- Email: [email protected]
Paralinguistic aspects of auditory comprehension in aphasia
BRAIN
AND
LANGUAGE
Paralinguistic
7,
(1979)
164-li’;
Aspects of Auditory in Aphasia
Comprehension
BOLLER, MONROE COLE, P. BART VRTUNSKI, MARIAN PATTERSON. AND YOUNGJAI KIM
FRANGOIS
Cleveland
Veterans
Administration
Hospital
Eight severe aphasics were given sentences with either emotional or neutral content, presented once directly by the examiner and once via a tape recorder. Sentences with emotional content produced a greater number of responses than their neutral counterparts. Sentences spoken by the exaininer also produced a significantly greater number of responses than the same items originating from a tape recorder. These results confirm the view that elements not related to the linguistic aspects of a message (and therefore referred to as paralinguistic) play a significant role in auditory comprehension,
There is increasing interest in trying to understand better the nature of the comprehension impairment that exists in virtually every aphasic patient. Greatest attention has been paid thus far to the role of linguistic factors, i.e., phonemic (Blumstein, Baker, & Goodglass, 1977; Naeser, 1976), syntactic, and semantic (Pizzamiglio & Appicciafuoco, 1971); in auditory comprehension. It has also been shown, however, that elements not related to the linguistic aspect of the message, and therefore referred to as “paralinguistic” (Boller, Kim, & Mack, 1977), play a role in auditory comprehension. Goldstein (1948), for example, stressed that patients who often cannot perform correctly in a test situation may be able to perform the same task in daily situations. Other studies have examined the importance of such factors as context (Bransford & Johnson, 1973; Stachowiak, Huber, Poeck, & Kerschensteiner, 1977; Lebrun, in press), speed (Gardner, Albert, & Weintraub, 1975), mode of presentation (Green & Boller, 1974), and emotional content of utterances (Wechsler, 1973). These studies have established the importance of paralinguistic factors, even though the precise role they play in the auditory comprehension of aphasics remains to be more clearly defined. It has recently been stressed (Boller & Green, 1972; Green & Boller, 1974) that in order to study the comprehension of aphasics, especially those with the most severe impairment, one must pay attention to more Requests for reprints should be sent to: Dr. Franqois Boller, Neurobehavior land VA Hospital, 10701 East Boulevard, Cleveland, OH 44106. 164 0093-934x/79/020164-1 1$02.00/O Copyright All rights
($I 1979 by Academic Press, Inc. of reproduction in any form reserved.
Unit, Cleve-
AUDITORY
165
COMPREHENSION
than whether their response (verbal or gestural) is correct. Other aspects of the patient’s performance, such as a puzzled look or a burst of laughter, or a performance which, although incorrect, is related to the question asked or the command given, may be just as important in determining how much has been understood. In the present study, we wanted to evaluate the role of emotional content and mode of presentation of a series of sentences on the comprehension of severe aphasics. We hypothesized that if content of the sentences affected the way in which patients responded, there would be a greater number of responses to sentences with emotional content than to neutral sentences even if the responses might not be correct. We also hypothesized that sentences presented directly by the examiner would produce more responses than the same sentences presented via a tape recorder. METHODS Patients Our sample consisted of eight aphasic subjects with unilateral vascular lesions on the left hemisphere, as documented by clinical history, examination, and laboratory studies. They ranged in age from 38 to 77. All had at least a high-school education. Patients were selected on the basis of an observable severe comprehension disorder. A preliminary screening test, consisting of IO commands and questions (e.g., “Touch my left elbow,” “Does a board of wood float on water?” etc.) was administered to patients, and only those who failed 7 or more of the items were included in the study. Additional criteria for selection were that the patient not be too sick to be tested, and that he be able or willing to make at least some attempt to respond (verbally or otherwise) during the screening test. Of all patients who were considered for testing, five were eliminated because they passed more than three items of the screening test, two were eliminated because of total lack of response (verbal or other), and one was eliminated because he expressed his desire to withdraw after the procedure had been started (signaling that he was tired). Age, sex, and diagnosis of the eight selected patients are shown in Table I. Six had global aphasia with very little verbal output, either TABLE BACKGROUND
Patient’s no.
Age 72 38 46 55 74 55 59 72
a Maximum
I
INFORMATION AND NUMBEROF CORRECTLY ITEMS FOR EACH PATIENT
score = 120.
Sex
PERFORMED
Diagnosis
Total correct itemsa
Global Wernicke Global Global Global Wernicke Global Global
5 72 39 27 18 13 64 21
166
BOLLER
ET AL.
spontaneous or on repetition; one patient (No. 6) was a severe Wernicke’s aphasic with fluent verbal jargon, very little communicative ability, and grossly impaired ability to repeat; and one patient (No. 2) was a moderately severe Wernicke’s aphasic with fluent jargon, fair ability to communicate, and repetition in keeping with spontaneous output.
Test Our test battery consisted of 60 sentences, IO of which were judged to have “high emotional” content and 20 “low emotional” content, while 30 were intended as “neutral.” The “emotional load” of the sentences was determined as follows: The authors, independently, chose about 30 sentences each which they arbitrarily felt might be considered emotionally loaded. Of these, 50 sentences were primarily selected. Together with matched neutral sentences (see below), these were given to five persons in frequent contact with aphasics (speech therapists, nurses, etc.) who were asked to independently classify the utterances as “emotional” (i.e., meant to have an emotional impact on patients) or “neutral” (meant to have no emotional impact). Thirty sentences were finally selected as “emotional”; they consisted of IO commands, IO questions to be asked with “yes” or “no,” and IO questions requesting information. Of the 30 emotional items, IO were considered “high emotional” (i.e., expected to have a strong emotional impact on patients). This group included such items as” “Show me how you shoot a gun at someone.” “Do you want some whisky?” “Are you going to a nursing home?” etc. The 20 other emotional items were considered “low emotional” (i.e., expected to elicit a milder emotional reaction). Items in this group included, for example, “Do you have a happy family?” “ Show me how you drink beer.” “What would you do if you went home?” An effort was made to select items which would not be offensive to patients if understood. Each “emotional” sentence was matched with a “neutral” sentence, approximately similar in number of syllables, syntactic transformations, and word frequency. The 60 sentences were presented in a predetermined randomized order.
Procedure Each patient was given the series of 60 items by one of two modes of presentation: In the first mode (“voice”), the examiner read the sentences while sitting in front of the patient, avoiding gestures, changes in facial expression, and emotional vocal intonation. In the second mode (“tape”), the same sentences previously recorded by the same examiner were given to the patient via a tape recorder. The two modes were administered to each patient in two separate sessions (not on the same day and usually on 2 consecutive days) in counterbalanced order, so that four patients received “voice” first, while four patients received “tape” first.
Scoring In an effort to secure as objective a judgment of a patient’s performance as possible, two independent judges recorded and scored responses. One judge (judge 1, unmasked) presented the items either by speaking or by activating the tape recorder. While the item was presented, judge I also activated a generator which fed white noise via headphones into the ears of judge 2 (masked), who thus recorded the patients’ response to each item without knowledge of its form or content. The judges then scored each patient’s responses according to three criteria: (1) Whether the patient’s response was correct or incorrect. (2) Whether the patient’s resppnse was “appropriate” even if incorrect, following criteria detailed in previous research (Boiler and Green, 1972). For example, if a patient responded to the item “Show me how you shoot a gun at someone” with a gesture of any kind, his performance was considered appropriate; the same pertained to a “yes” or “no” expressed either verbally or by head shaking for the item “Are you an American?” and to any kind of verbal
AUDITORY
COMPREHENSION
167
response other than “yes” or “no” (including jargon or a clear-cut attempt to speak) to an information question, such as “What is your family name?” A performance was considered appropriate only if it did not appear to be a fixed stereotyped response indiscriminately given in response to a series of items. (3) Finally, judges scored each response for “change in general behavior.” Such changes could range from gross emotional alterations (a burst of laughter or crying) to withdrawing from the table and resting back in the chair. The response was considered to be a “change in general behavior” only if it was in clear contrast to the response generally given to other items. For each of these criteria, judges would score either 1 (indicating that the response was correct, appropriate, or constituted a change in general behavior) or 0 (indicating that the response was incorrect, inapproprate, or did not represent a change in general behavior). Every correct response was, of course, also appropriate but not vice versa. Thus, for each item the judges’ scores could range from 0 to 3. The masked judge scored his judgment on patients’ changes in general behavior without knowledge of the content of the item that had been presented to the patient. For scoring of “correct” and “appropriate” responses, however, no meaningful judgment was possible without knowledge of the content of the item. For these two criteria, the score ofjudge 2 was based on notations that had been made without knowledge of the item content, but interpretation and scoring of these notations were made with full knowledge of the content of the item.
RESULTS Table 1 shows the total number of correct items scored by each patient. The “total correct items” column in Table 1 has a maximum score of 120 (60 items repeated twice, once by “voice,” once by “tape”). As can be seen, patient 2, although she had failed 8 of the 10 screening items, had a fair amount of auditory comprehension, which can be inferred from the fact that she responded correctly to more than half the items (72/120). Patient 7 also understood correctly more than half (641120). All other patients responded correctly to less than one-third of the items. Figure 1 shows the results for the 10 “high emotional” items and their “neutral” counterparts. Each column represents the mean sum of the scores given by each judge. Figure 2 shows the results for all 60 items, i.e., the 10 “high emotional” and the 20 “low emotional” pooled under the “emotional” label, and their 30 “neutral” counterparts. In each figure, the scores of the two judges, the mode of presentation, and the emotional content of the items have been presented separately. In order to allow direct comparison of the ordinates, the scores shown in Figs. 1 and 2 were converted into percentages of the maximum theoretical score: 30 for the 10 “high emotional” (Fig. 1) and 90 for “high emotional” and “low emotional” combined (Fig. 2). The analysis, however, was carried out on the absolute scores. Tables 2 and 3 show the results of the analysis of variance (ANOVA) carried out for the data presented in Fig. 1 and Fig. 2, respectively. For both ANOVAs, none of the interactions were significant. There was a significant difference in effect of sentence content when the 10 “high emotional” items were analyzed separately (Fig. 1 and Table 2),
168
BOLLER
0
Unmasked
Masked
VOICE
ET AL.
Unmasked
Masked
TAPE
FIG. 1. Sum of the scores given by each judge for each mode of presentation (voice/ tape) and emotional content of the 10 “high emotional” items and 10 matched “neutral” sentences. Unmasked judge, I; masked judge, 2.
but this difference was no longer significant when the “high emotional“ and “low emotional” items were pooled before being compared to their “neutral”counterparts (Fig. 2 and Table 3). Analysis of the mode of presentation showed that when only the 10 “high emotional” and “neutral” counterparts were analyzed (Fig. 1 and Table 2), the difference between voice and tape was barely significant for the unmasked judge and fell short of significance for the masked judge. When all items were compared, however (Fig. 2 and Table 3), the results of the ANOVA showed that items read directly by the examiner (“voice”) elicited a significantly greater number of responses than did the same item presented by a tape recorder. Results noted in Figs. 1 and 2 suggest that the unmasked judge scored a higher number of responses than the masked judge. This number was found to be highly significant in an analysis carried out for all items (p < .007).
0
UIIt?Wkd
VOICE
Markad
Unmarkad
Matiad
TAPE
FIG. 2. Sum of the scores given by each judge to 30 “emotional” “neutral” sentences.
items and 30 matched
AUDITORY
ANOVA
169
COMPREHENSION
TABLE 2 FORTHE~O“MOSTEMOTIONAL"ITEMSAND “NEUTRAL" UTTERANCES
10 MATCHED
Judge
F
P
Content (emotional/neutral):
1 (Unmasked) 2 (Masked)
7.55 16.55
.029 ,007
Presentation (voice/tape):
1 (Unmasked) 2 (Masked)
5.67 5.00
,049 .067
Effect of
We also analyzed the scores given for each criterion as correct, appropriate, or behavioral. Perhaps because of the small number involved in each cell, few statistically significant results emerged. The emotional content of the sentences significantly increased the number of “behavioral” changes indicated by the unmasked judge. The other two criteria for the same judge and all criteria for the masked judge were unaffected by the content of the items. For mode of presentation the voice presentation increased the number of “behavioral” changes recorded by the unmasked judge and both the number of changes in general behavior and correct responses recorded by the masked judge. A similar analysis carried out for the 10 “high emotional” items showed that those sentences with emotional content produced a greater number of correct responses according to both judges and also produced a greater number of “behavioral” changes according to the unmasked judge. For the mode of presentation, a greater number of changes in general behavior following voice presentation were scored by the unmasked judge. The type of stimulus sentence (Yes/No questions, Information questions, Commands) was a highly significant factor in the number of responses elicited in our sample (p < .OOl). Of the three scoring criteria, it was the number of correct responses which was significantly affected. The greatest number of correct responses was produced by Yes/No questions.
ANOVA Effect of
TABLE 3 FOR ALL ITEMS Judge
F
P
Content (emotional/neutral):
1 (Unmasked) 2 (Masked)
2.67 3.81
,146 .099
Presentation (voice/tape):
1 (Unmasked) 2 (Masked)
6.39 6.07
.039 .049
170
BOLLER
ET AL.
DISCUSSION
These results suggest that both the content of sentences and the mode of presentation play a significant role in aphasics’ responses. The 10 “high emotional” items produced a greater number of responses when our three judging criteria (correct, appropriate, changes in general behavior) were combined and also produced a significantly greater number of correct responses. Furthermore, the difference in number of elicited responses decreased below the significance level when “high emotional” items were pooled with items expected by independent judges to have only milder emotional impact. It has long been known (Baillarger, 1865; Jackson, 1874; Goldstein, 1948) that there often is a marked discrepancy between emotional and nonemotional language in aphasics. Emotional utterances such as swearing and expressions of self-pity are often heard in aphasics and are sometimes the only verbal responses available to them. Moreover, it is a common clinical experience that in emotionally loaded circumstances aphasics sometimes speak better than ordinarily. For example, an occasional global aphasic with very reduced and stereotyped output may on the occasion of a visit by his family be heard saying “Mother, how are you?’ ’ and other appropriate statements. Although it was reasonable to expect a similar discrepancy on the receptive side, very little research had been carried out to corroborate such a prediction. Wechsler (1973) demonstrated an effect of this type when he showed that the ability of brain-damaged patients to remember a story was influenced by its emotional content. Kleinsmith and Kaplan (1964) showed that normal subjects’ learning of paired associates is influenced by high or low arousal at the time of learning. In their experiment, recall of material learned under low arousal was initially better than that of material learned under high arousal, but after a long interval (a week) the positions were reversed and the material learned under high arousal was recalled better than that learned under low arousal. The finding in the present study that emotional content of sentences increased responsiveness provides support for the prediction that emotional arousal has an impact on the reception as well as the expression of language in aphasics. The results of our experiments show that when aphasic subjects hear sentences spoken directly by the examiner, they produce a significantly greater number of responses than when the same items spoken by the same examiner originate from a tape recorder. This effect was greater when all items were analyzed than when only those 10 classified as “high emotional” were considered. This may be due to the fact that there were fewer items in the latter case. The importance of the mode of presentation was suggested in previous research (Green & Boller, 1974) and is
AUDITORY
COMPREHENSION
171
confirmed here. The effect of the mode of presentation is not likely to be due to a difference in voice quality and noise level between the direct voice and the tape recorder. In an earlier report, we noted the tendency of some aphasics to repeat items presented through the tape recorder rather than to respond to them. In addition, when items were presented by tape recorder, there was no tendency to ask, by voice or mimicry, for a repetition, which would indicate that the item had been poorly perceived. The dominant behavior in response to the tape recorder tended to be a total lack of response rather than an erroneous response. The examiner who read the items has extensive experience in testing patients and avoided providing cues by gesture or voice intonation. Moreover, the lack of significant interaction between mode of presentation and emotional content made it unlikely that gestural or facial cues facilitated patients* comprehension of the items. The unmasked judge gave significantly higher scores than did the masked judge. This could perhaps be due to a bias by which the examiner who knew what question had been asked tended to “over-interpret” the aphasics’ response. It is interesting, however, to see how in most cases the range of the difference between scores for emotional items and neutral ones tended to remain the same in both judges (cf. Figs. 1 and 2). The examiner who knew the item may have detected in the aphasics’ response elements that escaped the judge, who did not know what had been said and therefore did not know what to look for. Two patients gave a correct response to more than half the test items (Table I), despite having failed more than 7 out of 10 items in the screening test. Scoring in the screening test was quite generous: For example, if, in response to “Tear the paper into three parts” the patient took the paper but failed to cut it into exactly three parts, he was given the benefit of the doubt and got a correct score. The reasons these two patients responded correctly to a greater number of items in the actual test than in the screening test may be that the screening items were more difficult or that patients were unable to establish the appropriate response set for the screening test. On the basis of the results of previous research, Green and Boiler (1974) postulated a model for comprehension made of separate (but not necessarily successive) stages: Languages must be recognized as such; it must be distinguished from nonverbal noises; a particular language is identified as one that the patient is familiar with and can understand. The type of utterance is also differentiated (Is it a command? a question?). These stages of comprehension appear to be available even to some of the most severe aphasics. Aphasic impairment appears to hamper a final (and of course essential) step in comprehension: What is the exact meaning of what I heard? The results of our study suggest that an additional factor, the actual content of sentences, influences the response to an auditory
172
BOLLER
ET AL.
stimulus. Emotional items may improve the aphasics’ ability for phonemic and semantic decoding. Alternatively, the content of the item may influence the patient’s decision to respond or not to respond to a given stimulus. APPENDIX The following is a list of the actual stimuli used in the experiment. number of parentheses indicates their actual order of presentation. “High
Emotional”
Items and Matched
“Neutral”
Show me how you shoot a gun at someone. Show me how you talk on the phone. (13)
Items (3)
Do you hate your doctor? (7) Do you like your roommate? (16) Say “shit.” Say “shirt.”
(11) (53)
Do you want some whiskey? (19) Do you want some water? (51) Are you going to a nursing home? (28) Are you going to see a movie? (60) Will you ever get better? (31) Will you get a notebook? (41) Do you wet your bed? (33) Do you ever get hungry? (29) Show me which side of your body is weak. (43) Show me which side of the room has a door. (55) Are you an alcoholic? (56) Are you an American? (42) Do you want to go home? (59) Do you want to drink tea? (14) “LOW Emotional” Items and Matched “Neutral” Items How do you like to be in the hospital? (1) How do you like to be on this floor? (6)
The
AUDITORY
COMPREHENSION
Tell me when you got sick. (9) Tell me which floor we are on. (54) How do you feel? (10) How do you whistle? (52) There is a fire. Yell “fire.” Here is a pen. Say “pen.”
(12) (39)
What would you like to do now? (15) What would you like to see now? (49) What would you do if you won a million dollars? (17) What would you do if you had a red notebook? (23) Show me how you kiss. (20) Show me how you smile. (8) Who visited you last? (21) Who takes your blood pressure? (40) Are your pants wet or dry? (25) Is your room big or small? (34) What is your sainted mother’s name? (35) What is your family name? (4) Show me how you hug a baby. (36) Show me how you brush your teeth. (24) Hit me with your right hand. (37) Touch me with your left hand. (38) Show me how you kick a dog. (44) Show me how you kick a ball. (18) Does your family visit you? (45) Does your milk taste good? (2) Do you have a happy family? (46) Do you have a nice room? (26) Show me how you drink beer. (47) Show me how you drink milk. (27)
173
174
BOLLER
ET AL.
What would you do if you went home? (48) What would you do if you had a book? (32) Is your mother black? (to a white patient) or Is your mother white? (to a black patient) (50) Is the sky blue? (5) Show me how you cry. (57) Show me how you write. (22) How long have you been in the hospital? (58) How long have you lived in your town? (30) REFERENCES Baillarger, F. 1865. Sur la fact&e du langage articult. Bulletin Mkdecine,
30, 816-832,
de I’Acadkmie
lmptriale
de
840-853.
Blumstein, S. E., Baker, E., & Goodglass, H. 1977. Phonological factors in auditory comprehension in aphasia. Neuropsychologia, 15, 19-30. Boiler, F., & Green, E. 1972. Comprehension in severe aphasics. Cortex, 8, 382-394. Boiler, F., Kim, Y., & Mack, J. L. 1977. Auditory comprehension in aphasia. In H. Whitaker & H. A. Whitaker (Eds.), Studies in neurolinguistics. New York: Academic Press. Pp. l-63. Bransford, J. D., & Johnson, M. K. 1973. Considerations of some problems of comprehension. In W. G. Chase (Ed.), Visual information processing. New York: Academic Press. Gardner, H., Albert, M. L., & Weintraub, S. 1975. Comprehending a word: The influence of speed and redundancy on auditory comprehension in aphasia. Cortex, 11, 155-162. Goldstein, K. 1948. Language and language disturbances. New York: Grune & Stratton. Green, E., & Boiler, F. 1974. Features of auditory comprehension in severely impaired aphasics. Cortex, 10, 133-145. Jackson, H. 1874. On the nature of the duality of the brain. Medical Press Circular, 1,19,41, 65. Kleinsmith, L. S., & Kaplan, S. 1964. Paired associate learning as a function of arousal and interpolated interval. Journal of Experimental Psychology, 65, 190-193. Lebrun, Y. In press. Aspects of aphasia. In Y. Lebrun & R. Hoops (Eds.), Problems of aphasia. Amsterdam: Swets & Zeitlinger. Naeser, M. A. 1976. Untitled paper presented to the symposium: Brain and Language 9th Winter Conference on Brain Research. Summaries ofsymposia. UCLA, Los Angeles, Brain Information Service/BRI Publications Office, BIS Conference Report, No. 44. Pp. 50-55. Pizzamiglio, L., & Appicciafuoco, A. 1971. Semantic comprehension in aphasia. Journal of Communicative
Disorders,
3, 280-288.
Stachowiak, J., Huber, W., Poeck, K., & Kerschensteiner, M. 1977. Text comprehension in aphasia. Brain and Language, 4, 177-195. Wechsler, A. F. 1973. The effect of organic brain disease on recall of emotionally charged versus neutral narrative texts. Neurology, 23, 130-135.
AND
LANGUAGE
Paralinguistic
7,
(1979)
164-li’;
Aspects of Auditory in Aphasia
Comprehension
BOLLER, MONROE COLE, P. BART VRTUNSKI, MARIAN PATTERSON. AND YOUNGJAI KIM
FRANGOIS
Cleveland
Veterans
Administration
Hospital
Eight severe aphasics were given sentences with either emotional or neutral content, presented once directly by the examiner and once via a tape recorder. Sentences with emotional content produced a greater number of responses than their neutral counterparts. Sentences spoken by the exaininer also produced a significantly greater number of responses than the same items originating from a tape recorder. These results confirm the view that elements not related to the linguistic aspects of a message (and therefore referred to as paralinguistic) play a significant role in auditory comprehension,
There is increasing interest in trying to understand better the nature of the comprehension impairment that exists in virtually every aphasic patient. Greatest attention has been paid thus far to the role of linguistic factors, i.e., phonemic (Blumstein, Baker, & Goodglass, 1977; Naeser, 1976), syntactic, and semantic (Pizzamiglio & Appicciafuoco, 1971); in auditory comprehension. It has also been shown, however, that elements not related to the linguistic aspect of the message, and therefore referred to as “paralinguistic” (Boller, Kim, & Mack, 1977), play a role in auditory comprehension. Goldstein (1948), for example, stressed that patients who often cannot perform correctly in a test situation may be able to perform the same task in daily situations. Other studies have examined the importance of such factors as context (Bransford & Johnson, 1973; Stachowiak, Huber, Poeck, & Kerschensteiner, 1977; Lebrun, in press), speed (Gardner, Albert, & Weintraub, 1975), mode of presentation (Green & Boller, 1974), and emotional content of utterances (Wechsler, 1973). These studies have established the importance of paralinguistic factors, even though the precise role they play in the auditory comprehension of aphasics remains to be more clearly defined. It has recently been stressed (Boller & Green, 1972; Green & Boller, 1974) that in order to study the comprehension of aphasics, especially those with the most severe impairment, one must pay attention to more Requests for reprints should be sent to: Dr. Franqois Boller, Neurobehavior land VA Hospital, 10701 East Boulevard, Cleveland, OH 44106. 164 0093-934x/79/020164-1 1$02.00/O Copyright All rights
($I 1979 by Academic Press, Inc. of reproduction in any form reserved.
Unit, Cleve-
AUDITORY
165
COMPREHENSION
than whether their response (verbal or gestural) is correct. Other aspects of the patient’s performance, such as a puzzled look or a burst of laughter, or a performance which, although incorrect, is related to the question asked or the command given, may be just as important in determining how much has been understood. In the present study, we wanted to evaluate the role of emotional content and mode of presentation of a series of sentences on the comprehension of severe aphasics. We hypothesized that if content of the sentences affected the way in which patients responded, there would be a greater number of responses to sentences with emotional content than to neutral sentences even if the responses might not be correct. We also hypothesized that sentences presented directly by the examiner would produce more responses than the same sentences presented via a tape recorder. METHODS Patients Our sample consisted of eight aphasic subjects with unilateral vascular lesions on the left hemisphere, as documented by clinical history, examination, and laboratory studies. They ranged in age from 38 to 77. All had at least a high-school education. Patients were selected on the basis of an observable severe comprehension disorder. A preliminary screening test, consisting of IO commands and questions (e.g., “Touch my left elbow,” “Does a board of wood float on water?” etc.) was administered to patients, and only those who failed 7 or more of the items were included in the study. Additional criteria for selection were that the patient not be too sick to be tested, and that he be able or willing to make at least some attempt to respond (verbally or otherwise) during the screening test. Of all patients who were considered for testing, five were eliminated because they passed more than three items of the screening test, two were eliminated because of total lack of response (verbal or other), and one was eliminated because he expressed his desire to withdraw after the procedure had been started (signaling that he was tired). Age, sex, and diagnosis of the eight selected patients are shown in Table I. Six had global aphasia with very little verbal output, either TABLE BACKGROUND
Patient’s no.
Age 72 38 46 55 74 55 59 72
a Maximum
I
INFORMATION AND NUMBEROF CORRECTLY ITEMS FOR EACH PATIENT
score = 120.
Sex
PERFORMED
Diagnosis
Total correct itemsa
Global Wernicke Global Global Global Wernicke Global Global
5 72 39 27 18 13 64 21
166
BOLLER
ET AL.
spontaneous or on repetition; one patient (No. 6) was a severe Wernicke’s aphasic with fluent verbal jargon, very little communicative ability, and grossly impaired ability to repeat; and one patient (No. 2) was a moderately severe Wernicke’s aphasic with fluent jargon, fair ability to communicate, and repetition in keeping with spontaneous output.
Test Our test battery consisted of 60 sentences, IO of which were judged to have “high emotional” content and 20 “low emotional” content, while 30 were intended as “neutral.” The “emotional load” of the sentences was determined as follows: The authors, independently, chose about 30 sentences each which they arbitrarily felt might be considered emotionally loaded. Of these, 50 sentences were primarily selected. Together with matched neutral sentences (see below), these were given to five persons in frequent contact with aphasics (speech therapists, nurses, etc.) who were asked to independently classify the utterances as “emotional” (i.e., meant to have an emotional impact on patients) or “neutral” (meant to have no emotional impact). Thirty sentences were finally selected as “emotional”; they consisted of IO commands, IO questions to be asked with “yes” or “no,” and IO questions requesting information. Of the 30 emotional items, IO were considered “high emotional” (i.e., expected to have a strong emotional impact on patients). This group included such items as” “Show me how you shoot a gun at someone.” “Do you want some whisky?” “Are you going to a nursing home?” etc. The 20 other emotional items were considered “low emotional” (i.e., expected to elicit a milder emotional reaction). Items in this group included, for example, “Do you have a happy family?” “ Show me how you drink beer.” “What would you do if you went home?” An effort was made to select items which would not be offensive to patients if understood. Each “emotional” sentence was matched with a “neutral” sentence, approximately similar in number of syllables, syntactic transformations, and word frequency. The 60 sentences were presented in a predetermined randomized order.
Procedure Each patient was given the series of 60 items by one of two modes of presentation: In the first mode (“voice”), the examiner read the sentences while sitting in front of the patient, avoiding gestures, changes in facial expression, and emotional vocal intonation. In the second mode (“tape”), the same sentences previously recorded by the same examiner were given to the patient via a tape recorder. The two modes were administered to each patient in two separate sessions (not on the same day and usually on 2 consecutive days) in counterbalanced order, so that four patients received “voice” first, while four patients received “tape” first.
Scoring In an effort to secure as objective a judgment of a patient’s performance as possible, two independent judges recorded and scored responses. One judge (judge 1, unmasked) presented the items either by speaking or by activating the tape recorder. While the item was presented, judge I also activated a generator which fed white noise via headphones into the ears of judge 2 (masked), who thus recorded the patients’ response to each item without knowledge of its form or content. The judges then scored each patient’s responses according to three criteria: (1) Whether the patient’s response was correct or incorrect. (2) Whether the patient’s resppnse was “appropriate” even if incorrect, following criteria detailed in previous research (Boiler and Green, 1972). For example, if a patient responded to the item “Show me how you shoot a gun at someone” with a gesture of any kind, his performance was considered appropriate; the same pertained to a “yes” or “no” expressed either verbally or by head shaking for the item “Are you an American?” and to any kind of verbal
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response other than “yes” or “no” (including jargon or a clear-cut attempt to speak) to an information question, such as “What is your family name?” A performance was considered appropriate only if it did not appear to be a fixed stereotyped response indiscriminately given in response to a series of items. (3) Finally, judges scored each response for “change in general behavior.” Such changes could range from gross emotional alterations (a burst of laughter or crying) to withdrawing from the table and resting back in the chair. The response was considered to be a “change in general behavior” only if it was in clear contrast to the response generally given to other items. For each of these criteria, judges would score either 1 (indicating that the response was correct, appropriate, or constituted a change in general behavior) or 0 (indicating that the response was incorrect, inapproprate, or did not represent a change in general behavior). Every correct response was, of course, also appropriate but not vice versa. Thus, for each item the judges’ scores could range from 0 to 3. The masked judge scored his judgment on patients’ changes in general behavior without knowledge of the content of the item that had been presented to the patient. For scoring of “correct” and “appropriate” responses, however, no meaningful judgment was possible without knowledge of the content of the item. For these two criteria, the score ofjudge 2 was based on notations that had been made without knowledge of the item content, but interpretation and scoring of these notations were made with full knowledge of the content of the item.
RESULTS Table 1 shows the total number of correct items scored by each patient. The “total correct items” column in Table 1 has a maximum score of 120 (60 items repeated twice, once by “voice,” once by “tape”). As can be seen, patient 2, although she had failed 8 of the 10 screening items, had a fair amount of auditory comprehension, which can be inferred from the fact that she responded correctly to more than half the items (72/120). Patient 7 also understood correctly more than half (641120). All other patients responded correctly to less than one-third of the items. Figure 1 shows the results for the 10 “high emotional” items and their “neutral” counterparts. Each column represents the mean sum of the scores given by each judge. Figure 2 shows the results for all 60 items, i.e., the 10 “high emotional” and the 20 “low emotional” pooled under the “emotional” label, and their 30 “neutral” counterparts. In each figure, the scores of the two judges, the mode of presentation, and the emotional content of the items have been presented separately. In order to allow direct comparison of the ordinates, the scores shown in Figs. 1 and 2 were converted into percentages of the maximum theoretical score: 30 for the 10 “high emotional” (Fig. 1) and 90 for “high emotional” and “low emotional” combined (Fig. 2). The analysis, however, was carried out on the absolute scores. Tables 2 and 3 show the results of the analysis of variance (ANOVA) carried out for the data presented in Fig. 1 and Fig. 2, respectively. For both ANOVAs, none of the interactions were significant. There was a significant difference in effect of sentence content when the 10 “high emotional” items were analyzed separately (Fig. 1 and Table 2),
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Unmasked
Masked
VOICE
ET AL.
Unmasked
Masked
TAPE
FIG. 1. Sum of the scores given by each judge for each mode of presentation (voice/ tape) and emotional content of the 10 “high emotional” items and 10 matched “neutral” sentences. Unmasked judge, I; masked judge, 2.
but this difference was no longer significant when the “high emotional“ and “low emotional” items were pooled before being compared to their “neutral”counterparts (Fig. 2 and Table 3). Analysis of the mode of presentation showed that when only the 10 “high emotional” and “neutral” counterparts were analyzed (Fig. 1 and Table 2), the difference between voice and tape was barely significant for the unmasked judge and fell short of significance for the masked judge. When all items were compared, however (Fig. 2 and Table 3), the results of the ANOVA showed that items read directly by the examiner (“voice”) elicited a significantly greater number of responses than did the same item presented by a tape recorder. Results noted in Figs. 1 and 2 suggest that the unmasked judge scored a higher number of responses than the masked judge. This number was found to be highly significant in an analysis carried out for all items (p < .007).
0
UIIt?Wkd
VOICE
Markad
Unmarkad
Matiad
TAPE
FIG. 2. Sum of the scores given by each judge to 30 “emotional” “neutral” sentences.
items and 30 matched
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TABLE 2 FORTHE~O“MOSTEMOTIONAL"ITEMSAND “NEUTRAL" UTTERANCES
10 MATCHED
Judge
F
P
Content (emotional/neutral):
1 (Unmasked) 2 (Masked)
7.55 16.55
.029 ,007
Presentation (voice/tape):
1 (Unmasked) 2 (Masked)
5.67 5.00
,049 .067
Effect of
We also analyzed the scores given for each criterion as correct, appropriate, or behavioral. Perhaps because of the small number involved in each cell, few statistically significant results emerged. The emotional content of the sentences significantly increased the number of “behavioral” changes indicated by the unmasked judge. The other two criteria for the same judge and all criteria for the masked judge were unaffected by the content of the items. For mode of presentation the voice presentation increased the number of “behavioral” changes recorded by the unmasked judge and both the number of changes in general behavior and correct responses recorded by the masked judge. A similar analysis carried out for the 10 “high emotional” items showed that those sentences with emotional content produced a greater number of correct responses according to both judges and also produced a greater number of “behavioral” changes according to the unmasked judge. For the mode of presentation, a greater number of changes in general behavior following voice presentation were scored by the unmasked judge. The type of stimulus sentence (Yes/No questions, Information questions, Commands) was a highly significant factor in the number of responses elicited in our sample (p < .OOl). Of the three scoring criteria, it was the number of correct responses which was significantly affected. The greatest number of correct responses was produced by Yes/No questions.
ANOVA Effect of
TABLE 3 FOR ALL ITEMS Judge
F
P
Content (emotional/neutral):
1 (Unmasked) 2 (Masked)
2.67 3.81
,146 .099
Presentation (voice/tape):
1 (Unmasked) 2 (Masked)
6.39 6.07
.039 .049
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DISCUSSION
These results suggest that both the content of sentences and the mode of presentation play a significant role in aphasics’ responses. The 10 “high emotional” items produced a greater number of responses when our three judging criteria (correct, appropriate, changes in general behavior) were combined and also produced a significantly greater number of correct responses. Furthermore, the difference in number of elicited responses decreased below the significance level when “high emotional” items were pooled with items expected by independent judges to have only milder emotional impact. It has long been known (Baillarger, 1865; Jackson, 1874; Goldstein, 1948) that there often is a marked discrepancy between emotional and nonemotional language in aphasics. Emotional utterances such as swearing and expressions of self-pity are often heard in aphasics and are sometimes the only verbal responses available to them. Moreover, it is a common clinical experience that in emotionally loaded circumstances aphasics sometimes speak better than ordinarily. For example, an occasional global aphasic with very reduced and stereotyped output may on the occasion of a visit by his family be heard saying “Mother, how are you?’ ’ and other appropriate statements. Although it was reasonable to expect a similar discrepancy on the receptive side, very little research had been carried out to corroborate such a prediction. Wechsler (1973) demonstrated an effect of this type when he showed that the ability of brain-damaged patients to remember a story was influenced by its emotional content. Kleinsmith and Kaplan (1964) showed that normal subjects’ learning of paired associates is influenced by high or low arousal at the time of learning. In their experiment, recall of material learned under low arousal was initially better than that of material learned under high arousal, but after a long interval (a week) the positions were reversed and the material learned under high arousal was recalled better than that learned under low arousal. The finding in the present study that emotional content of sentences increased responsiveness provides support for the prediction that emotional arousal has an impact on the reception as well as the expression of language in aphasics. The results of our experiments show that when aphasic subjects hear sentences spoken directly by the examiner, they produce a significantly greater number of responses than when the same items spoken by the same examiner originate from a tape recorder. This effect was greater when all items were analyzed than when only those 10 classified as “high emotional” were considered. This may be due to the fact that there were fewer items in the latter case. The importance of the mode of presentation was suggested in previous research (Green & Boller, 1974) and is
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confirmed here. The effect of the mode of presentation is not likely to be due to a difference in voice quality and noise level between the direct voice and the tape recorder. In an earlier report, we noted the tendency of some aphasics to repeat items presented through the tape recorder rather than to respond to them. In addition, when items were presented by tape recorder, there was no tendency to ask, by voice or mimicry, for a repetition, which would indicate that the item had been poorly perceived. The dominant behavior in response to the tape recorder tended to be a total lack of response rather than an erroneous response. The examiner who read the items has extensive experience in testing patients and avoided providing cues by gesture or voice intonation. Moreover, the lack of significant interaction between mode of presentation and emotional content made it unlikely that gestural or facial cues facilitated patients* comprehension of the items. The unmasked judge gave significantly higher scores than did the masked judge. This could perhaps be due to a bias by which the examiner who knew what question had been asked tended to “over-interpret” the aphasics’ response. It is interesting, however, to see how in most cases the range of the difference between scores for emotional items and neutral ones tended to remain the same in both judges (cf. Figs. 1 and 2). The examiner who knew the item may have detected in the aphasics’ response elements that escaped the judge, who did not know what had been said and therefore did not know what to look for. Two patients gave a correct response to more than half the test items (Table I), despite having failed more than 7 out of 10 items in the screening test. Scoring in the screening test was quite generous: For example, if, in response to “Tear the paper into three parts” the patient took the paper but failed to cut it into exactly three parts, he was given the benefit of the doubt and got a correct score. The reasons these two patients responded correctly to a greater number of items in the actual test than in the screening test may be that the screening items were more difficult or that patients were unable to establish the appropriate response set for the screening test. On the basis of the results of previous research, Green and Boiler (1974) postulated a model for comprehension made of separate (but not necessarily successive) stages: Languages must be recognized as such; it must be distinguished from nonverbal noises; a particular language is identified as one that the patient is familiar with and can understand. The type of utterance is also differentiated (Is it a command? a question?). These stages of comprehension appear to be available even to some of the most severe aphasics. Aphasic impairment appears to hamper a final (and of course essential) step in comprehension: What is the exact meaning of what I heard? The results of our study suggest that an additional factor, the actual content of sentences, influences the response to an auditory
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stimulus. Emotional items may improve the aphasics’ ability for phonemic and semantic decoding. Alternatively, the content of the item may influence the patient’s decision to respond or not to respond to a given stimulus. APPENDIX The following is a list of the actual stimuli used in the experiment. number of parentheses indicates their actual order of presentation. “High
Emotional”
Items and Matched
“Neutral”
Show me how you shoot a gun at someone. Show me how you talk on the phone. (13)
Items (3)
Do you hate your doctor? (7) Do you like your roommate? (16) Say “shit.” Say “shirt.”
(11) (53)
Do you want some whiskey? (19) Do you want some water? (51) Are you going to a nursing home? (28) Are you going to see a movie? (60) Will you ever get better? (31) Will you get a notebook? (41) Do you wet your bed? (33) Do you ever get hungry? (29) Show me which side of your body is weak. (43) Show me which side of the room has a door. (55) Are you an alcoholic? (56) Are you an American? (42) Do you want to go home? (59) Do you want to drink tea? (14) “LOW Emotional” Items and Matched “Neutral” Items How do you like to be in the hospital? (1) How do you like to be on this floor? (6)
The
AUDITORY
COMPREHENSION
Tell me when you got sick. (9) Tell me which floor we are on. (54) How do you feel? (10) How do you whistle? (52) There is a fire. Yell “fire.” Here is a pen. Say “pen.”
(12) (39)
What would you like to do now? (15) What would you like to see now? (49) What would you do if you won a million dollars? (17) What would you do if you had a red notebook? (23) Show me how you kiss. (20) Show me how you smile. (8) Who visited you last? (21) Who takes your blood pressure? (40) Are your pants wet or dry? (25) Is your room big or small? (34) What is your sainted mother’s name? (35) What is your family name? (4) Show me how you hug a baby. (36) Show me how you brush your teeth. (24) Hit me with your right hand. (37) Touch me with your left hand. (38) Show me how you kick a dog. (44) Show me how you kick a ball. (18) Does your family visit you? (45) Does your milk taste good? (2) Do you have a happy family? (46) Do you have a nice room? (26) Show me how you drink beer. (47) Show me how you drink milk. (27)
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What would you do if you went home? (48) What would you do if you had a book? (32) Is your mother black? (to a white patient) or Is your mother white? (to a black patient) (50) Is the sky blue? (5) Show me how you cry. (57) Show me how you write. (22) How long have you been in the hospital? (58) How long have you lived in your town? (30) REFERENCES Baillarger, F. 1865. Sur la fact&e du langage articult. Bulletin Mkdecine,
30, 816-832,
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Blumstein, S. E., Baker, E., & Goodglass, H. 1977. Phonological factors in auditory comprehension in aphasia. Neuropsychologia, 15, 19-30. Boiler, F., & Green, E. 1972. Comprehension in severe aphasics. Cortex, 8, 382-394. Boiler, F., Kim, Y., & Mack, J. L. 1977. Auditory comprehension in aphasia. In H. Whitaker & H. A. Whitaker (Eds.), Studies in neurolinguistics. New York: Academic Press. Pp. l-63. Bransford, J. D., & Johnson, M. K. 1973. Considerations of some problems of comprehension. In W. G. Chase (Ed.), Visual information processing. New York: Academic Press. Gardner, H., Albert, M. L., & Weintraub, S. 1975. Comprehending a word: The influence of speed and redundancy on auditory comprehension in aphasia. Cortex, 11, 155-162. Goldstein, K. 1948. Language and language disturbances. New York: Grune & Stratton. Green, E., & Boiler, F. 1974. Features of auditory comprehension in severely impaired aphasics. Cortex, 10, 133-145. Jackson, H. 1874. On the nature of the duality of the brain. Medical Press Circular, 1,19,41, 65. Kleinsmith, L. S., & Kaplan, S. 1964. Paired associate learning as a function of arousal and interpolated interval. Journal of Experimental Psychology, 65, 190-193. Lebrun, Y. In press. Aspects of aphasia. In Y. Lebrun & R. Hoops (Eds.), Problems of aphasia. Amsterdam: Swets & Zeitlinger. Naeser, M. A. 1976. Untitled paper presented to the symposium: Brain and Language 9th Winter Conference on Brain Research. Summaries ofsymposia. UCLA, Los Angeles, Brain Information Service/BRI Publications Office, BIS Conference Report, No. 44. Pp. 50-55. Pizzamiglio, L., & Appicciafuoco, A. 1971. Semantic comprehension in aphasia. Journal of Communicative
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Stachowiak, J., Huber, W., Poeck, K., & Kerschensteiner, M. 1977. Text comprehension in aphasia. Brain and Language, 4, 177-195. Wechsler, A. F. 1973. The effect of organic brain disease on recall of emotionally charged versus neutral narrative texts. Neurology, 23, 130-135.