The human frontal lobe is relatively large in mass and is less restricted in movement than the posterior part of the brain. It is a component of the cerebral system, which supports goal-directed behavior. These lobes are often referred to as parts of the brain responsible for the ability to decide between good and bad choices, as well as recognize the consequences of different actions. Because of its location in the anterior part of the head, the frontal lobe is arguably more susceptible to injury. After frontal lobe injury , the individual's ability to make good choices and recognize consequences is often disrupted. Memory impairment is another common effect associated with frontal lobe injury, but this effect is poorly documented and may or may not be the result of incorrect testing. Damage to the frontal lobe may lead to increased irritability, which may include mood swings and an inability to regulate behavior. In particular, frontal lobe injuries can cause deficits in executive function, such as anticipation, target selection, planning, initiation, sequencing, monitoring (detecting faults), and self-correction (initiating new responses). A widely reported case of frontal lobe injury is that Phineas Gage, a railroad worker whose left frontal lobe was damaged by a large iron rod in 1848 (though Gage's next personality change is almost always exaggerated).
Video Frontal lobe injury
Efek neuropsikologis
Memori dan perhatian
Patients with damaged frontal lobes often complain of minimal memory damage. Because of this, frontal lobe injury has long been associated with memory problems, although little evidence suggests this relationship is true. In fact, when patients with such injuries are tested using standard memory tests, they often score under normal circumstances. However, close relatives of these same patients can describe a considerable memory problem. Disparity occurs because it is not the memory system itself that is affected, but the frontal lobe function that facilitates working memory. Working memory is closely involved with the ability to hold attention. Working memory is not just how much information you can retain in a short period of time; this describes the primary memory, and a fraction of the working memory associated with it. An important part of working memory is secondary memory, where an individual takes information. Those with high working memory can do this retrieval even when interrupted by other tasks. Patients with damaged frontal lobes exhibit lower working memory and, therefore, lower ability to retrieve information from their secondary memory.
Risk taking
Improved impulsivity, risk taking or both are often seen in individuals after frontal lobe damage. The two related terms differ in impulsivity is the disinhibition response, whereas risk taking is related to reward based decision making aspects. Put simply, impulsive people will make decisions quickly, without considering the consequences, which ultimately lead to a lack of self-control. Conversely, risk takers will see the consequences but not burden them; they will jump on prize opportunities even though the chances of receiving the prize are very slim. Increased risk taking among damaged frontal lobe patients can be directly observed during gambling, and gambling tasks have been developed to measure the behavior.
Maps Frontal lobe injury
Specifying Effects
Test type
Before more advanced technology emerged, scientists tested individual behavior using more low-tech means. As technology advances, so does the tests that scientists make to evaluate one's cognitive function In testing the behavioral effects of frontal lobe injury, however, many tests are still very simple and do not involve highly advanced technology.
Gambling assignment
This test has an inverse relationship between the possibility of getting the prize and the value of the gift itself; that is, low probability but high reward or high probability but low reward. Thus, actual gambling skills are not tested, but only a preference for high rewards despite the risks. In one way to implement this, a set of cards will be presented face down to the individual being tested; one of the cards will be the victory card, and the other, the loser. The cards will then be continually removed from the stack and added back randomly, during which time the winning card can be anywhere. Subjects tested were told they could stop the process anytime and flipped the card; if the winning card is in the pile, they win points. However, the catch is that more points are given when the card is less available; but when less cards are present, chances are the winning card is in the less pile. Risk takers are those who get higher rewards (more points), though they tend to actually receive the reward. They choose higher, less likely rewards, lower, more likely gifts. Subjects with frontal lobe injury exhibit such behavior when tested.
Wisconsin Sorting Card Test (WCST)
The Wisconsin Card Sorting Test (WCST) can be used in conjunction with other tests to speculate on the possible dysfunction of the prefrontal cortex, the frontal area of ​​the frontal lobe, which plays an important role in the executive function. However, since the days of modern medicine and brain imaging, WCST has proven to be inaccurate and inconclusive in diagnosing frontal lobe damage.
The WCST test should specifically measure the individual's competence in abstract reasoning, and the ability to change the problem-solving strategy when necessary.
Saccade
Saccade is a rapid movement of the eye in a certain direction. In its simplest form, there are two types of saccade tests that are set up where the only requirement is eye movement: procade and antisaccade. In prosaccade, participants are asked to quickly look to a point in response to some interesting gestures, such as flashing lights. Because there is a powerful evolutionary force that works to automatically focus on stronger stimuli (greater power), this type of test does not invoke individual executive controls; Therefore, prosaccade is irrelevant when testing the effects of frontal lobe damage on executive cognitive control and working memory. In contrast, the antisaccade test requires not only to ignore flashing cues, but to also look in the opposite direction. This task calls for strong inhibition of responses and plans and implements eye movements that conflict with instincts. In an anti-saccade test, an individual must set goals to ignore these instincts and continue to '' maintain '' these goals. Those with frontal lobe injuries show lower working memory, and therefore usually do not test well in antisaccade tests.
Disadvantages in Testing
While impulsive and risk-taking behaviors are both commonly observed after frontal lobe injury, these properties are difficult to evaluate and measure without some degree of subjectivity. The definition of these characteristics alone is not entirely clear, nor is it always approved. As a result, the methods for measuring these behaviors are often different, and these should be considered when comparing data/results from different sources. Therefore, it is worth noting how to interpret different results.
It is also important to remember that a single test, such as WCST, can not be used to measure the effects of frontal lobe injury, or aspects of cognitive function that may affect, such as working memory; various tests should be used. Subjects may be good in one task but show dysfunction in overall executive function. Similarly, test results can be made misleading after testing the same individual for long periods of time. Subjects may be better off in a task, but not because of enhanced executive cognitive functioning. He/she may only learn some strategies to perform this particular task that makes it no longer a good measurement tool. & Lt; reference & gt;
Patients with damaged frontal lobes often complain of minimal memory damage, although when patients are tested using standard memory tests, they often get a normal score. The gap could be the result of these standard test limits. As is possible, the scientific community may not compare the right group of people. Little is understood about the function of the frontal lobes that facilitate memory, but what is clear is that a deeper study of brain injury patients is needed. Because most studies compare them with brain injury (whether the frontal lobes or not) and those not, the scientific community is not sure whether certain memory disorders are specific to frontal lobe injury, or only traumatic brain injury in general. There are many factors to consider when examining the effects of traumatic brain injury, such as the nature of the injury and its causes; but the severity of the injury appears to be the most important in affecting specific memory damage for frontal lobe damage. Patients suffering from mild traumatic brain injury with frontal lobe damage appear to be only slightly affected, if affected altogether.
Frontal lobe injuries have been shown to lead to a decrease in the ability to combine temporally disaggregated events (time-separated), and remember information in the correct context. However, standard testing may mask or exaggerate the likelihood of damage because the patient is strictly regulated, as is their free behavior. Many times, these are behaviors that are thought to be directly related to frontal lobe disorders, when in fact, these patients suffer from completely different problems, such as attention, anxiety, sleep disorders, etc.
Conclusion
The main conclusion that can be agreed upon is that the test should continue to be investigated; as society progresses, better tests should be designed. Without an appropriate test to assess traumatic brain injury patients with frontal lobe damage in particular, we may misinterpret frontal lobe function, particularly the role it plays in memory.
See also
- Frontal lobe disorder
- Gourmand syndrome
- Frontal Lobotomy
References
External links
- Locational Dysfunction: Brain Dysfunction: Merck Manual Home Edition
- Science Daily: Frontal Lobe Damage Can Affect A Person's Ability To 'Keep Work'
See also
- Phineas Gage Rail railway construction survivor of a large iron rod pushed through his left frontal lobe in 1848
- Apatis expressive
- Brain damage
- Lobotomy
Source of the article : Wikipedia
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