PsychologicalReports, 1990, 67, 435-438. @ Psychological Reports 1990
EMOTIONAL IMPACT O N TRAIL MAKING TEST PERFORMANCE ' CARLTON S. GASS AND SUSAN K. DANIEL Veterans Administration Hospital,
Mlornz,
Florida
Summary.-This study assessed the effect of emotional factors on Trail Making Test Part B performance for a sample of 105 neuropsychological referrals for whom there was no neurodiagnostic evidence of brain damage. Trails B scores declined in reladon to elevated MMPI scores on Scales 6, 7, and 8, though only nine patients performed within the impaired range. The results suggest that (a) Trails B performance is resilient to a variety of emotional influences, (b) psychotic symptoms and severe anxiety impede Trails B performance, though rarely to the extent caused by brain damage, and (c) the MMPI provides objective criteria that help rule out emotional effects on Trails B performance.
The Trail Making Test was originally part of the Army Individual Test Battery and has since become widely employed as part of the Halstead Reitan Battery. The test has two parts. Part A requires visual scanning, numeric sequencing, and visuomotor speed. Part B (Trails B) further requires letter sequencing and mental double tracking in alternating between number and letter series. Given the test's brevity, ease of administration, and sensitivity to brain damage, it is commonly used as a screening instrument for the detection of organic impairment. I n addition, the Trails B assesses the capacity for mental flexibility in managing more than one stimulus or thought at a time and shifting the course of an ongoing activity (8). This study examined the effects of emotional factors as assessed using the MMPI on the T r d s B performance of a neuropsychological referral sample. Although both tests are widely employed for the purposes of screening as well as part of a more comprehensive evaluation, little is known regarding the relation between MMPI variables and Trails B performance. Similarly, the role of emotional factors in Trails B performance has received little attention, despite the test's popularity as a screening instrument. To the extent that emotional factors are related to scores on Trails B, it is conceivable that the MMPI could be used to enhance its use as a screening device and improve interpretations of scores that occur in the context of a more comprehensive neuropsychological test battery. Previous research has examined differences in Trails B scores between organics and psychiatric patients, showing conflicting results using schizophrenics (1, 15) and mixed psychiatric samples (2, 9). I t has been suggested that performance on this and other neuropsychological tests may be fairly resilient to all but the more severe forms of psychopathology, such as chronic 'Gratitude is expressed to Cherylan Tanner and Elbert W. Russell for their assistance in data collection. Correspondence concerning this article should be addressed to Carlton S. Gass, VA Medical Center (546/116B3, 1201 NW 16th Street, Miami, Florida 33125.
436
C. S. GASS & S. K. DANIEL
schizophrenia (7). There is evidence that global indices of cognitive functioning, such as the WAIS Verbal and Performance Scale IQs, correlate marginally, at best, with MMPI scores of brain-impaired samples (3, 4, 5 , 10). However, the Trds B scores of chronic schizophrenics have been correlated with MMPI scores on several clinical scales (14). The manner in which emotional factors may influence Trails B performance in a sample of neuropsychological referrals who lacked any demonstrable evidence of organic pathology was addressed in the present investigation. Subjects were 100 male and 5 female veterans who completed the MMPI and HalsteadReitan Battery as part of a neuropsychological evaluation at the Miami Veterans Administration Hospital. Their average age was 47.6 yr. (SD = 13 9) and education was 12.6 yr. (SD = 2.7). They were referred from the (inpatient) Psychiatry (41%). (outpatient), Mental Hygiene (23%), Alcohol and Drug Dependency (15%), and Neurology (21%) Services of the hospital. None of these patients had evidence of brain damage as determined by staff neurologists who evaluated their histories and performed standard neurodiagnostic tests. The extent of neuropsychological impairment as assessed using the Average Impairment Rating Scale (131 was within the normal to borderline range with an average of 1.30 (SD=0.4). MMPI profiles were screened for invalidity if they met any of the widely employed criteria: more than 30 unanswered items, F scale elevation > 89T, K > 69T, and F raw score -K raw score > 16. A divenity of emotional characteristics was represented in this sample as evidenced by composite scores on the clinical scales, reported in means and standard deviations: Scale 1 (Hs: 71.4 and 19.51, Scale 2 (D: 79.9 and 19.2), Scale 3 (Hy: 69.6 and 15), Scale 4 (Pd: 68.5 and 15.1), Scale 6 (Pa: 62.8 and 12.51, Scale 7 (Pt: 70.5 and 16.6), Scale 8 (Sc: 74.6 and 19.11, and Scale 9 (Ma: 62.6 and 10.8).
RESULTS The influence of emotional factors was initially explored by performing multiple correlation analyses of MMPI K-corrected T scores on patients' Trails B scores using the MGLH module of SYSTAT (16). A multiple R of .61 had significant beta coefficients on education (2.45), age (.87) and Scale 8 (.69). Some attenuation of the correlations was anticipated due to nonlinearity, having included a lower range of T scores in the analysis. Therefore, a second analysis compared the composite MMPI scores of patients as divided into two groups of 30 patients based on the quality of their Trails B performance, excluding 45 middle-range scoring patients to enhance discriminative power and minimize the likelihood of a Type 2 error. Group 1 scored less than 63, and Group 2 greater than 99. Analyses of covariance were performed on MMPI scores, with age and education as covariates. As a precautionary measure in making multiple comparisons, a higher significance level (.01) was used for rejecting the null hypothesis. The results showed significant intergroup differences on Scales 6, 7, and 8 (ps< .Ol). The approximate point a t which T scores on these scales were associated with significant performance decrements on Trails B was further assessed. To do this, Trails B raw scores were corrected for age and education using
437
EMOTIONAL INFLUENCE O N TRAIL MAKING B
Russell's (11) norms. Patients were divided into four groups based on their T scores within each of the three MMPI scales (Table 1). MEANS AND
MMPI Scale
Paranoia (6)
Schizophrenia (8)
TABLE 1 STANDARD DEVIATIONS OF TRAILS B ADJUSTEDRAW SCORES CLASSIFIED BY m I SCORING RANGE n
Tscore
F
P
31.6 27.7 27.7 33.5
4.55
,005
67.4 75.4 75.0 93.0
31.3 33.1 25.7 30.2
3.14
.03
68.3 65.6 87.0 87.7
25.1 32.3 30.0 29.3
4.28
,007
Trails B
Range
M
SD
28 28 24 25
41-53 54-63 64-70 71 above
66.5 69.0 83.8 92.2
25 24 33 23
34-56 57-70 71-81 82 above
25 27 26 27
38-59 60-73 74-84 85 above
Analyses of variance confirmed the absence of intergroup age or educational differences. Mean comparisons of Trails B scores across the four groups yielded significant trends on all three scales. Post hoc contrasts indicated a significant decline in Trails B scores as Scale 6 reached the 64-70 T-score range, Scale 8 the 74-84 range, and Scale 7 the 82 and above range, with no further decline above these ranges. The application of Russell's (11) empirically derived cutting score of 110 yielded 9 of 105 patients within the impaired range on Trails B, with 7 of 9 having some combination of elevated (T>69) scores on Scales 6, 7, and 8 .
DISCUSSION These findings support the notion that with few exceptions, Trails B performance is resilient to the effects of emotional factors. I n view of the diversity of psychopathology represented in this sample, it is noteworthy that only nine patients scored within the impaired range. I n particular, depressive symptoms, which are often assumed to impede performance through slowing, decreased motivation, or inattention, did not have an effect in this sample. Other studies have found similar results for minimal influence of depression on attentional and memory tests (6, 17). Emotional characteristics reflected in elevated scores on Scales 6, 7, and 8 were significant, however. I t appears from these findings that the primary means by which psychopathology affects Trails B performance involves disturbed concentration or confusion secondary to a thought disorder or extreme anxiety. Task demands of alternating attention and double tracking, in
438
C. S. GASS
& S.
K. DANIEL
particular, may be vulnerable to these symptoms. Nevertheless, for most patients these symptoms as inferred from MMPI scores did not affect performance to the extent found in brain-impaired samples. Clinicians should exercise caution in attributing low scores on Trails B to emotional factors, particularly as inferred from elevated MMPI scores. Rather than using the MMPI to infer an emotional effect, it appears that the MMPI might provide a more accurate means for ruling out emotional effects in cognitive test performance. As applied to Trails B, specifically, these results suggest that a combination of normal-range scores on Scales 6, 7, and 8 provides strong evidence against a functional explanation for poor test performance, even in the presence of other elevated scores. Further study of the relation between MMPI scores and neuropsychological test performance may ultimately provide clinicians with a more objective means of evaluating the protocols of patients who have known or suspected brain dysfunction. REFERENCES 1. BOLL, T. J . (1974) Psychological differentiation of atients with schizophrenia versus lateralized cerebrovascular, neoplastic, or traumatic %rain damage. Journal of Abnormal Psychology, 83, 456-458. 2. BURGESS,M. M., KODANAZ, A,, ZIEGLER,D., & GREENBERG, H . (1970) Prediction of brain damage in two clitucal populations. Perceptual and Motor Skills, 30, 523-532. 3. DEMEN, S. R., & REITAN,R. M. (1977) MMPI correlates of adaptive ability deficits in patients with brain lesions. Journal of Nervous and Mental Disease, 165, 247-254. 4. GASS, C. S., & RUSSELL,E. W. (1985) MMPI correlates of verbal-intellectual deficits in patients with left hemisphere lesions. Journal of Clinical Psychology, 41, 664-670. 5. GASS,C. S., & RUSSELL,E. W. (1987) M W I correlates of performance-intellectual deficits in patients with right hemisphere lesions. Journal of Clinical Psychology, 43, 484-489. 6. GASS,C S . RUSSELL,E. W., & HAMILTON,R. A. (1990) Accuracy of MMPI-based inferences regnrd~ngmemory and concentration in closed head trauma patients. Psychological Assessrncnl Journal of Consulting and Clinical Psychology, 2, 175-178. 7. HEATON,R. K., BAADE,L. E., &JOHNSON, K. L. (1978) Neuropsychological test results associated with psychiatric disorders in adults. Psychological Bulletin, 85, 141-162. 8. LEZAK,M. (1983) Nerrropsycbological assessment. New York: Oxford Univer. Press. R. D. (1967) An evaluation of the Trail Making Test. Journal of 9. ORGEL,S., & MCDONALD, Consulting Psychology, 31, 77-79. 10. OSMON,D. C., & GOLDEN,C. (1978) Minnesota Multiphasic Personality Inventory correlates of neumpsycho1Ogicdbeki.t. International Journal of Neuroscience, 8. 113-122. 11. RUSSELL,E. W. (19871 Age and education corrections for neumpsychological test raw scores derived m the manner described in Russell (1988). Klnpuhl~shedraw data) 12. RUSSELL,E. W. (1988) Renorming Russell's version of the Wechsler Memory Scale. Journal of Clinrcal and Experimental Neuropsychology, 10, 235.249 13. R u s s e u , E. W., NEURINGER, C., & GOLDSTEIN, G. (1970) Assessment of brain damage: a neur~ps~chological key approach. New York: Wiley Interscience. 14. SMITH, T. E., & BOYCE,E. M. (1962) The relationship of the Trail Making Test to psychiatric symptomatology. Journal of Clinical Psychology, 18, 450-454. 15. TATE, G. T. (1964) Validity of three objective tests in evaluating organicity in schizophrenia. Newsletter for Research in Psychology, 6 , 18-20. 16. WILKINSON, L. (1988) SYSTAT: the system for statistics. Evanston, IL: SYSTAT, Inc. , M., L ~ L EM. , M., SCATES,S., & BLOCKMAN, N. (1987) Memory com17. W L L X W SJ. plaints and abihties among depressed older adults. Journal of Consulting and Clinical Psychology, 55, 595-598.
Accepted August 13, 1990.
EMOTIONAL IMPACT O N TRAIL MAKING TEST PERFORMANCE ' CARLTON S. GASS AND SUSAN K. DANIEL Veterans Administration Hospital,
Mlornz,
Florida
Summary.-This study assessed the effect of emotional factors on Trail Making Test Part B performance for a sample of 105 neuropsychological referrals for whom there was no neurodiagnostic evidence of brain damage. Trails B scores declined in reladon to elevated MMPI scores on Scales 6, 7, and 8, though only nine patients performed within the impaired range. The results suggest that (a) Trails B performance is resilient to a variety of emotional influences, (b) psychotic symptoms and severe anxiety impede Trails B performance, though rarely to the extent caused by brain damage, and (c) the MMPI provides objective criteria that help rule out emotional effects on Trails B performance.
The Trail Making Test was originally part of the Army Individual Test Battery and has since become widely employed as part of the Halstead Reitan Battery. The test has two parts. Part A requires visual scanning, numeric sequencing, and visuomotor speed. Part B (Trails B) further requires letter sequencing and mental double tracking in alternating between number and letter series. Given the test's brevity, ease of administration, and sensitivity to brain damage, it is commonly used as a screening instrument for the detection of organic impairment. I n addition, the Trails B assesses the capacity for mental flexibility in managing more than one stimulus or thought at a time and shifting the course of an ongoing activity (8). This study examined the effects of emotional factors as assessed using the MMPI on the T r d s B performance of a neuropsychological referral sample. Although both tests are widely employed for the purposes of screening as well as part of a more comprehensive evaluation, little is known regarding the relation between MMPI variables and Trails B performance. Similarly, the role of emotional factors in Trails B performance has received little attention, despite the test's popularity as a screening instrument. To the extent that emotional factors are related to scores on Trails B, it is conceivable that the MMPI could be used to enhance its use as a screening device and improve interpretations of scores that occur in the context of a more comprehensive neuropsychological test battery. Previous research has examined differences in Trails B scores between organics and psychiatric patients, showing conflicting results using schizophrenics (1, 15) and mixed psychiatric samples (2, 9). I t has been suggested that performance on this and other neuropsychological tests may be fairly resilient to all but the more severe forms of psychopathology, such as chronic 'Gratitude is expressed to Cherylan Tanner and Elbert W. Russell for their assistance in data collection. Correspondence concerning this article should be addressed to Carlton S. Gass, VA Medical Center (546/116B3, 1201 NW 16th Street, Miami, Florida 33125.
436
C. S. GASS & S. K. DANIEL
schizophrenia (7). There is evidence that global indices of cognitive functioning, such as the WAIS Verbal and Performance Scale IQs, correlate marginally, at best, with MMPI scores of brain-impaired samples (3, 4, 5 , 10). However, the Trds B scores of chronic schizophrenics have been correlated with MMPI scores on several clinical scales (14). The manner in which emotional factors may influence Trails B performance in a sample of neuropsychological referrals who lacked any demonstrable evidence of organic pathology was addressed in the present investigation. Subjects were 100 male and 5 female veterans who completed the MMPI and HalsteadReitan Battery as part of a neuropsychological evaluation at the Miami Veterans Administration Hospital. Their average age was 47.6 yr. (SD = 13 9) and education was 12.6 yr. (SD = 2.7). They were referred from the (inpatient) Psychiatry (41%). (outpatient), Mental Hygiene (23%), Alcohol and Drug Dependency (15%), and Neurology (21%) Services of the hospital. None of these patients had evidence of brain damage as determined by staff neurologists who evaluated their histories and performed standard neurodiagnostic tests. The extent of neuropsychological impairment as assessed using the Average Impairment Rating Scale (131 was within the normal to borderline range with an average of 1.30 (SD=0.4). MMPI profiles were screened for invalidity if they met any of the widely employed criteria: more than 30 unanswered items, F scale elevation > 89T, K > 69T, and F raw score -K raw score > 16. A divenity of emotional characteristics was represented in this sample as evidenced by composite scores on the clinical scales, reported in means and standard deviations: Scale 1 (Hs: 71.4 and 19.51, Scale 2 (D: 79.9 and 19.2), Scale 3 (Hy: 69.6 and 15), Scale 4 (Pd: 68.5 and 15.1), Scale 6 (Pa: 62.8 and 12.51, Scale 7 (Pt: 70.5 and 16.6), Scale 8 (Sc: 74.6 and 19.11, and Scale 9 (Ma: 62.6 and 10.8).
RESULTS The influence of emotional factors was initially explored by performing multiple correlation analyses of MMPI K-corrected T scores on patients' Trails B scores using the MGLH module of SYSTAT (16). A multiple R of .61 had significant beta coefficients on education (2.45), age (.87) and Scale 8 (.69). Some attenuation of the correlations was anticipated due to nonlinearity, having included a lower range of T scores in the analysis. Therefore, a second analysis compared the composite MMPI scores of patients as divided into two groups of 30 patients based on the quality of their Trails B performance, excluding 45 middle-range scoring patients to enhance discriminative power and minimize the likelihood of a Type 2 error. Group 1 scored less than 63, and Group 2 greater than 99. Analyses of covariance were performed on MMPI scores, with age and education as covariates. As a precautionary measure in making multiple comparisons, a higher significance level (.01) was used for rejecting the null hypothesis. The results showed significant intergroup differences on Scales 6, 7, and 8 (ps< .Ol). The approximate point a t which T scores on these scales were associated with significant performance decrements on Trails B was further assessed. To do this, Trails B raw scores were corrected for age and education using
437
EMOTIONAL INFLUENCE O N TRAIL MAKING B
Russell's (11) norms. Patients were divided into four groups based on their T scores within each of the three MMPI scales (Table 1). MEANS AND
MMPI Scale
Paranoia (6)
Schizophrenia (8)
TABLE 1 STANDARD DEVIATIONS OF TRAILS B ADJUSTEDRAW SCORES CLASSIFIED BY m I SCORING RANGE n
Tscore
F
P
31.6 27.7 27.7 33.5
4.55
,005
67.4 75.4 75.0 93.0
31.3 33.1 25.7 30.2
3.14
.03
68.3 65.6 87.0 87.7
25.1 32.3 30.0 29.3
4.28
,007
Trails B
Range
M
SD
28 28 24 25
41-53 54-63 64-70 71 above
66.5 69.0 83.8 92.2
25 24 33 23
34-56 57-70 71-81 82 above
25 27 26 27
38-59 60-73 74-84 85 above
Analyses of variance confirmed the absence of intergroup age or educational differences. Mean comparisons of Trails B scores across the four groups yielded significant trends on all three scales. Post hoc contrasts indicated a significant decline in Trails B scores as Scale 6 reached the 64-70 T-score range, Scale 8 the 74-84 range, and Scale 7 the 82 and above range, with no further decline above these ranges. The application of Russell's (11) empirically derived cutting score of 110 yielded 9 of 105 patients within the impaired range on Trails B, with 7 of 9 having some combination of elevated (T>69) scores on Scales 6, 7, and 8 .
DISCUSSION These findings support the notion that with few exceptions, Trails B performance is resilient to the effects of emotional factors. I n view of the diversity of psychopathology represented in this sample, it is noteworthy that only nine patients scored within the impaired range. I n particular, depressive symptoms, which are often assumed to impede performance through slowing, decreased motivation, or inattention, did not have an effect in this sample. Other studies have found similar results for minimal influence of depression on attentional and memory tests (6, 17). Emotional characteristics reflected in elevated scores on Scales 6, 7, and 8 were significant, however. I t appears from these findings that the primary means by which psychopathology affects Trails B performance involves disturbed concentration or confusion secondary to a thought disorder or extreme anxiety. Task demands of alternating attention and double tracking, in
438
C. S. GASS
& S.
K. DANIEL
particular, may be vulnerable to these symptoms. Nevertheless, for most patients these symptoms as inferred from MMPI scores did not affect performance to the extent found in brain-impaired samples. Clinicians should exercise caution in attributing low scores on Trails B to emotional factors, particularly as inferred from elevated MMPI scores. Rather than using the MMPI to infer an emotional effect, it appears that the MMPI might provide a more accurate means for ruling out emotional effects in cognitive test performance. As applied to Trails B, specifically, these results suggest that a combination of normal-range scores on Scales 6, 7, and 8 provides strong evidence against a functional explanation for poor test performance, even in the presence of other elevated scores. Further study of the relation between MMPI scores and neuropsychological test performance may ultimately provide clinicians with a more objective means of evaluating the protocols of patients who have known or suspected brain dysfunction. REFERENCES 1. BOLL, T. J . (1974) Psychological differentiation of atients with schizophrenia versus lateralized cerebrovascular, neoplastic, or traumatic %rain damage. Journal of Abnormal Psychology, 83, 456-458. 2. BURGESS,M. M., KODANAZ, A,, ZIEGLER,D., & GREENBERG, H . (1970) Prediction of brain damage in two clitucal populations. Perceptual and Motor Skills, 30, 523-532. 3. DEMEN, S. R., & REITAN,R. M. (1977) MMPI correlates of adaptive ability deficits in patients with brain lesions. Journal of Nervous and Mental Disease, 165, 247-254. 4. GASS, C. S., & RUSSELL,E. W. (1985) MMPI correlates of verbal-intellectual deficits in patients with left hemisphere lesions. Journal of Clinical Psychology, 41, 664-670. 5. GASS,C. S., & RUSSELL,E. W. (1987) M W I correlates of performance-intellectual deficits in patients with right hemisphere lesions. Journal of Clinical Psychology, 43, 484-489. 6. GASS,C S . RUSSELL,E. W., & HAMILTON,R. A. (1990) Accuracy of MMPI-based inferences regnrd~ngmemory and concentration in closed head trauma patients. Psychological Assessrncnl Journal of Consulting and Clinical Psychology, 2, 175-178. 7. HEATON,R. K., BAADE,L. E., &JOHNSON, K. L. (1978) Neuropsychological test results associated with psychiatric disorders in adults. Psychological Bulletin, 85, 141-162. 8. LEZAK,M. (1983) Nerrropsycbological assessment. New York: Oxford Univer. Press. R. D. (1967) An evaluation of the Trail Making Test. Journal of 9. ORGEL,S., & MCDONALD, Consulting Psychology, 31, 77-79. 10. OSMON,D. C., & GOLDEN,C. (1978) Minnesota Multiphasic Personality Inventory correlates of neumpsycho1Ogicdbeki.t. International Journal of Neuroscience, 8. 113-122. 11. RUSSELL,E. W. (19871 Age and education corrections for neumpsychological test raw scores derived m the manner described in Russell (1988). Klnpuhl~shedraw data) 12. RUSSELL,E. W. (1988) Renorming Russell's version of the Wechsler Memory Scale. Journal of Clinrcal and Experimental Neuropsychology, 10, 235.249 13. R u s s e u , E. W., NEURINGER, C., & GOLDSTEIN, G. (1970) Assessment of brain damage: a neur~ps~chological key approach. New York: Wiley Interscience. 14. SMITH, T. E., & BOYCE,E. M. (1962) The relationship of the Trail Making Test to psychiatric symptomatology. Journal of Clinical Psychology, 18, 450-454. 15. TATE, G. T. (1964) Validity of three objective tests in evaluating organicity in schizophrenia. Newsletter for Research in Psychology, 6 , 18-20. 16. WILKINSON, L. (1988) SYSTAT: the system for statistics. Evanston, IL: SYSTAT, Inc. , M., L ~ L EM. , M., SCATES,S., & BLOCKMAN, N. (1987) Memory com17. W L L X W SJ. plaints and abihties among depressed older adults. Journal of Consulting and Clinical Psychology, 55, 595-598.
Accepted August 13, 1990.
