It has been established that the frontal lobes play a major part in an individual’s decision making, planning, problem solving, social, emotional and behavioural skills. Consequently dysfunction of the frontal lobe can cause a wide range of symptoms (Kolb and Wishaw 1996) leading to relatively specific clinical dysfunction therefore a neuropsychological assessment is necessary to be carried out on the patient. The present study looks at the case of patient Mr. A who is reported to experience attention difficulties and problems with planning and organising after sustaining a head injury. Three neuropsychological tests have been used; WCST, TMT and TEA in order to identify the extent of the deficit. In line with previous research Mr. A’s performed poorly on tests and scored low in comparison to the normative scores. Other tests have also been suggested as well as strategies of rehabilitation for the patient.
Frontal lobe located at the front of the cerebral hemisphere is the largest lobe in the brain associated with an individual’s personality and emotional control. The frontal lobes are responsible for planning, organising, selective attention, personality, behaviour and emotions. As well as this the frontal lobes are also involved in motor function (Passingham 1995), Spontaneity of behaviour (Kolb and Milner 1981), initiation, judgement, impulse control (Milner 1964, Miller 1985), social and sexual behaviour (Damasio 1985). More specifically the right frontal lobe is associated with an individual’s sense of humour, self awareness, self face recognition and episodic memory (Stuss 1991, Fink et al 1996, Wheeler et al 1997, Levine et al 1998, Craik et al 1999, Keenan et al 1999, Shammi and Stuss 1999). It is the orbitofrontal cortex that arbitrates empathic, civil and socially appropriate behaviour (Mega and Cummings 1994). Furthermore it is also reported that executive processes of the prefrontal lobe are responsible for planning, monitoring, energizing, switching and inhibition (Stuss 2007).
In the recent years cognitive neuroscience studies have shown that damage to the frontal lobe can affect high level of cognitive functions as well as an individual’s personality, their social behaviour, personal memories and their self awareness (Alexander et al 1979, Brazzelli et al 1994, Damasio 1994, Adolphs et al 1995, Channon and Crawford 1999, Rogers et al 1999, Stuss et al 2001). Studies have also shown that damage to the prefrontal lobe particularly damage to the ventromedial frontal is associated with poor decision making (Eslinger and Damasio 1985, Harlow 1999, Ackerly 2000). In addition to this damage to the left or right orbitofrontal results in personality changes including indifference or impaired social judgement, impaired pragmatics, deficient effective responsiveness, poor self-regulation and lack of ability to relate social situations with personal experience (Nauta 1973, Stuss and Benson 1983, Kaczmarek 1984). Damage to the orbitofrontal cortex also results in the patient’s change of personality whereby they might become more irritable, labile, display lack of self restraint and fail to respond to the conventions of socially acceptable behaviour.
In some case studies patients have reported descriptions of behavioural changes that are related to social difficulties such as egocentrism, insensitivity to social cues, unresponsiveness to another’s opinion, lack of self restraint, diminished foresight, impaired self monitoring, a propensity to show signs of inappropriate affect and social withdrawal (Eslinger and Damasio 1985, Eslinger et al 1992, Price et al 1990). The famous case of Phineas Gage was the first case study to highlight the impact of frontal lobe damage on an individual’s personality, decision making and social behaviour (Damasio 1994). Phineas Gage suffered an extreme injury to the frontal lobe when a 13 pound, 3-foot-long tamping rod when through his head; entering through his left cheek and exiting through the midline of his skull. Astonishingly after the event Gage still had the ability to walk, communicate and remain lucid and was examined by Dr Harlow (1848) who noticed the changes in his behaviour. In his report Harlow identified that from previously being identified as a smart, efficient, dependable and capable foreman by his employers and diligent, honest and well liked by friends, after his accident Gage became fitful, irreverent, foulmouthed liar, impatient, extravagant, anti social and profane especially when advice was given to him that he didn’t like (Harlow 1868).
Another case study presented by Eslinger and Damasio (1985) is of patient EVR, who obtained bilateral damage to his orbitofrontal cortex during surgical removal of a brain tumour. Despite EVR’s superior or above average intelligence, memory, language and his ability to discuss complex issues such moral dilemmas, foreign affairs, economy and financial matters in an intelligent and sensible manner after his surgery his decision making ability became impaired. He found it hard to make simple decisions such as what clothes to wear or what restaurant to eat at, Damasio (1995) talks more about this in his somatic marker hypothesis.
A more modern case similar to Phineas Gage but caused by a bullet injury reported by Vertosick (1996) is that of Stephen who shot himself in the head and straight after not only remained alive but semiconscious. The bullet entered Stephens’s right temple and exited through his left forehead damaging his frontal lobes. At the time of the incident Stephen was a 15 year old, difficult, rowdy teenager being treated for alcoholism and with a list of juvenile arrests. After his accident his behaviour improved as he no longer argued with his parents or teachers and was doing reasonably well at school compared to his marks previously. He also displayed little desire to do anything outside the house and his urinary incontinence improved.
It has been made clear that dysfunction of the frontal lobe can cause a wide range of symptoms (Kolb and Wishaw 1996) leading to relatively specific clinical dysfunction therefore a detailed neurobehavioral evaluation is necessary to be carried out. Many neuropsychological tests can be used to measure any dysfunction of frontal lobe such as finger tapping, Wisconsin Card Sorting Test (WCST), measures of verbal and figural fluency as well as many more. These tests play a major part in conducting a neuropsychological assessment of a patient. The present study aims to assess and indentify the dysfunctions described in the case study of patient Mr. A by selecting the appropriate and relevant tests. Drawing upon the literature I am expecting to find Mr. A to present low scores on the tests performed on him. The tests I have chosen are; WCST, Trial Making Test Parts A and B and the Test of Everyday Attention.
The design is a case study.
The participant is Mr. A (See case study 1- Assessment of frontal lobe function, appendix 1).
Wisconsin Card Sorting Test (WCST) – Consisting of 128 cards each displaying a geometrical figure that varies in dimensions of colour, form and number. The participant is required to sort the cards according to the dimension shown on the cue card.
Trial making tests A and B – Part A requires participant to connect in order a series of number circles and part B requires the participant to connect in order a series of number and letter circles in number and alphabetical order.
Test of Everyday Attention (TEA- adults) – Five subtests were used; “Elevator Counting”; where participant is required to imagine they are trapped in an elevator and have to say which floor they arrive at by counting a series of tape presented tones. “Elevator counting with distraction”; where the participant is asked to count the low tones whilst ignoring the high tunes. “Visual elevator”; participants are asked to count up and down in the pretend elevator as they follow a series of doors visually presented. “Telephone search”; where participants are required to look for certain symbols whilst going through a telephone directory and “Telephone search while counting”; where participants search through the telephone directory whilst counting the tones from the tape recorder.
` The WCST is one of the most common tests used in clinical and experimental psychology (Fuster 1997, Kimberg, D’Esposito and Farah 1997 Kolb and Whishaw 1996, Lezak 1995, Milner 1963, Mountain and Snow 1993, Spreen and Strauss 1998, Stuss & Benson 1986) and was chosen because it is the most appropriate in this case as it measures the ability to learn concepts therefore it will help assess Mr. A’s planning and problem solving skills. The test has shown specific sensitivity to frontal lobe lesions and was introduced as a test of prefrontal lobe function by Milner (1963).
Mr A is reported to be easily distracted which suggests that he has poor attention therefore the test chosen to assess his attention is Trial Making Test A and B; a useful test in helping to identify dysfunction of frontal lobe (Gaudino, Geisler and Squires 1995) as well as a reliable and valid test in measuring distributed attention (Bradford 1992, Corrigan and Hinkeldey 1987). Part A of the test measures speed and attention (Carlton and Daniel 1990) whereas part B assesses the patient’s skill to shift strategy and measures executive function reflecting the activity of frontal lobes (Bradford 1992).
Attention difficulties are a very common result of frontal lobe dysfunction. The Test of Everyday Attention (Robertson et al 1996) was used to measure the patient’s attention, out the 8 subtests 5 were selected; the ones considered most relevant to the patient. The “Elevator Counting” measures sustained attention sensitive to the frontal lobes and the “Elevator Counting with Distraction” is a test of auditory selective attention. The “Visual Elevator” test is similar to the WCST and measures attention switching and finally the “Telephone search” and the “Telephone search while counting” measures divided attention.
To establish if a patient’s performance on the neuropsychological test is normal or not a normative scored has to be recognized first so there is something to compare the patients score against. In order to avoid misdiagnosis factors such as age, education, medical history and gender need to be considered when trying to establish a normative score.
The WCST displays deficits in the patient’s ability as well as executive dysfunctions like verbal fluency. The results of the tests display that deficits are a result of the patients inability to follow the rules of the task such as following the plan given or their inability to plan an approach to solve the task at hand (Gouveia et al, 2007). The WCST is considered to be sensitive to the frontal lobe lesions therefore it shows evidence of a patient’s preservative thinking. Furthermore patients with frontal lobe damage make a higher number of preservative errors (Milner 1963), Mr A is therefore predicted to make a higher number of preservative scores on the WCST.
Trial Making Test A and B:
The trial making test (TMT) is reported to be sensitive to brain damage (Reitan and Wolfson 1995) and in order for successful completion requires executive functioning as well as other cognitive abilities such as psychometer speed and visual scanning as mentioned before. The higher number of scores presented will reveal greater impairment in the patient (Corrigan and Hinkeldey 1987, Gaudino, Giesler and Squires 1995, Lezak, Howieson and Loring 2004, Reitan 1958), it is therefore predicted that Mr. A will score highly on both Trial Making Test A and B.
Three different types of errors have been identified in TMT this is exactly what is expected from Mr. A; going on to the incorrect number or letter on either part of the test, inability to go from a number to letter and vice versa on part B and finally going to the incorrect nearby circle on either part of the test (Mahurin et al 2006, McCaffrey et al 1989).
Test of Everyday Attention (TEA):
The subtests chosen on the TEA measured 3 factors; selective attention, sustained attention and switching attention (Robertson et al 1996). It has been reported that those who are good at problem solving are better at storing and processing information in working memory and therefore will be good at attention switching which is measured by the “Visual Elevator” which requires the patient to switch their attention between alternative possibilities to come to a conclusion (Byrne 2005, Johnson-Laird and Byrne 1991, 2002). Attention also contributes to helping patients decide what aspect of the problem to focus on. Consequently successful problem solvers will switch their strategy once they realise that the strategy they have adopted is not working (Davidson 1995). A study by Chan (2000) highlighted that patients with deficits within the frontal lobe lesions scored lower on the test than the control group. In line with this it is assumed that Mr. A will display low scores on all of the subtests.
The results suggest that the personality and behavioural change of Mr. A is a consequence of dysfunction within the frontal lobe lesions. However the low scores obtained on the tests could be for a number of reasons and not necessarily due to frontal lobe dysfunction. For example some studies have suggested poor results obtained on the WCST may not be due to the dysfunction of frontal lobe but could be a result of deficits in the working memory (Barcelo et al 1997). Other findings also showed that results differed between different demographic backgrounds therefore a multi factorial nature is advised when carrying out an assessment on a patient (Wiegner and Donders 1999). Furthermore it has also been suggested that the performance on the WCST may not be correlated with frontal lobe damage at all the reason being that other areas of the brain are also involved in abstract reasoning (Reitan and Wolfson 1994).
Similarly research has also shown has that age, education and intelligence affect the scores of Trial Making Test (Spreen and Strauss 1998). It has been reported that performance on the test declines with the increase in age (Ivnik, Malec, Smith, Tangalos, & Petersen 1996; Kennedy 1981; Rasmusson et al 1998). No normative data exists which covers all the factors of age, education, intelligence and cultural differences therefore the data cannot always be used to confirm that the scores produced by the patient are due to the dysfunction (Mitrushina et al 1999). The results of the TMT are also difficult to interpret because they are common amongst individuals within the control group (Ruffolo et al 2000) and some studies have failed to distinguish the control group from those that suffered head injury based on their scores (Klusman, Cripe and Dodrill 1989).
In comparison to conventional measures of attention the TEA has several advantages mainly because the tasks are more relevant to everyday life; it consists of a wide variety of subtests that cover different aspects of attention and was developed accordingly to the theories of attention (Posner and Petersen’s 1990). However there are limitations for example the manual does not provide enough information about the reliability of the test.
In order to establish a normative score an interview should be conducted beforehand which is a major part of the assessment in which factors such as age, education and intelligence need to be addressed as well as the affect of the injury on the patient (Lezak et al 2004). Additionally norms in relation to IQ level are also necessary in order to establish whether if the patient has deficit or not. As well as this research according to cultures needs to be conducted because the normative scores cannot be generalised to all cultures. Consequently recommendations for future research will be to establish a normative score with healthy participants taking into account the above mentioned factors so that there is something to compare the patients score with. There are many other neuropsychological tests that are used to measure frontal lobe dysfunction that could have been carried out on the patient. For example Tower of Hanoi (Simon 1975) which would have shown the patient’s ability of problem solving and The Block Design Test (Hutt 1932) which would show whether or not the frontal lobes are functioning properly. Another recommendation could be use a larger range of tests.
In conclusion although there is research to prove that neuropsychological testing does work, on the other hand research has also shown that neuropsychological tests don’t always work; as in some cases patients with frontal lobe damage and cognitive deficits have displayed good performance on a standard neuropsychological test because they have nothing to do with everyday life. Regardless of this a neuropsychological evaluation is necessary as it highlights to what extent the dysfunction is and the neuropsychologist can then make appropriate cognitive plans for the patients as well as plans for the patients families in helping and working with them. An example of this can be in advising the family whether if the home setting is suitable or appropriate for the patient or not. Patients with frontal lobe damage also need constant supervision due to their inability to follow plans or to plan and carry out tasks and due to their lack of impulse control. Additionally the patient also needs to be advised of rehabilitation strategies such as meditation (Herzog et al 1990 and Lazar et al 2000) and yoga (Naveen et al, 1997 and Telles et al, 1993).