (visual loss that involves the right visual field) with ischemia or infarction in the distribution of the right internal carotid artery or middle cerebral artery 1
- Right-sided weakness, paresthesia or sensory loss, aphasia, and monocular blindness that affects the left eye or left visual field with ischemia or infarction in the distribution of the left internal carotid artery or middle cerebral artery 1
- Ataxia, cranial nerve deficits, visual field loss, dizziness, imbalance, and incoordination with ischemia or infarction in the vertebrobasilar system 1. It is essential to note that these correlations are not absolute and can vary depending on the individual and the specific location and extent of the stroke. However, understanding these correlations can help healthcare professionals to quickly identify the affected area and provide appropriate treatment. In clinical practice, the most recent and highest quality study 1 suggests that biomarkers of cognitive function, including executive functioning, are not ready for immediate broad implementation in clinical trials, and further study and validation of biomarkers that explain current state and future change in cognitive functions are a significant priority area for development.
From the Research
Symptoms of Stroke
The symptoms of stroke can be categorized based on the location and type of stroke. Some common symptoms include:
- Sudden unilateral numbness or weakness of face, arm, or leg, especially on one side of the body 2
- Speech difficulty 3, 2
- Visual trouble 2
- Sudden onset of a severe headache, which is commonly associated with subarachnoid hemorrhage 3
Correlation with Brain Regions
The correlation between symptoms and brain regions is as follows:
- Speech disturbance is often associated with lesions in the left hemisphere of the brain, particularly in the Broca's area or Wernicke's area 3
- Weakness on one-half of the body is often associated with lesions in the contralateral hemisphere of the brain, particularly in the motor cortex 3
- Visual trouble can be associated with lesions in the occipital lobe or the optic nerve 2
- Sudden onset of a severe headache can be associated with subarachnoid hemorrhage, which can occur in various locations, including the basal cisterns or the cortical surface 3
Importance of Early Recognition
Early recognition of stroke symptoms is crucial for timely treatment and improved clinical outcomes 2. Public awareness campaigns have promoted the typical warning symptoms of stroke, including sudden unilateral numbness or weakness, speech difficulty, and visual trouble 2. However, it is also important to recognize that stroke can have an unusual clinical presentation, known as "stroke chameleons," which can mimic other disorders 2.