Chapter 2
Aphasia types and the struggle to classify
In this chapter, the classical aphasia types will be presented: Broca’s
aphasia, Wernicke’s aphasia, anomic aphasia, conduction aphasia,
transcortical sensory and motor aphasia, global aphasia. The impairments
to production and comprehension will be discussed, with the focus on
spoken language, although the impairments to written language are given
as well. Considering that aphasia is a central language disorder, the
impairments to written language are usually similar or worse than in
spoken language. Where possible, the connections between aphasia
syndrome and lesion site will be mentioned. This will result in a
schematic overview. The fact that the classic aphasia types are not as
common as sometimes suggested will be discussed after the presentation
of the syndromes. We will demonstrate, however, the importance of
classification and why some researchers continue to classify their
subjects notwithstanding the inherent problems.
Introduction
Aphasia can manifest itself in different signs and symptoms, depending on the size and
location of the lesion. Usually, lesions in the left frontal lobe result in mainly grammatical
problems and more posterior lesions, in the temporal and/or parietal lobe, in lexical-semantic
1
problems. Several clusters of symptoms appear more often than others. These are classified in
a number of aphasia syndromes. These are the so-called classical aphasia types. Most of these
syndromes are associated with a specific lesions site. These links between syndromes and
lesion sites were, until around 1970, establish by post-mortem studies. Even then it was clear
that there is no simple one-to-one relationship between symptoms and lesion site. This
became even clearer with the advent of neuro-imaging techniques. First, CT-scanning
(Computer Tomography) enabled the neuroscientists to see the brain lesions in vivo, and since
1980 other techniques, such as PET (Positron Emission Tomography) and fMRI (functional
Magnetic Resonance Imaging) have made it possible to view brain activity during, for
example, language tasks. The findings suggest that there is no one-to-one relationship
between aphasia symptoms and lesion site. However, in our view, the use of clinical
syndromes remains useful for both research and clinical purposes.
Here we use the classification that is common in the Western world. We also introduce terms
used by Luria, a very influential Russian neuropsychologist, but these need to be read with
caution as sometimes the match across syndromes is not exact. Thus one needs to be aware
that they are not just different labels of the same syndrome. Luria’s approach was different
from the Western one, so his descriptions are different in nature. Therefore, there is no clear
one-to-one relation between the syndromes in the Western world and Russian tradition.
Broca’s aphasia
Broca’s aphasia is called after Paul Broca, although his description does not match with the
symptoms we now assume under the term. His description and supposition about location in
the brain concerns articulation. This he located in the foot of the third frontal gyrus and called
‘le siège de la faculté du langage articulé’, the seat of the faculty of articulated language. This
suggests that the disorder he referred to was probably more likely to be what we now call
2
apraxia of speech. Nowadays, the term ‘Broca’s aphasia’ is used to capture the cluster of
symptoms that is most often the result of a lesion in or around Broca’s area. Broca’s aphasia
may also be referred to as ‘agrammatism’ (although these terms are not synonymous),
suggesting that grammar is impaired. In the Russian tradition, Broca’s aphasia is labeled
‘efferent motor aphasia’.
Speech production is nonfluent, meaning that the number of words per minute is low. It is
characterized by what has been called telegraphic speech (mainly content words) and
relatively good comprehension. Understanding of spoken language in daily live is reasonable
good, but when the patient is tested, comprehension problems are revealed.
Reading and writing are often impaired, parallel to or worse than comprehension and
production of spoken language. Repetition of single words is usually good, although
repetition of function words may be worse than repetition of content words. Repetition of
sentences results in telegraphic speech.
Individuals with Broca’s aphasia may have problems with articulation. Some researchers
include poor articulation in their definition of Broca’s aphasia, but there are certainly patients
who speak telegraphically, but whose articulation is normal. Co-occurrence of telegraphic
speech and articulation problems is due the fact that lesions that cause Broca’s aphasia often
include (parts of) the motor strip, resulting in articulation problems and/or hemiplegia (most
patients with Broca’s aphasia are paralyzed at the right-side). So the relationship between
telegraphic speech and articulatory deficits is anatomically-based rather than based on a
natural co-occurrence of motor speech problems and agrammatism. Articulation organs are
represented bilaterally, however, and these motor speech problems often resolve, because the
right hemisphere compensates. However, Broca’s aphasia is often accompanied by apraxia of
speech, also for anatomical reasons, but not necessarily so. Below is an example of the
telegraphic speech in an individual with Broca’s aphasia who answers the question do you
3
have any plans for Sinterklaas, a Dutch family day. The questions of the interviewer are in
italics.
Example of spontaneous speech of a patient with Broca’s aphasia
no plans no no Sinterklaas shop business .. my purse always empty … future
… no past are you going to give presents no absolutely not! in the pot tasty
things … snacks, tasty so no presents no no and what are you going to do
for Christmas? eat tasty things presents Christmas draw numbers all get
presents ten guilders … ten guilders each you are not going away? no we
sold house .. our house … new around March we saving pennies
As this sample illustrates, many, but not all, function words are left out, many verbs are nonfinite (but notice the low number of verbs). Still, the produced speech is can be understood
and this patient has no articulatory disorder. Also, the speech is not completely agrammatic:
the adjectives and determiner precede the nouns. A more accurate description is that the
fragments produced comply with some grammatical rules. These utterances have been likened
to grammatical ellipses. The term ‘agrammatism’, literally meaning ‘no grammar’ is, hence,
not complete correct. One of the defining terms of Broca’s aphasia is ‘telegraphic speech’.
Nevertheless, some researchers include aphasic patients who do not speak at all or only
produce ‘yes’ and ‘no’, but who do have relatively good comprehension in groups studies on
Broca’s aphasia, especially when these studies focus on language comprehension. This is not
a priori wrong: as said above, Broca’s aphasia is often accompanied by apraxia of speech,
which may hide the telegraphic output, although the underlyingly disorder is a Broca’s
aphasia. The term ‘agrammatism’ is very commonly used instead of ‘Broca’s aphasia’, which
indicates that the subjects have an output that is typical of Broca’s aphasia.
4
Wernicke’s aphasia
Wernicke’s aphasia is named after Carl Wernicke, who was the first to describe the symptoms
of this aphasia type. In the Russian literature, Luria refers to this aphasia as ‘sensory aphasia’
or ‘acoustic-gnostic aphasia’. The lesion associated with this type of aphasia is usually in the
posterior parts of the superior gyrus of left temporal lobe, nowadays known as ‘Wernicke’s
area’.
Speech production is fluent but has verbal and/or literal paraphasias and/or neologisms and in
some patients speech is incomprehensible, because the frequency of these errors. Then
speech production is called ‘jargon’ or ‘word salad’. Language comprehension is impaired,
because the patients have problems with understanding single words and, therefore, with
understanding sentences. This means that communication with these patients is usually very
difficult, because the conversational partners do not understand each other.
Repetition, reading aloud and silent reading of words and sentences is impaired, as is writing.
An example of spontaneous speech of a Wernicke’s patient is given below. This patient’s
communication level is very low, but the text is very well articulated and fluent. The question
of the interviewer is in italics. The utterance boundaries are indicated by / / to facilitate
reading, but the whole sample is without pauses. The intonation is normal.
Example of spontaneous speech of a patient with Wernicke’s aphasia
How are you these days? I’ve got the idea that I’ve been taken better / you
can hear that with the talking of course/ on one side but I think it’s nice, my
idea too / but if it does not work then it does not work / I think quite easy
about that / we never say it is not possible or it does not work / and that's
what I did / that’s the way I am, right?
5
This sample is barely comprehensible, as is the rest of this patient’s speech, although it is hard
to point to the errors. Very little specific information is given despite some well formed
sentences and a range of word types: many function words are used and the nouns and verbs
produced are highly frequent. Although the problems of patients with Wernicke’s aphasia are
mainly lexical, the sentences are often ungrammatical. This mixing up of sentence structures
(‘on one side but I think it’s nice, my idea too’) is called ‘paragrammatism’
Anomic aphasia
Anomic aphasia is associated with left posterior lesions (temporo and/or parietal lobe), but no
specific lesion site can be given. Anomic aphasia is also called ‘amnestic aphasia’; in the
Russian tradition it is called ‘acoustico-mnestic aphasia’.
Speech production of anomic patients is fluent, but characterized by word-finding problems.
The word-finding problems can show up in different ways, even within the same patient.
Sometimes there are long pauses, sometimes the patients indicate that they cannot find the
word (‘what is it called?’ ‘I know what it is, but I cannot find the name’ etc.), or they describe
what they mean. These descriptions are called ‘circumlocutions’. Another strategy,
consciously done or not, is that high-frequency, more general words are used, with which
little information is provided. This is called ‘empty speech’. Anomic patients may
occasionally use paraphasias, but this is not a main characteristic.
Comprehension of words and sentences in anomic aphasia is relatively good in a
conversation, but when comprehension of grammatically complex sentences is formally
tested, problems may appear. Repetition of words and sentences and reading aloud and
silently is reasonable good, but in writing the word-finding problems are similar to those in
spoken output.
6
Below an example of an anomic patient’s spontaneous speech is given. The patient has told
the interviewer that he played a game with two children and the interviewer then asks which
game that was. He cannot find the name and starts to describe the game (which is
Pelmanism). The question of the interviewer is in italics, pauses are indicated by …
Example of spontaneous speech of a patient with anomic aphasia
So you played a game. Which game was it? the name I don’t know the name
… err ... yes … a lot of people usually can do it ... this big ... and you have
to put it under .. upside down, do it right … you have to watch two on top of
each other … 40 or 50 things for sure and this and that on the side but this
one should be the same this ... if this one is not the same it will go oops-adaisy back … yes but the name .. I do not know the name but I’ve played it
six or seven times … something like that, no more, because more often... no
rather not … the children would love to but I said I won’t do it anymore.
Although the description of the game is fairly efficient (80% of the students guess the name of
the game correctly after watching the sample), the word-finding problems are evident. The
nouns that are produced are not very specific and there are many pauses. Nevertheless, the
patient is able to convey what he wants to say.
Conduction aphasia
Conduction aphasia was first described by Carl Wernicke. He used the German word
‘Leitungsaphasie’, from which the term ‘conduction aphasia’ is literally translated. According
to Carl Wernicke, conduction aphasia arises when the connection between Wernicke’s area
(where the word images are stored) and Broca’s area (where the sound images are stored) is
7
distorted. He, wrongly, assumed that the lesion was in the left arcuate fasciculus. Nowadays,
lesions to the left supramarginal gyrus are held responsible for conduction aphasia, but as said
before, there is no one-to-one relationship between lesion site and syndrome for any of the
aphasia types. The Lurian term for conduction aphasia is ‘afferent motor aphasia’.
Patients with conduction aphasia speak fluently, but their speech is characterized by
substitutions, transpositions, omissions and additions of phonemes, called ‘phonemic
paraphasias’. They can retrieve the correct item from the lexicon, but errors occur when
producing the correct phonemes for the target word or ordering the phonemes in the correct
order for the target word. These errors appear in all production tasks (also in reading aloud
and writing), but are most prominent in repetition. Comprehension of spoken and written
language is relatively intact, although long, grammatically complex sentences may be hard to
understand for patients with conduction aphasia. Since the patients’ comprehension is
relatively spared, they hear their phonemic errors and try to correct them, not always with a
positive result. This repetitive behavior is called ‘phonemic approximation’. When many
phonemic paraphasias are produced, the fluency of the speaker may decrease, but parts of
speech will still be fluent, especially those parts that contain mainly function words; the
phonemic paraphasias usually involve content words.
Below is a speech sample of a patient with conduction aphasia. He was asked what he prefers
to do in his spare time. He makes it clear that he likes reading, but there is something else that
he likes to do as well, which, as it turns out, is the game Scrabble. The questions of the
interviewer are in italics, the phonemic approximations are underlined.
Example of spontaneous speech of a patient with conduction aphasia
we I I we I like to do st ss stap strappen stap do you know that? Reading?
that is not reading of course stram stram stramplen cartoons? no no … also
8
yes … but this is called stram strample strapple
I don’t understand
strampen reading worte worte wor …such a card, don’t you know that? then
you must all those then you must those those wo wo wo works words …
you start with a word of six letters and then you have a thing in front of you
and then you select those letters and then you say that and that … scrabble?
yes!!
As is demonstrated with this sample, the phonemic approximations do not always come near
to the target phonemes.
Conduction aphasia is thought to be relatively rare. This might be because it usually improves
very rapidly (within the first few weeks), so in the subacute and chronic stages there are not
many patients with conduction aphasia.
Transcortical aphasia
‘Transcortical’ refers to the fact that the lesions in this type of aphasia are rather widespreaded over (‘trans’) the cortex. These lesions are supposed not to involve the classical
language areas, but typically affect the areas surrounding them, and thus, isolating the
language areas from the rest of the brain. Two types of transcortical aphasia are distinguished:
transcortical sensory and transcortical motor aphasia. Transcortical sensory aphasia has not
been described by Luria. The lesion in this aphasia type isolates Wernicke’s area from the rest
of the brain, the area of the brain where words are represented. This part of language is then
still intact. However, in order for a word to be understood or produced, the rest of the cortex is
needed, since the concepts (the abstract meanings) are probably widely represented over the
brain. The disconnection of the concepts and words implies that words are no longer
understood or correctly produced. The prominent characteristic of transcortical sensory
9
aphasia is that the patient is able to repeat words and sentences relatively well, since the
language areas needed for this are still intact. However, the patient will not understand what
he of she is repeating. Also, there will hardly be any spontaneous output, since ideas and
concepts, formed all over the brain, cannot reach Wernicke’s area where the words are stored.
So, basically, transcortical sensory aphasia resembles Wernicke’s aphasia in a great respect
(poor comprehension, fluent production larded with paraphasias and neologisms); contrary to
a patient with Wernicke’s aphasia, a patient with transcortical sensory aphasia is able to
repeat. It has been reported that these patients may change pronouns to their own orientation.
When the patient is asked to repeat the sentence ‘you have a smart dress on’, this may be
repeated as ‘I have a smart dress on’. In severe cases, no communication is possible at all: the
patient is only repeating what is heard and / or is reciting prayers or singing songs rather
flawlessly.
In patients with transcortical motor aphasia, the frontal language regions are isolated from the
rest of the brain. Since Wernicke’s area is intact, comprehension is relatively well-spared and
so is repetition. However, the patient will not produce language spontaneously, although
automatic answers may appear. When a patient sees a picture of a tree, he will not be able to
name the picture, but a semantic cue, such as ‘apples grow on a …..’ might help to elicit the
target word. The output of patients with transcortical motor aphasia may be as poor as in
severe Broca’s aphasia, but the distinctive characteristic of transcortical motor aphasia is the
ability to repeat sentences, something patients with Broca’s aphasia cannot do.
Because of the typicality of the lesions, pure transcortical aphasias are very rare.
Global aphasia
Global aphasia is usually associated with large lesions, which might include both Broca’s and
Wernicke’s area. In global aphasia all language modalities are severely affected and it may be
10
accompanied by apraxia of speech. Speech production is nonfluent and often restricted to one
and two word utterances that do not provide much information. Sometimes the output is
restricted to ‘yes’ and ‘no’, although these do not always convey the intended meaning.
Comprehension of both spoken and written words and sentences is poor. Repetition, reading
aloud and writing is also severely affected.
Considering the severity of this aphasia type, it is clear that communication with these
patients is very difficult indeed.
Summary
In the sketches of the classical aphasia types, the dimension of oral language processing along
which the syndromes have been described were ‘fluency’, ‘comprehension’ and ‘repetition’.
Apart from that, some characteristics have been provided. In Table 1, the classical aphasia
syndromes have been schematically summarized along these dimensions.
Table 1: An overview of the classical aphasia syndromes (- means impaired, + means
relatively intact; transc. sens. aphasia = transcortical sensory aphasia; transc. mot. aphasia =
transcortical motor aphasia).
fluency
comprehension
repetition
Broca’s aphasia
-
+
-
telegraphic speech
Wernicke’s aphasia
+
-
-
paraphasias
anomic aphasia
+
+
+
word-finding problems
conduction aphasia
+
+
-
phonemic paraphasias
transc. sens. aphasia
+
-
+
repetition relatively spared
transc. motor aphasia
-
+
+
repetition relatively spared
global aphasia
-
-
-
all modalities impaired
11
characteristics
The struggle to classify
As said in the introduction of this chapter, patients with a classical aphasia type are not
common, usually there is a so-called ‘mixed aphasia’. Nevertheless, pure aphasia syndromes
do occur and can reveal much about how language is represented in the brain. Much research
that has involved group studies, has focussed on the representation of language, aim to recruit
aphasic subjects with aphasia that is typical of one syndrome. The aim is to work with a more
or less homogeneous groups of typical patients.
A problem with the classical aphasia types is that they are not always as clear as one would
wish. Estimations of the frequency of pure aphasia types vary from 20-30 % (Prins et al.,
1978; Albert et al., 1981) to almost 100% (De Renzi et al., 1980). This is, of course,
dependent on the definitions of the syndromes and on the criteria used to draw boundaries
between the syndromes, but even Goodglass (1981) finds that “fewer than half of the patients
can be assigned with confidence to one of the standard syndromes” (Goodglass, 1981, p2).
For example, one of the characteristics of Broca’s aphasia is ‘telegraphic speech’: over-usage
of content words (such as nouns, verbs and adjectives) on the one hand and omissions and/or
substitutions of function words (such as determiners and prepositions) and grammatical
morphemes (such as verb inflection and plural affixes of nouns) on the other. Some
researchers include patients who do not talk at all in this syndrome, others do not. Another
example of a classification problem concerns Wernicke’s aphasia. This is characterized by
poor comprehension, but there are aphasiologists who include Wernicke patients with
‘relatively’ good comprehension.
Knowing that the group of patients belonging to a certain aphasia type may be rather
heterogeneous, one can wonder why researchers bother about aphasia types at all and, indeed,
several aphasiologists prefer to perform single-case studies or group studies with patients not
12
selected for aphasia types, to circumvent this classification problem. However, if one wants to
draw generalizations of symptoms and, even more interesting, establish the relationship
between them, studying the aphasic syndromes is the best way. This has been an important
point of debate at the end of last century. We will come back to this in the chapter on current
issues.
Suggested further reading
On the classical aphasia types:
Goodglass, H., Kaplan, E. Barresi (2000) The Assessment of Aphasia and Related Disorders.
Third Edition, Baltimore: Lippincott, Williams and Wilkins.
Luria, A.R. (1973) The Working Brain Baltimore: Penguin Books Ltd.
On Broca’s aphasia:
Kean, M.-L. (1985) Agrammatism. Orlando: Academic Press. An edited volume on Broca’s
aphasia.
H.A. Whitaker (1997) Agrammatism. San Diego: Singular Press. An edited volume on
experimental studies on Broca’s aphasia
Menn, L. & Obler, L.K. (1990): Agrammatic Aphasia: A cross-language narrative
sourcebook. Amsterdam: John Benjamins. A large collection with spontaneous
speech an experimental data of patients with Broca’s aphasia in many different
languages, including more exotic ones.
On the fluent aphasias:
Edwards, S.
(2005) Fluent Aphasia. Cambridge University Press. The difference from
nonfluent aphasia, focused on Wernicke’s aphasia.
13
Kohn, S.E. (1992) Conduction Aphasia. Hillsdale: Lawrence Erlbaum. An edited volume on
conduction aphasia,
References
Goodglass, H. (1981) The syndroms of aphasia: Similarities and differences in neurolinguistic
features. Topics in Language Disorders, 1, 1-14.
Albert, M.L., Goodglass, H., Helm, N.A., Ruberns, A. & Alexander, M.P. (1981) Clinical
Aspects of Dysphasia. New York: Springer Verlag.
Prins, R.S., Snow, C.E. & Wagenaar, E. (1978) Recovery of aphasia: Spontaneous speech
versus language comprehension. Brain and Language, 6, 192-211.
De Renzi, E., Faglioni, P. & Ferrari, P. (1980) The influence of sex and age on the incidence
and type of aphasia. Cortex, 16, 627-630.
14