BRAIN

AND

LANGUAGE

6, 192-211 (1978)

Recovery from Aphasia: Spontaneous Speech versus Language Comprehension RONALD S. PRINS, CATHERINE E. SNOW AND ERIN WAGENAAR University

of Amsterdam

Seventy-four aphasic patients, subdivided into four groups (fluent, mixed, nonfluent, and severely nonfluent), were tested three times in the course of 1 year to assess recovery of spontaneous speech and sentence comprehension. Although 12 of the 28 spontaneous speech variables employed showed significant time changes, some of these changes indicated improvement and others deterioration. There was no overall clinical improvement in spontaneous speech in any group. On the sentence comprehension tests, however, all four groups did show considerable, significant improvement. There were no qualitative or quantitative differences among the groups in the course of recovery, despite the fact that the groups differed in the severity of aphasia as well as on the fluency dimension. In certain patients there was also some improvement in spontaneous speech, but this did not in most cases correlate with an improvement in either fluency or sentence comprehension. Possible reasons why receptive abilities improved more than expressive abilities are discussed.

Recovery from aphasia is affected by many factors, including the etiology, locus, and extent of the lesion, the type and severity of aphasia, the time elapsed since its onset, and the age, educational level, and motivation of the patient (reviewed in Darley, 1972, 1975; Sarno, 1976). Not only is knowledge about precisely how these separate factors affect recovery inadequate, but there is no information about how they interact, especially in less clearcut cases where the relevant variables may take intermediate values. The difficulties inherent in predicting recovery are multiplied when attempting to assess the role of language therapy in supporting recovery. As Darley (1972, pp. 7-g) has pointed out, general statements about the effectiveness of aphasia therapy are almost certainly ill-advised. Rather The data were collected as part of a project organized by the Aphasia Foundation of The Netherlands, supported by a grant from the Praeventiefonds, The Hague. Some of the data have already appeared in preliminary reports on the research project Her herstelverloop van afasie (1976) and Nederlands Tijdschrift voor de Psychologie (1976, 31, 425-444). We are grateful to Marjo van Beek-Dieters and Mieke van de Sandt-Koenderman for their contribution to the research. Address reprint requests to R. S. Prins, Institute for General Linguistics, University of Amsterdam, Spuistraat 210, Amsterdam, The Netherlands. 0093-934X/78/0062-0192$02.00/0 Copyright AU risbts

Q 1578 by Academic Press, Inc. of reproduction in any form reserved.

192

RECOVERY

FROM APHASIA

193

than asking the question “Does therapy contribute to recovery from aphasia?“, one should ask what kind of therapy is effective for what type of patient, and when, how often, and for how long it should be given to maintain maximum effectiveness. A certain amount is known about the role of therapy and of the various factors mentioned above in affecting recovery. In general, young patients with a mild aphasia as a result of trauma seem to have a very good prognosis, especially if spontaneous recovery during the first week has been great and if therapy is started soon after the accident (Gloning, Trappl, Heis, & Quatember, 1976; Luria & Tsvetkova, personal communication; Vignolo, 1964). Patients older than about 40 who have contracted a serious aphasia as a result of a cerebrovascular accident (CVA) and who have passed the period of spontaneous recovery [l month according to Culton (1969); 2 months according to Vignolo (1964); 3 months according to Sarno & Levita (1971); 5 to 6 months according to Lenneberg (1967) and Luria (1970)] seem to have a very bad prognosis, although some of them may still benefit from therapy (Sands, Sat-no, & Shankweiler, 1969; Samo, Silverman, & Sands, 1970; Darley, 1975). Nonetheless, it is older CVA patients with severe aphasia who form the largest part of the aphasic population and for whom the question of the effectiveness of therapy is of the greatest importance. The imprecision of the statements about the factors affecting recovery is compounded by confusion in the statements about the form that recovery will take. There is some evidence that certain types of deficits recover better than others, although once again this evidence is both sparse and contradictory. Some authors suggest that expressive deficits recover better (Butfield & Zangwill, 1946; Godfrey & Douglass, 1959), whereas the general clinical impression is that receptive deficits improve more (Schreuder, 1973; Lebrun, 1976, p. 28) and this belief has been supported by the results of Vignolo (1964) and Leischner (1972, 1976).’ None of the studies which have assessed recovery has undertaken systematic analysis of recovery of spontaneous speech, which is without ’ The evidence that Leischner (1972,1976) presents is only indirect. From his dataabout the change of syndromes (“Syndromwandel”) in aphasia during the recovery period, it can, however, readily be deduced that receptive deficits tend to improve more than expressive ones. At the time of the first diagnosis, the two largest groups in his sample of 300 aphasics were total aphasia (n=95) and mixed aphasia (n=63), respectively, both groups being characterized by disorders in spontaneous speech and in language comprehension. At the end of the treatment period (at least 3 months), 17 patients with total and 34 with mixed aphasia were finally diagnosed as one of several varieties of motor and/or amnesic aphasia in which there is, according to Leischner, a disorder of spontaneous speech and/or word finding, but not of language comprehension. Thus it can be concluded that receptive disorders have a better prognosis than expressive ones, although we do not agree with Leischner that motor and amnesic types of aphasia have no comprehension difficulties whatsoever. No conclusion can be made from Leischner’s data about whether or not the expressive and/or receptive difficulties of patients of a certain (fixed) type tend to improve over time.

194

PRINS, SNOW, AND WAGENAAR

doubt the skill in which improvement contributes most to the patient’s own sense of recovery and to that of his family and friends. It is, thus, of considerable social relevance to be able to assess recovery, and thereby the role of the various factors which might affect recovery, for spontaneous speech separately from comprehension and other, nonspontaneous expressive abilities. Assessment of recovery in spontaneous speech ability becomes the more important with the recent tendency to replace the classical dichotomy of motor and sensory types of aphasia, based on a differential disruption of expressive and receptive skills, by a “new” distinction between fluent and nonfluent aphasia, based solely on spontaneous speech characteristics. Some recent studies which have dealt exclusively with spontaneous speech have shown that approximately 75% of the aphasic population can be classified as either nonfluent or fluent (Benson, 1967; Kerschensteiner, Poeck, & Brunner, 1972; Wagenaar, Snow, & Prins, 1975). The nonfluent patient can be characterized as speaking slowly and laboriously, in short utterances produced with poor articulation, melody, and syntax. The fluent patient shows the complementary picture, speaking at a normal or even excessive rate, without effort and with normal articulation, melody, and syntactic variety. In these cases the aphasia reveals itself in the presence of TABLE

I

AGE, SEX, EDUCATIONAL LEVEL, OCCUPATIONAL LEVEL, HOSPITALIZATION, AND DURATION AND FREQUENCY OF THERAPY IN THE PATIENT SAMPLE (n = 74) Age (years)

Mean Range

60.45 28-81

Sex

Female Male

39 45

Mean Range

2.5 l-7

Mean Range

2.6 o-7

Hospitalization

Yes No

32 42

Duration of therapy at first session (months)

Mean Range

10.96 o-99

Frequency of therapy (sessions per week)

Mean Range

3.14 o-7

Educational

level (l-7)”

Occupational

level (O-7)b

” According to the scale used by Verhage (1964). 1 = Elementary school only, 7 = university degree. * According to the scale established by the Dutch Federal Employment Bureau. 0 = Housewife, 4 = white-collar worker, 7 = professional.

RECOVERY

FROM APHASIA

195

literal or verbal paraphasias and in the use of many circumlocutions and words of indefinite reference. The explanatory power of the fluent-nonfluent distinction is further corroborated by the results of investigations which have shown that all aphasics, regardless of diagnostic type, show qualitatively similar comprehension difficulties (Goodglass, 1968; Orgass & Poeck, 1966; Parisi & Pizzamiglio, 1970; Poeck, Kerschensteiner, & Hartje, 1972; Shewan & Canter, 1971). However, these studies have relied exclusively on the Token Test or on tests of a few morphological or syntactical rules and thus have not exhaustively explored possible differences between subgroups of aphasics in the nature of their comprehension deficit. More differentiated analysis of the components of comprehension ability might well reveal interesting differences between subgroups and differences in the course of recovery for the different abilities. The purpose of the present paper is to compare recovery for the two major aspects of language ability, spontaneous speech and comprehension, in four groups of CVA patients which differed on the fluency dimension. Specially devised comprehension tests and an objective, quantified method for assessing spontaneous speech were used in evaluating recovery over the course of 1 year. Differences between the diagnostic groups in comprehension ability will also be discussed. METHOD Subjects Eighty-one CVA aphasics from 14 different treatment centers who could be tested three times in the course of 1 year were included in the study. These patients had all become aphasic at least 3 months prior to the beginning of the study, the aphasia being determined by diagnosis of the consulting neurologist and/or scores on the Token Test as standardized for Dutch (Van Dongen, Van Harskamp, Verhey-Stol, & Luteijn, 1974). Information concerning age, sex, educational level, premorbid occupation, hospitalization, and therapy histories of the patient group is given in Table 1. Data for 7 of the 8 1 patients are incomplete either for spontaneous speech or for comprehension. Another 20 patients could not actually be scored on spontaneous speech because they produced only a few words (mainly “yes” or “no”), incomprehensible muttering, or only verbal stereotypies. These patients will be referred to as the Severely Nonfluent (SNF) group. The 54 patients for whom complete data concerning spontaneous speech are available can be classified on the basis of their speech at session I as nonfluent (NF; n = 22), mixed (M; n = 17) or fluent (F;n = 15), using the double criterion of Speech Tempo and Mean Length of Utterance (MLU) proposed by Wagenaar et al. (1975). These three groups of patients differ significantly from one another on most aspects of spontaneous speech (see Wagenaar et al., 1975; also see below), and thus can be seen as distinct groups whose prognoses might well differ. It should be noted that our fluent group may not be directly comparable to the groups described as fluent by other researchers (Benson, 1967; Kerschensteiner et al., 1972; Goodglass & Kaplan, 1972), since in our group there were no typical cases of Wemicke’s aphasia, characterized by press of speech and many paraphasia errors. In addition, spontaneous speech was collected from 18 control subjects; 10 of these were CVA patients who had suffered right hemisphere damage, were not aphasic according to their

196

PRINS, SNOW, AND WAGENAAR

scores on the Token Test, and had no clinically apparent difficulties in their spontaneous speech. The other eight were family members of aphasic patients. Their speech was collected and analyzed in the same way as that of the aphasic patients (see the following). Since there were no significant differences between these two subgroups of controls, they will be treated as one group in the following.

Testing and Scoring Patients were tested individually three times at Cmonth intervals during the course of therapy on an extensive test battery designed to assess several aspects of psycholinguistic ability, e.g., phonological discrimination, word discrimination, confrontation naming, word fluency (animal naming), phrase repetition, sentence production, sentence comprehension, and spontaneous speech (see Her herstelverloop van ufasie, 1976). The results to be discussed below are derived from the last two subtests in this battery. Spontaneous speech. In the course of administration of the test battery, the test assistant occasionally presented a conversational topic to the patient in an informal way, and then recorded his spontaneous speech. Two minutes’ discussion of three such conversational topics provided the spontaneous speech corpus analyzed for each patient. The conversational topics were: (a) What do you spend your days doing? (b) tell me about the place you come from; and(c) how did your difficulties with talking come about? (or, for the control group, tell me something about your work/household). The test assistant was instructed to maintain a normal, informal conversational mood and to let the patient talk as much as possible without intervening. Transcriptions ofthe patients’ speech, made the same day by the test assistants in normal orthography, were used, together with the tapes, for analysis. The spontaneous speech was scored on 28 variables, selected by factor analysis from 45 variables which had been chosen on the basis of psycholinguistic relevance or earlier research results. A more complete description of the scoring procedure and of the motivation for choosing the variables is given in Wagenaar et al. (1975). The 28 variables are listed in Table 2, together with the details of how they were calculated. Three of the variables, Communicative Capacity, Melody, and Articulation, were subjective rating scales, with 1 indicating severe deficit and 7 normal ability in all cases. These rating scales are comparable to those used by Goodglass and Kaplan (1972); Communicative Capacity can be seen as a measure of the severity of the aphasia. Intejudge reliability ratings for these scales, calculated on a group of 101 patients (including the 81 reported on here), for the two out ofthree judges who disagreed maximally, were .93, .94, and .91, respectively (Pearson product-moment correlations, p < Xl01 in all cases). Sentence comprehension. Two tests of comprehension abilities were administered, a Morphosyntactic Comprehension Test (MCT) and an Ambiguity Comprehension Test (ACT). The MCT consisted of 60 items, 4 for each of the 15 morphological or syntactic structures being tested. Each item consisted of a sentence and two pictures. [For a similar test, see Parisi & Pizzamiglio (1970).] The 15 structures and example sentences are given in Table 3 and an example of the pictures in Fig. 1. The sentence was read aloud to the patient and he was asked to point to the picture that went with it. The sentences, which were all four to eight words long and contained no syntactic or semantic difficulties except for the structure tested, were presented in random order. The patient received one point for each item answered correctly. The maximum score was 60. The ACT included eight items, each consisting of one sentence and four pictures, two of which were accurately described by the sentence. Four ofthese sentences were ambiguous at the lexical level, e.g., in Dutch hijpakt de slang, meaning either he is picking up the snake or he is picking up the hose; the other four sentences were syntactically ambiguous, e.g., zijsluat de man met de stok, meaning either she is hitting the man who has the stick or she is using the stick 10 hit the man (see Fig. 2 for an example picture). The procedure was the same as for the

RECOVERY

FROM APHASIA

197

TABLE 2 TWENTY-EIGHT VARIABLES USED IN THE SPONTANEOUS SPEECH ANALYSIS Variable

Method of calculation

Speech tempo Communicative capacity Melody Articulation Utterance production Utterances shorter than six words

Number of words produced in 6 min Average of the evaluations of each 2-min sample Average of the evaluations of each 2-min sample Average of the evaluations of each 2-min sample Number of utterances produced in 6 min Number of utterances shorter than six words expressed as percentage of total number of utterances Number of words divided by number of utterances Number of complex utterances expressed as percentage of total number of utterances Number of seconds of speech which were incomprehensible in 6 min Number of self-corrections expressed as percentage of total number of utterances Number of automatisms expressed as percentage of total number of utterances Number of imitations of the test assistant expressed as percentage of total number of utterances Number of literal paraphasias expressed as percentage of number of content words Number of verbal paraphasias expressed as percentage of number of content words Number of neologisms expressed as percentage of number of content words Number of literal perseverations expressed as percentage of number of utterances Number of verbal perseverations expressed as percentage of number of utterances Number of substitutions of function words expressed as percentage of number of function words Number of deletions of function words expressed as percentage of number of utterances Number of deletions of content words expressed as percentage of number of utterances Number of syntactically confused structures expressed as percentage of number of utterances Ratio of number of content words to number of function words Number of nouns expressed as percentage of total number of words Ratio of personal pronouns to number of nouns Ratio of all pronouns to number of content words Number of word-order mistakes expressed as percentage of number of utterances Number of tense mistakes expressed as percentage of number of utterances Number of all other kinds of grammatical mistakes expressed as percentage of number of utterances

Mean length of utterance (MLU) Complex utterances Seconds incomprehensible Self-corrections Automatisms Imitations Literal paraphasias Verbal paraphasias Neologisms Literal perseverations Verbal perseverations Function-word

substitutions

Function-word

deletions

Content-word

deletions

Syntactic mixtures Content-word/function-word Nouns Personal pronouns Pronouns Word-order mistakes Tense mistakes Unclassified mistakes

ratio

198

PRINS, SNOW, AND WAGENAAR TABLE STRUCTURESTESTED

Structure

3 IN THE

Opposition tested

MCT Example sentence

(a) Subject pronouns

Male/female

He/she is walking street.

(b) Object pronouns

Male/female

The dog is biting him/her.

@I Possessive pronouns

Male/female

This is his/her hat.

(4 Possessive pronouns W Subject + object pronouns

Singular/plural

This is his/their dog.

Male/female

He hits him/her.

(0 Verb tense

Present/past

The girl swam/is swimming.

(l3) Verb tense W Prepositions of place

Present/future

The boy is going to saw/is sawing.

On/under

The ball is on/under the table.

(9 Prepositions of place

Next to/between

The girl is next to/between her parents.

(j)

Into/out of

The dog is jumping into/out of the basket.

(k) Prepositions of directions, double

From/onto, Onto/from

The cat jumps from the chair onto the table/from the table onto the chair.

(1) Word order of prepositions”

Place/direction

The man walks in/into the park.

(m) Comparative

Subject/object

The boy is bigger than the girl/ the girl is bigger than the boy.

(n) Word order

Subject/object

The girl is teased by the boy/ the boy is teased by the girl.

(0) Negationb

Indefinite affirmative/ negative

The boy is/is not wearing shirt.

Prepositions of direction

down

the

a

(1This opposition is expressed in Dutch by the placement of the preposition. The man walks in the park = De man loopt in het park. The man walks into the park = De mnn loopt

het park

in.

b This opposition is expressed in Dutch with the use of an indefinite negative article. The boy is wearing a shirt = De jongen draagt een overhemd. The boy is not wearing a shirt = De jongen draagt geen overhemd. MCT: Each sentence was read aloud to the patient, who was asked to point to the two pictures that went with it. [For a similar test, see Marcie, Jeanroy-Hecaen, & Htcaen (1972).] In addition to the MCT and the ACT, all of the aphasic patients were also given the Token Test (De Renzi & Vignolo, 1962), in its standardized Dutch version (Van Dongen et al., 1974). Since we were interested in linguistically more specific information than is given by this test, we will not report its results except to note that the correlation between the MCT and the Token Test was .81 and that the ACT correlated .75 with both the MCT and the Token Test (Pearson product-moment correlations, based on 74 patients). These high correlations confirm that the MCT and the ACT are valid and sensitive tests of comprehension disability.

RECOVERY

FROM APHASIA

199

FIG. 1. Example of pictures used for two items on the MCT. The patient was shown the top two pictures and asked which was correctly described by the sentence, “The girl is bigger than the boy.” For the bottom two pictures, the sentence was, “This is their mother.”

RESULTS Spontaneous Speech

A two-way analysis of variance was performed on each of the 28 variables, with Time (sessions I, II, and III) and Groups (NF, M, and F)2 as factors. The group differences at Time I have been the subject of an earlier paper (Wagenaar et al., 1975) and will not be discussed in any detail here. The means of the three groups on the 28 variables are given in Table 4, which also contains the means and standard deviations of the control group. Significant group differences were found for 15 of the 28 variables at Time I. These include all of the variables that are traditionally used to * The SNFgroup could not be included in the computer analysis, since they did not produce (enough) storable spontaneous speech (cf. Subjects section). Possible changes in the spontaneous speech of this group have therefore been assessed clinically.

200

PRINS, SNOW, AND WAGENAAR

FIG. 2. Example of pictures used for one item on the ACT. The patient was asked to point to the two pictures which were correctly described by the sentence, “She hits the man with the stick.”

distinguish fluent from nonfluent aphasics, e.g., Speech Tempo, MLU, Complex Utterances, Melody, Articulation, etc., while there were also significant differences in Communicative Capacity and in several variables reflecting various mistakes, like Literal Paraphasias, Word-Order Mistakes, etc. These results confirm that the groups differ greatly in most aspects of the spontaneous speech. The differences in Communicative Capacity, which can be seen as a measure of the severity of the aphasic deficit, suggest that in our patient group the NF patients were more severely affected than the F patients, with the M group in between. A comparison with the control group shows the same: In all cases the scores of the F group were closest to those of the control group, and on several variables there were no differences between these two groups (see Table 4). Of the 28 variables, 12 showed significant Time effects and 5 showed significant Time x Group interactions (see Tables 5 and 6). Of the Time effects, five can be seen as reflecting deterioration and five as reflecting improvement, while two are difficult to interpret as either improvement or deterioration. The five variables showing improvement were: Speech Tempo, Utterances s Five Words, MLU, Function-Word Substitutions, and Unclassified Mistakes. All of these variables showed changes in the

RECOVERY

FROM APHASIA

TABLE MEANS

OF THE

NF, M, 28

ON THE

AND

F

GROW-~

SWNTANEOUS

201

4 AND

CONTROL GROUP

OF THE

SPEECH

VARIABLES

Aphasic groups

Control (n = 18)

Variables

NF (a = 22)

M (n = 17)

F (a = 15)

Mean

Speech tempo** Communicative capacity** Melody** Articulation** Utterance production** Utterances c 5 words** Mean length of utterance** Complex utterances** Seconds incomprehensible Self-corrections* Automatisms Imitations Literal paraphasias* Verbal paraphasias Neologisms Literal perseverations Verbal perseverations Function-word substitutions Function-word deletions* Content-word deletions Syntactic mixtures** Content-wordlfunctionword ratio Nouns Personal pronouns* Pronouns** Word-order mistakes* Tense mistakes Unclassified mistakes

172.88 2.29 2.45 2.79 48.53 80.92 3.51 1.34 25.74 5.61 6.23 1.42 10.21 1.89 1.51 5.74 8.50 0.64 33.07 5.97 1.07

502.50 4.46 5.25 5.10 69.52 39.67 7.42 8.18 17.88 9.49 3.12 2.30 1.83 1.62 0.17 9.43 10.76 1.01 17.30 4.05 4.80

792.29 5.33 6.04 6.13 79.40 20.36 10.26 18.53 5.00 12.60 1.94 0.50 1.10 1.78 0.13 5.46 10.81 1.00 12.90 4.10 12.53

958.06 6.67 6.72 6.33 102.06 22.80 9.88 25.80 2.94 11.47 2.19 0.94 0.17 0.28 0.10 1.32 10.25 0.80 11.83 1.41 9.45

177.76 0.48 0.46 0.59 23.53 10.87 1.25 15.39 3.18 5.92 2.72 1.44 0.30 0.44 0.22 2.85 9.06 0.72 7.56 1.57 6.83

1.05 14.95 0.38 0.20 0.66 0.45 6.32

0.72 12.32 0.95 0.47 1.42 2.48 8.20

0.66 10.63 1.09 0.56 1.99 0.57 6.02

0.62 11.17 0.97 0.64 2.04 0.33 5.43

0.12 1.94 0.27 0.15 1.83 0.56 4.58

SD

* Difference among the aphasic groups significant, p < .Ol . ** Difference among the aphasic groups significant, p < .oOl.

direction of the control scores, but the aphasics’ scores at Time III remained considerably worse than those of the nonaphasics in all five cases. The three fluency indicators, Speech Tempo, Utterances s Five Words, and MLU, all showed the greatest improvement between Times I and II, with a slight deterioration between Times II and III. Speech Tempo showed a significant Time x Group interaction, because only the NF and the M patients showed improvement. Unclassified Mistakes also showed an interaction, with only the F group showing consistent improvement. Deterioration was seen in scores on Complex Utterances, Pronouns,

PRINS, SNOW, AND WAGENAAR

202

Literal and Verbal Perseverations, and Function-Word Deletion. Only on Literal Perseverations did all three patient groups show equal amounts of deterioration, from a level comparable to that of the control group at Time I to one considerably higher at Time III. Only the F group deteriorated on Complex Utterances, and only the F and M groups on Verbal Perseverations and Pronouns. Function-Word Deletion showed a marginally significant interaction (p < . lo), with only the NF group showing marked worsening. Self-Corrections and Syntactic Mixtures showed significant but difficult to interpret Time effects: The number of Self-Corrections decreased, which could be seen as improvement, except that by doing so it represents a TABLE MEANS

OF THE ON THE

APHASICS

28

(n

SPONTANEOUS

=

5 54)

FOR TIMES

SPEECH

I, II,

AND

III

VARIABLES

Variables

Time I

Time II

Time III

Speech tempo** Communicative capacity Melody Articulation Utterance production Utterances G 5 words** Mean length of utterance** Complex utterances** Seconds incomprehensible Self-corrections** Automatisms Imitations Literal paraphasias Verbal paraphasias Neologisms Literal perseverations** Verbal perseverations** Function-word substitutions* Function-word deletions* Content-word deletions Syntactic mixtures** Content-word/function-word ratio Nouns Personal pronouns Pronouns** Word-order mistakes Tense mistakes Unclassified mistakes**

424.1 3.8 4.2 4.3 64. I 55.9 5.91 10.3 17.7 11.5 5.3 2.2 3.1 2.1 0.7 3.2 5.7 1.3 20.7 4.7 3.8 1.1 13.0 0.71 0.46 1.70 1.07 7.10

466.8 3.7 4.3 4.4 63.9 47.6 7.01 6.9 18.4 8.6 3.8 1.1 4.6 1.7 1.3 9.3 12.7 0.6 18.4 4.8 6.9 0.7 13.6 0.75 0.36 1.27 1.81 9.26

452.2 3.9 4.4 4.5 62.8 50.5 6.89 7.6 16.4 6.2 3.2 0.9 7.5 1.5 0.1 7.8 11.1 0.6 28.6 5.0 5.6 0.7 12.2 0.80 0.33 0.82 0.42 4.05

* Difference among the three sessions significant, p < .05. ** Difference among the three sessions significant, p < .Ol.

RECOVERY

TABLE MEANS

203

FROM APHASIA 6

FOR THE NF, M, AND F GROIJ~~ FOR THE THREE TIMES ON THE SPONTANEOUS SPEECH VARIABLES WITH SIGNIFICANT GROUP x TIME INTERACTIONS

Time Variables

Group

Speech tempo**

NF M F

Unclassified mistakes**

NF

I

II

III

150.4 461.2 786.0

183.6 497.8 849.0

184.7 548.4 741.9

M F

4.25 8.06 10.26

12.36 9.08 4.92

2.34 7.34 2.80

Complex utterances**

NF M F

1.02 7.68 26.64

1.33 7.35 14.76

1.68 9.51 14.19

Verbal perseverations*

NF F

9.00 3.45 3.21

9.69 14.85 14.95

6.81 13.96 14.25

NF M F

.19 .61 .70

.22 .39 .52

.20 .40 .46

M Pronouns**

* Interaction significant, p < .05. ** Interaction significant, p < .001.

deviation from the mean of the control group; the number of Syntactic Mixtures, however, increased, changing in the direction that would seem less correct, but in the process approaching the mean score of the control group. These findings show the importance of a nonaphasic control group in interpreting results concerning spontaneous speech. Of the 12 significant Time effects, none except Literal Perseverations involved very large changes, especially when considered with regard to the rather large variances found for the control group. The amount of shift was, in all cases except Literal Perseverations, smaller than one standard deviation around the mean of the control scores. It is also important to note that Communicative Capacity, which reflects a clinical judgement of the severity of the aphasia, was one of the 16 variables that showed no time effect. Thus, the changes in spontaneous speech showed neither a clear pattern of improvement or deterioration nor any changes of great magnitude. In the spontaneous speech of the SNF group, there were also no clear changes in the course of 1 year. Most patients in this group still produced very few understandable words or only verbal stereotypies. Four patients,

204

PRINS, SNOW, AND WAGENAAR

0

I

II TIME

III

FIG. 3. Mean scores for the SNF, NF, M, and F groups at the three sessions on the MCT (maximum score = 60).

however, showed sufficient increase in speech production to become NF instead of SNF, but the quality of their speech in the last test session was still very poor. In other words, the increase in the amount of speech (Speech Tempo) did not correlate with an increase in Communicative Capacity. Sentence Comprehension The group differences on both the MCT and the ACT were tested with The Mann-Whitney U, and the change over time with the Wilcoxon signed-ranks test, since the skewed distribution of the scores made parametric tests inappropriate. The group differences on the MCT (see Fig. 3) suggest that the fluency classification correlated to a considerable extent with the severity of the receptive deficit, since the F group was best, followed by the M, NF, and SNF groups, in that order, at all three test sessions. The NF and M groups were significantly different from one another at all sessions. The M group was also significantly different from e:

o---of . . . . ..m o----Q “f )---t .rIf

E o------

0”

4’

iii

3..

i

e..

. . . ...***

o

__----

. . . . . . . ...*

_____

------

-0

. . . . . . . . * . . . . . . . . . .m .lo _______..__.___._...--.. --D

___._.--l

I .’

OL

I

II TIME

Ill

FIG. 4. Mean scores for the SNF, NF, M, and F groups at the three sessions on the ACT (maximum score = 8).

RECOVERY

FROM

205

APHASIA

the F group at Time II. All differences greater than these (e.g., between SNF and M or NF and F) were, of course, also significant. All of the groups showed significant improvement from Time I to Time III and from Time II to Time III. The SNF, NF, and F groups also improved significantly between Time I and Time II (see Fig. 3). On the ACT (as on the MCT) the F group received the highest scores, followed by the M, NF, and SNF groups, at all three sessions (see Fig. 4). Significant differences were found between the NF and M and between the M and F groups at all three test sessions; the differences between the SNF and the NF groups were significant only at Time II. Significant improvement was found for the NF and M groups from Time I to Time II, and for the F group from Time II to III. There were no qualitative differences among the groups in their performance on either comprehension test (Wagenaar & Prins, 1978). Individual

Cases

The fact that the patient group studied did not as a whole show any clear and consistent improvement in spontaneous speech does not imply that no such improvement occurred for individual patients (see Table 7). Of the total group of 74 patients, 11 showed sufficient increase in MLU and Speech Tempo to be reclassified on the fluency dimension (4 from SNF to NF, 2 from NF to M, 1 from NF to F, and 4 from M to F). Of these 11 patients, however, there was only 1 who showed a corresponding clear increase of two or more points on the rating scale for Communicative Capacity. Four other patients did show such a clear increase in Communicative Capacity, but they did not reclassify on the fluency dimension, as might be expected. The fact that in most cases a clear TABLE FREQUENCIES

7

OF PATIENTS SHOWING IMPROVEMENT, DETERIORATION, OR No CHANGE FLUENCY, COMMUNICATIVE CAPACITY, AND/OR THE MCT Morphosyntactic

Fk”CY

Improvement’ No change Deterioration

ON

Comprehension Test

Improvement”

No change

Deterioration

Communicative Capacity

Communicative Capacity

Communicative Capacity

Improvemen@

No change

Deterioration

Improvement

NO change

Deterioration

Improvemerit

No change

Deterioration

0 0 0

3 8 0

0 2 0

1 4 0

5 47 0

1 0 I

0 0 0

I 1 0

0 0 0

U Improvement or deterioration was defined as a change of one standard deviation or more. L Improvement or deterioration was defined ns a change of two or more points on the seven-point scale. ‘Improvement was defined as changing group classification in the direction of greater fluency; deterioration as changing group classification in the direction of less fluency.

206

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increase in fluency (and thus improvement on many of the 28 spontaneous speech measures) does not correspond to a clear increase in Communicative Capacity, and vice versa, may be explained by large individual differences in the specific communicative strategies adopted by the patients during the period of recovery. Such communicative strategies are apparently not easily captured by quantitative measures such as those employed in our study, although they are, of course, reflected in the Communicative Capacity measure. It can also be seen from Table 7 that improvement in either fluency or Communicative Capacity corresponds in only 3 out of 15 cases to a clear improvement (more than one SD) in sentence comprehension. Besides these cases in which there was clear partial improvement, there were also several cases in which there was clear deterioration in some aspects of language ability. From Table 7 it can be seen that one patient who changed from M to NF also showed a clear deterioration in Communicative Capacity, but without changing his level of sentence comprehension. There were three other patients whose aphasia became more severe (two points’ deterioration on Communicative Capacity): One of these reclassified from M to F, but stayed about the same in sentence comprehension, while the other two did not change their fluency classification, but did show some clear improvement in sentence comprehension (Table 7). DISCUSSION

The relatively old group of CVA patients studied showed no clear improvement as a group in spontaneous speech over the course of 1 year, but did show considerable improvement in comprehension ability during the same period. This finding seems to be in agreement with the results of Vignolo (1964), although a direct comparison cannot be made, since Vignolo has not examined spontaneous speech and did not specify whether the improvement in the comprehension of his patient group is the same for different types of aphasia. Our findings suggest that aphasic deficits in spontaneous speech production and in sentence comprehension are to some extent distinct, with their own recovery histories. The pattern of change over the course of 1 year was essentially the same for all four patient groups studied. This lack of differentiation is the more striking since the classification along the fluency dimension seems in this sample to correlate highly with the degree of severity of the aphasic disorder. Both for the expressive and for the receptive functions, the F group showed the smallest deficit, with the M, NF, and SNF groups showing progressively greater deficits. It has been suggested that the more severe aphasias have a poorer prognosis (Butfield & Zangwill, 1946; Sands et al., 1969; Sarno et al., 1970), but this position does not receive support from our findings; however, a comparison with

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APHASIA

207

other studies is again difficult to make since it is not always specified which types of patients do or do not show improvements on which tasks. For instance, Butfield and Zangwill (1946), in stating that the most favorable outcome is obtained in relatively mild and predominantly expressive aphasia, do not discriminate between expressive and receptive oral skills and do not define their language tasks adequately. The lack of differentiation among the SNF, NF, M, and F patients in degree of recovery does not exclude the possibility that some of the classical diagnostic types of aphasia recover better than others. The patient population available to us consisted for about 80% of mixed aphasias as far as the traditional classification system is concerned (as undoubtedly is the case for any unselected patient group). Since in our sample the relatively few “pure types” are mainly Broca’s aphasics (12 of the 19 classifiable pure types; Van der Sandt-Koenderman, 1976), no conclusion is possible from our data concerning the differential prognosis for the different classical aphasic subtypes. It is worth noting that many of the spontaneous speech characteristics traditionally considered indicative of aphasia occurred with comparable frequency in the spontaneous speech of the nonaphasic control subjects. Literal and Verbal Perseverations, Word Deletion, Word Order and Unclassified Mistakes, and even Verbal Paraphasias occurred surprisingly often in the normals’ speech. Presumably they are only so frequent in fast, informal, and “sloppy” speech such as that analyzed here, and would not occur in more careful speech (Labov, 1970). It seems likely that the aphasics, on the other hand, cannot avoid these mistakes even in careful and simple speech, because of a breakdown in the accessibility and retrieval of different linguistic structures. A comparison of the aphasics with the control group also reveals that the F patients’ speech is very similar to that of normals, but on all indexes of fluency is less fluent than normals’ speech. It should again be noted, however, that our F group contained relatively many (60%) patients with a mild, mixed aphasia and no real Wernicke patients. Wernicke aphasics, who are so often described in the literature, may be absent from our sample because archetypical instances of Wernicke’s aphasia are relatively rare and because they tend to occur mainly in the first stages of the aphasia (Lecours & Vanier-Clement, 1976). The fact that, in general, greater improvement occurred for sentence comprehension than for spontaneous speech may be explained in several ways: (1) Speech production is inherently more difficult than comprehension. A speaker must himself plan what he is going to say (semantic intent) and how to say it (selection of lexical items and application of syntactic rules), whereas a hearer has the much more restricted task of interpreting ready-made linguistic structures. Comprehension of much speech can

208

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occur with minimal syntactic analysis, by relying on lexical analysis, heuristic strategies, and knowledge of the world (Fodor, Bever, & Garrett, 1974). Comprehension normally precedes production in both first and second language acquisition. It is, thus, not surprising that aphasic patients’ receptive abilities recover better than their production. (2) Although much is still unknown about the way language is represented in the brain, it has often been suggested that the minor hemisphere may play a role in recovery from aphasia, not only in left-handed or ambidextrous patients (Luria, 1970), but also in some right-handed patients (Kinsbourne, 1971; Czopf, 1972). One might also conjecture that the role of the right (minor) hemisphere in recovery from aphasia may be different for different functions, i.e., that its role may be more apparent for receptive than for expressive functions. This hypothesis is corroborated by the fact that children who become aphasic during or shortly after the period of language acquisition have mainly expressive symptoms (Alajouanine & Lhermitte, 1965), which may be explained by the minor hemisphere’s taking over (Lenneberg, 1967). Even in adults, where the plasticity of the nervous system is said to be far less extensive, there is some evidence that the minor hemisphere is capable of considerable language comprehension. Verbal comprehension is still possible in some patients whose left hemisphere is anesthetized by sodium amytal (Milner, 1967) or removed altogether by hemispherectomy (Burklund, 1972). Furthermore, experiments with split-brain patients (Sperry & Gazzaniga, 1967) have shown that the right hemisphere, although practically “mute,” is able to “understand” fairly complex syntactic and semantic structures (Zaidel, 1973). It cannot be assumed that the same applies to normal people or aphasic patients without commissurotomy, since there are many aphasic patients who do very poorly on both expressive and receptive linguistic tasks and who do not show any significant recovery, in spite of possessing a normal, intact right hemisphere. In view of the complexity of the brain and possible individual differences in its structure and function, this sort of conflicting evidence is not surprising. [For a theory that tries to reconcile the conflicting results, see Moscovitch (1976a, b).] The possibility that the right (minor) hemisphere plays some role in the recovery of verbal comprehension in at least some aphasic patients can certainly not be disregarded. (3) The fact that, in general, greater improvement occurred for receptive than for expressive abilities might also be related to the nature of the therapy given to the patients. The exact content of the therapy sessions was highly variable, dependent on the patient, the treatment center, and the speech therapist involved. However, it seems very likely that the skills needed for the comprehension tests were more similar to those practiced in the therapy sessions than the much more complex spontaneous speech skills. Since almost all of the utterances a speaker produces or a hearer

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209

understands are novel (Chomsky, 1963, it is easy to see that the linguistic structures possible in spontaneous speech can hardly be practiced by specific training methods. This interpretation is supported by the fact that our patients’ expressive skills in the more restrictive language tasks (e.g., confrontation naming, phrase repetition, sentence production) did improve over the course of 1 year, whereas their performance in word fluency, which tests spontaneous production, did not improve. Of all the tests mentioned above, the two comprehension tests described in this study showed the greatest amount of change (20% for the MCT and 48% for the ACT, the mean gain for all tests together being 15%; seeHet herstelverioop van afasie, 1976).

Without a controlled comparison of the effects of different types of therapy and without the use of a matched group of control patients receiving no therapy at all, it is impossible to decide which of the three possibilities mentioned above is correct or whether all three factors might not play a role. Whatever the explanation for the finding of greater improvement in comprehension than in spontaneous speech, it remains very encouraging that a patient group such as ours, characterized by none of the factors generally thought to promote improvement, did show considerable recovery in some important aspects of their linguistic abilities. REFERENCES Alajouanine, T., & Lhermitte, F. 1965. Acquired aphasia in children. Brain 88, 653-662. Benson, D. F. 1967. Fluency in aphasia: Correlation with radioactive scan localization. Cortex

3, 373-392.

Burklund, C. W. 1972. Cerebral hemisphere function in man. Fact versus tradition. In W. L. Smith (Ed.), Drugs, development, and cerebra/function. Springfield, II: Charles C Thomas. Pp. 8-36. Buttield, E., & Zangwill, 0. L. 1946. Re-education in aphasia: A review of 70 cases. Journal of Neurology,

Neurosurgery,

and Psychiatry

29, 467-471.

Chomsky, N. 1965. Aspects ofthe theory of syntax. Cambridge, MA: MIT Press. Culton, G. L. 1969. Spontaneous recovery from aphasia. Journal of Speech and Hearing Research

12, 825-832.

Czopf, J. 1972. Uber die Rolle der nich dominante Hemisphare in der Restitution der Sprache der Aphasischen. Archiv fiir Psychiatric und Nervenkrankheiten 216, 162- 171. Darley, F. L. 1972. The efficacy of language rehabilitation in aphasia. Journal of Speech and Hearing

Disorders

37, 3-21.

Darley, F. L. 197.5. Treatment of acquired aphasia. in W. J. Friedlander (Ed.), Advances in Neurology. New York: Raven Press. Vol. 7, pp. 111-145. De Renzi, E., & Vignolo, L. A. 1962. The Tokentest: A sensitive test to detect receptive disturbances in aphasics. Brain 85, 665-678. Fodor, J. A., Bever, T. G., & Garrett, M. F. 1974. The psychology of language. An introduction topsycholinguistics andgenerativegrammar. New York: McGraw-Hill. Gloning, K., Trappl, R., Heiss, W.-D., & Quatember, R. 1976. Prognosis and speech therapy in aphasia. In Y. Lebrun & R. Hoops (Eds.), Recovery in aphasics. Amsterdam: Swets & Zeitlinger. Pp. 57-62.

PRINS, SNOW, AND WAGENAAR

210

Godfrey, C. M., & Douglass, E. 1959. The recovery process in aphasia. Canadian Medical Association Journal 80, 618-624. Goodglass, H. 1968. Studies on the grammar of aphasics. In S. Rosenberg & J. H. Koplin (Eds.), Developments in applied psycholinguistics research. New York: Macmillan. Pp. 177-208. Goodglass, H., & Kaplan, E. 1972. The assessment of aphasia and related disorders. Philadelphia: Lea & Febiger. Het herstelverloop de Stichting

van afasie. Een psycholinguistisch Afasie Nederland, 1971-1975.

onderzoek

uitgevoerd

in opdracht

van

1976. door H. Richters, E. Wagenaar e.a. onder wetenschappelijke begeleiding van B. Deelman e.a. Amsterdam. Kerschensteiner, M., Poeck, K., & Brunner, E. 1972. The fluency-nonfluency hypothesis in the classification of aphasic speech. Cortex 8, 233-247. Kinsbourne, M. 1971. The minor cerebral hemisphere as a source of aphasic speech. Archives of Neurology

25, 302-306.

Labov, W. 1970. The study of language in its social context. Studium Generale 23, 30-87. Lebrun, Y. 1976. Comments after paper by Samo. In Y. Lebrun & R. Hoops (Eds.), Recovery in aphasics. Amsterdam: Swets & Zeitlinger. Pp. 28-30. Lecours, A. R., & Vanier-Clement, M. 1976. Schizophasia and jargonaphasia. A comparative description with comments on Chaika’s and Fromkin’s respective looks at “schizophrenic” language. Brain and Language 3, 516-565. Leischner, A. 1972. Uber den Verlauf und die Einteilung der aphasischen Syndrome. Archiv fiir Psychiatric und Nervenkrankheit 216, 219-231. Leischner, A. 1976. Aptitude of aphasics for language treatment. In Y. Lebrun & R. Hoops (Eds.), Recovery in aphasics. Amsterdam: Swets & Zeithnger. Pp. 112- 120. Lenneberg, E. 1967. Biological foundations of language. New York: Wiley. Luria, A. R. 1970. Traumatic aphasia: Its syndromes, psychology and treatment. The Hague: Mouton. Milner, B. 1967. Discussion on cerebral dominance in man. In C. H. Millikan & F. L. Darley (Eds.), Brain mechanisms underlying speech and language. New York: Grune and Stratton. Pp. 177- 184. Moscovitch, M. 1976a. On the representation of language in the right hemisphere of right-handed people. Brain and Language 3, 47-71. Moscovitch, M. 1976b. On interpreting data regarding the linguistic competence and performance of the right hemisphere: A reply to Seines. Brain and Language 3, 590-m.

Orgass, B., & Poeck, K. 1966. Clinical validation of a new test for aphasia: An experimental study on the Token Test. Cortex 2, 222-243. Parisi, D., & Pizzamiglio, L. 1970. Syntactic comprehension in aphasia. Cortex 6, 204-215. Poeck, K., Kerschensteiner, M., & Hartje, W. 1972. A quantitative study on language understanding in fluent and nonfluent aphasia. Cortex 8, 299-304. Sands, E. S., Samo, M. T., & Shankweiler, D. P. 1969. Long-term assessment of language function in aphasiadue to stroke. Archives ofPhysical Medicine and Rehabilitation 50, 202-207.

Samo, M. T. 1976. The status of research in recovery from aphasia. In Y. Lebrun & R. Hoops (Eds.), Recovery in aphasics. Amsterdam: Swets & Zeitlinger. Pp. 13-28. Samo, M. T., & Levita, E. 1971. Natural course of recovery in severe aphasia. Archives of Physical Medicine and Rehabilitation 52, 175- 179. Samo, M. T., Silverman, M. G., & Sands, E. S. 1970. Speech therapy and language recovery in severe aphasia. Journal of Speech and Hearing Research 13,607-623. Schreuder, J. Th. R. 1973.20 jaar geriafrie, een keuze uit her M,erk van -, samengesteld onder redaktie van L. A. Cahn, J. M. A. Munnicks, &J. Schouten. Deventer: Van Loghum Slaterus.

RECOVERY

FROM APHASIA

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Shewan, C. M., & Canter, G. J. 1971. Effects of vocabulary, syntax and sentence length on auditory comprehension in aphasic patients. Cortex 7, 209-226. Sperry, R. W., & Gazzaniga, M. S. 1967. Language following surgical disconnection of the hemispheres. In C. H. Millikan & F. L. Darley (Eds.), Brain mechanisms underlying speech and language. New York: Grune and Stratton. Pp. 108- 121. Van de Sandt-Koenderman, M. 1976. Klassifkatie van afasiepatiinten. Unpublished M. A. thesis. Amsterdam: Institute for General Linguistics, University of Amsterdam. Van Dongen, H. R., Van Harskamp, F., Verhey-Stall, F. W., & Luteijn, F. 1974. Afasie-onderzoek met de Token-test. Enige psychometrische kenmerken en evaluatie van een verkorte vom~. Nederlands Tijdschrift voor de Psychologie 28, 633-647. Verhage, F. 1964. Infelligentie en leeftijd bij volwassenen en bejaarden. Assen: Van Gorcum. Vignolo, L. A. 1964. Evolution of aphasia and language rehabilitation: A retrospective exploratory study. Cortex 1, 344-367. Wagenaar, E., & Prins, R. S. 1979. Comprehension abilities of aphasic patients (in preparation). Wagenaar, E., Snow, C., & Prins, R. 1975. Spontaneous speech of aphasia patients: A psycholinguistic analysis. Brain and Language 2, 281-303. Zaidel, E. 1973. Linguistic competence andrelatedfunctions in the right cerebral hemisphere of man following commissurotomy and hemispherectomy. Unpublished doctoral thesis. Pasadena: California Institute of Technology.