the following are my thoughts on how a person may be impacted by damage to the four major lobes within the brain.
When viewing the brain, the overall cortex is typically divided into four distinct sections based on the anatomical features of the area. The four major divisions, or lobes, are the frontal lobe, the parietal lobe, the temporal lobe, and the occipital lobe (Gazzaniga, Irvy, & Mangun, 2018). Current research maintains that each of these lobes are responsible for a variety of functions. That being said, damage to each of these areas is believed to be associated with specific consequences depending on the area in which the damage was received. We will look at each of these areas one at a time to understand their function and the impact that damage to each section could potentially have.
Firstly, the most anterior, or most forward, is the frontal lobe. This lobe contains two major subdivisions: the motor cortex and the prefrontal cortex (Gazzaniga, Irvy, & Mangun, 2018). The motor cortex is responsible for the generation of neural signals which result in movement, specifically relating to the initiation, planning and the sensory guidance for movement. On the other hand, the prefrontal cortex is associated with executive cognitive functions, specifically social behavior, motivation, planning and organizing (Gazzaniga, Irvy & Mangun, 2018). With that in mind, damage to this area may have significant impact on an individual. According to particular case studies, individuals who have experienced lesions in their prefrontal cortex have reported a plethora of impacts to their day-to-day functionality. For example, damage to the frontal lobe has been associated with inability to regulate social behaviors, inability to control emotions, general feelings of distress, inability to plan, and a lack of overall motivation. Additionality, lesions in this area have also been associated with troubles with complex physical movements, such as the playing of a musical instrument (Barrash et al., 2018;Fourie, Van Der Merwe, & Swart, 2016).
Secondly, posterior to the frontal lobe and above the temporal lobe is the parietal lobe. This lobe is responsible for the receipt of sensory information, specifically as it relates to touch, pain, and spatial awareness (Gazzaniga, Irvy, & Mangun, 2018). Damage, or lesions, to this lobe in the brain are associated with a variety of impacts. Damage to this lobe may impact one’s overall sense of spatial awareness. For example, this may result in inability to conceptualize one’s environment, lack of body awareness, and in extreme cases the experience of out of body experiences (Gazzaniga, Irvy, & Mangun, 2018). Additionally, research also suggests that damage to this area may impact a person’s ability to recall memories. Researchers found that when the parietal lobe was damaged, a person will still be able to recall information, however, they will lose confidence in what they are recalling (Hower et al., 2014). For example, when asked to recall a specific memory, a person may begin doubting crucial information, or leaving out rich details, that would have immediately come to them before damage to the parietal lobe.
Thirdly, posterior to the parietal lobe, at the rear end of the brain, is the occipital lobe. This lobe is primarily associated with the ability to visually perceive the world. This information is fed to the visual vortex via sensors within the retina and this area of the brain is tasked with processing this incoming information (Gazzaniga, Irvy, & Mangun, 2018). As this is an extremely important area of the brain, damage experienced here can come at a major cost. For example, research indicates that those who experience lesions on the occipital lobe experience a plethora of visual inaccuracies. Some with lesions in this area have experienced visual hallucinations, blurred vision, issues with visual categorization and blind spots. Others have reported loss of visual acuity and issues identifying specific colors (Paradowski et al., 2013; Fourie, Van Der Merwe, & Swart, 2016).
Lastly, the most inferior lobe, or the lobe at the bottom, is the temporal lobe. This lobe’s primary goal is to process information from the auditory cortex. In other words, this lobe analyzes and perceives the neural stimulation that is sent to the brain via our cochlea (Gazzaniga, Irvy, & Mangun, 2018). With that in mind, damage to this area may result in a number of auditory abnormalities. For example, research indicates that lesions to this area may result in the inability to identify specific sounds heard in our environment. Additionally, lesions in this area may also result in auditory hallucinations, or disturbances involving sounds that are not actually being perceived (Fourie, Van Der Merwe, & Swart, 2016). Interestingly, damage to this lobe has also been associated with issues with memory. For example, those with damage to this area have reported issues with long-term memory, altered emotions, and issues with comprehending language (Fourie, Van Der Merwe, & Swart, 2016).