Characterizing Subtle Deficits in Mild Aphasia: A Clinical Case Study


Aphasia is a communication disorder caused by neurological damage to the language centers of the brain; aphasia affects approximately one million Americans. In clinical practice, standardized tests are often found to be insensitive to the subtle communication deficits reported by individuals with mild aphasia. The current study examines an approach to assessing the communicative functionality of an individual with mild aphasia who reports residual communication deficits despite normal test scores. A personal story told by the client is analyzed on two dimensions of functional storytelling: the use of character (who) and the use of time (when), both of which are essential components of successful storytelling. Results suggest that the client’s ability to express character was relatively preserved, but his ability to express time was relatively disrupted. Findings hold implications for the design of aphasia assessment and treatment.

Table of Contents: 


    Aphasia is an acquired communication disorder resulting from a neurological injury, such as stroke, to the language centers of the brain. Approximately 1 in every 250 people in the United States has aphasia (National Aphasia Association, 2009). Aphasia affects the ability to process language, both expressive language and receptive language; it impacts speaking, writing, reading and listening. The impairments associated with aphasia often significantly affect every-day communicative functionality (Elman & Bernstein-Ellis, 1995).

    Speech-language therapy will often improve a patient’s day-to-day functionality for communication. However, a clinician must first be able to identify the deficits associated with a client’s aphasia. Standardized tests are beneficial tools for diagnosis, but the knowledge gained from these tests is not a comprehensive picture of a client’s ability to demonstrate communicative functionality. Often, individuals with mild forms of aphasia still complain of residual communicative deficits, yet standardized tests are not sensitive enough to capture subtle deficits. Although this special population is usually in need of services, the individuals do not always receive the therapy that is needed to achieve communicative functionality and higher quality of life (Elman & Bernstein-Ellis, 1995). The purpose of the current case study is to identify ways to analyze subtle communication deficits of individuals with mild forms of aphasia.  This study addresses how to optimize assessment with an explanatory emphasis; a case study is the preferred method for this research design because it inherently answers explanatory or how questions (Yin, 2009).

    Defining Functionality

    Determining communicative functionality through sensitive assessment measures is important because it allows a clinician to operationally define functionality for a specific client, and in turn, the clinician can develop a more meaningful and effective course of therapy for the client. But what is functional? Defining functionality for the purposes of therapy and third-party payers has proven to be a point of contention for clients and their service providers (Elman & Bernstein-Ellis, 1995). Although some definitions of functionality are limited to basic communicative skills, the average client would not be satisfied with only regaining basic communicative skills. An extension of the definition of functionality is necessary: A definition encompassing quality of life and considerations of premorbid functionality for the individual client is essential in optimizing therapy for the client.  

    As mentioned earlier, it is important for clinicians to characterize the pattern of subtle deficits in order to obtain a more accurate and complete picture of an individual’s communicative functionality. Since standardized testing, such as the Western Aphasia Battery (Kertesz, 1982), is unable to capture the nature of subtle deficits, clinicians must use more sensitive testing measures to characterize the deficits. One potential way to capture the underlying nature of a mild aphasia is to characterize the everyday communication of the individual, a relatively difficult task. This can be completed through examining every-day discourse.

    Narrative Discourse

    Narrative discourse is one of the basic discourse genres and is commonly referred to as storytelling (Longacre, 1996). Narrative discourse may be an ideal type of discourse to examine for everyday communicative functionality because stories are used extensively in daily conversation. When attempting to address a client’s functionality, a clinician might begin by determining if the client can achieve the essential functions that narrative discourse fills.

    One of the primary functions of a narrative is the referential function, that is the expression of the who, what, where and when of the story (Olness, Gyger, & Thomas, 2012). This study focuses on two of these, the who and the when, which differentiate narrative discourse from other discourse genres (Longacre, 1996). In discourse terminology, expression of the who fulfills the narrative parameter called agent orientation and the when fulfills the narrative parameter called contingent succession (Longacre,1996). In a story, one will naturally find mention of key characters (the who) who took part in the events being narrated. A narrative will also include mention of the events that occur, and those events will occur in a specific temporal-causal sequence. This means that the occurrence of one action is contingent upon the previous actions.

    Consider examples of the expression of the who and the when found in the following excerpt from the narrative produced by the individual studied in this case (as also found in Appendix A):

    [18]…two people in the plane were not properly belted down…

    [19] and they were lifted out of their seat…

    [22] and they pushed up against there…

    [23] and they threw back down into their seat

    These idea units specify the who: “two people…they…they…they.” The idea units also specify the when by sequencing events: “…[first] they were lifted… [then] they were pushed up…[then] they threw back down…” Each event is contingent upon the previous events; the two people could not be thrown down into their seats, unless if they were first lifted and pushed up out of their seats.

    This temporal-causal sequence is carried in what is called the storyline, while other idea units act as background or setting to the storyline (Longacre, 1996; Olness, 2006). It is essential to the analysis of the current study that verb semantics (meaning), verb morphology (units of meaning attached to the verb, such as –ing) and adverbial phrases (such as at that moment) differentiate storyline from background from setting; this will be detailed in Methods. Another important concept is that the verb semantics, morphology, and adverbials should be consistent within storyline, background and setting functions. For instance, the verb semantics of the storyline should match the adverbials and morphology characteristic of the storyline.



    The participant in this case study was a 64-year-old male who suffered four strokes within a two year time period; the fourth stroke was located in the left hemisphere language centers, resulting in aphasia. The aphasia was first diagnosed as moderate/mild in severity, which the Western Aphasia Battery (WAB) detected (Kertesz, 1982). At the time of the narrative discourse sample and interview in the current study, the aphasia had resolved to a mild aphasia, which was no longer detected by the WAB. The WAB was administered on three occasions during and after out-patient speech therapy services and confirmed both the initial diagnosis of aphasia and its apparent resolution. Refer to Figure 1.

    The participant required higher-level discourse abilities in professional contexts due to his education level and occupation. He earned his Ph.D. in thermal and mechanical engineering and founded his own company. He also reported partaking in a rich social life before the stroke, including playing in tennis clubs and social dancing.

    Despite the fact that his WAB scores were in the normal range at the time of the interview, the participant still voiced concerns over reduced functionality in day-to-day communication. He reports that pre-stroke he enjoyed conducting his business over the phone or in person, but post-stroke he would rather communicate via writing (email). The participant’s speech therapist also noted that the participant described concerns regarding restricted participation, “[the] patient voiced some residual hesitation with initiating business contacts with unfamiliar clients,” as well as activity limitations.

    Nature of the sample

    The sample of narrative discourse elicited from the participant was narrative in genre. The sample was elicited by an impartial interviewer who served as an interested listener (Labov, 1972). The interviewer asked the participant to tell a personal story about a frightening experience; the participant gave an account of time when he traveled in a small aircraft that experienced severe turbulence. As is characteristic of the narrative genre, the sample contained both active agents (the who) and contingent succession (the when).


    Since the goal of the analysis was to determine functionality, the narrative sample was analyzed on the two essential parameters that define functional narrative discourse: agent orientation and contingent succession (Longacre, 1996).

    Agent orientation. Analysis of agent orientation (the who) was based on a model of discourse cohesion, which provides an account of how references to agents in a discourse are tied to each other (Halliday & Hasan, 1976). For example, the agents (‘two people’) are referenced with a full noun form (nominal) early in the discourse and the same agents are referenced with pronouns (pronominals) later in the discourse, such as (‘they…they…they’) (refer to Appendix A, lines 19, 22, 23). Each reference to a human agent was traced from the beginning of the discourse to the end of the discourse. Each reference was judged for the clarity of its reference to a specific agent.

    Contingent succession. Contingent succession was analyzed on two dimensions: (1) temporal conjunction (Halliday & Hasan, 1976); and (2) consistency of aspect marking within each idea unit in the storyline, each idea unit in background and each idea unit in the setting of the narrative (Longacre, 1996).

    Temporal conjunction. Temporal conjunction functions as the chronological link within the narrative and between idea units (then, next, after, finally, at that moment, etc.). The narrative was analyzed for the presence of temporal conjunctions (Halliday & Hasan, 1976).

    Aspect. Aspect refers to the “completeness” of the event, activity or state, expressed in the idea unit (Leech & Svartvik, 1976). This second analysis of contingent succession was based on the premise that the backbone of a narrative (Labov, 1972) is the narrative storyline expressed in punctiliar aspect (e.g. at that moment) (Longacre, 1996). The narrative background consists of activities expressed by progressive aspect (-ing in English). The narrative setting of the story is marked by stative aspect (e.g. the verb to be in English) (Longacre, 1996). See Figure 2  for further description of aspect in storyline, background, and setting, with examples.

    Importantly, the functionality of a narrative depends on the fact that each idea unit in the narrative be marked, and consistently so, for its correct aspect:  punctiliar aspect for idea units in the storyline; progressive aspect for idea units in the background, and stative aspect for idea units in the setting.  Aspect which is incorrectly marked or inconsistently so results in a diminution of narrative functionality.  The analysis assessed whether the target aspect marking in each idea unit was correctly and consistently expressed.  For example, as defined in Leech and Svartvik (1975) punctiliar aspect may be marked in the semantics of the verb and in the adverb. Consider the following example in which marking of aspect is consistent:

    [13] And then all of a sudden the props dropped out from underneath.

    This storyline idea unit contains two markings of punctiliar aspect (denoting that the event occurred in a brief instant of time): the adverbial all of a sudden, and the semantics of the verb dropped, thus, it is correct and consistent in its aspect.

    In contrast, consider the following example in which marking of aspect is inconsistent:

    [18] At that point, one or two people in the plane were not properly belted down

    This idea unit expresses a state in stative aspect were not properly belted down with an adverbial in punctiliar aspect at that point. This demonstrates inconsistent aspect marking within the idea unit. In Appendix B, this analysis is exemplified, different aspect markings (punctiliar, progressive, stative) are denoted with different icons. Matches in aspect are denoted by an arc linking two aspect markings, while inconsistent aspect marking is denoted by an arc-with-double-slashes linking two aspect markings.

    Tense. Tense is the correspondence between the concept of time (past, present, future) and the form (morphology) of the verb in the verb phrase. Previous research has shown that the past tense is extensively used throughout the narrative, until the end of the narrative, when the tense moves into the present (Labov, 1972).   Analysis assessed whether appropriate tense was used in each idea unit of the narrative.


    Agent Orientation

    There were seven agents traced within the narrative sample, these were: the narrator, the narrator’s parents, the other passengers, the flight attendants, the pilot, a couple of individual people in the plane who were not in seatbelts, and the manufacturers of the plane. All instances of nominal and pronominal reference in the narrative clearly referred to an established agent.

    The following is an excerpt from the narrative sample illustrating clear reference to an established agent using full nominal and pronominal forms (narrator and parents). See Appendix A.

    [1] …When I was twenty…my parents had an opportunity…

    [2]  ...first leg of our flight…

    [3] …we were gonna catch a flight…

    [36] …we finally made it back…

    [38] …we were a little concerned about safety from that point on…

    Contingent Succession

    Temporal conjunction.  The participant demonstrated extensive use of temporal conjunction (refer to Appendix A), for example:

    [1] When I…   

    [2] and the first leg…

    [3] …and then go… 

    [5] About half way through

    [13] And then, all of a sudden

    [18] At that point

    [24] And at the moment

    [25] And at that moment

    [36] And then we finally

    Aspect. In eleven instances of multiple aspect marking within an idea unit, eight were consistently marked within the idea unit, and three were inconsistently marked within the idea unit. See Appendix A. Consider the following example of consistent aspect marking:

    [13] And then, all of a sudden, the props dropped out from underneath.

    In this example, punctiliar aspect in the adverbial all of a sudden is matched appropriately with punctiliar aspect in the verb phrase dropped and both fall into the category of storyline.

    Next, consider the following example of inconsistent aspect marking:  

    [25] And at that moment everybody was quiet for a second,

    [26] And then they started laughing.

    In this second example, the participant demonstrates an inconsistency between punctiliar aspect adverbials at that moment, for a second, and stative aspect in the verb phrase was quiet. It is notable that the punctiliar aspect marking in the verb phrase does not appear until the next idea unit started (laughing).


    An analysis of tense demonstrated appropriate use of verb morphology within the narrative; the participant followed the general flow of narrative from past tense (beginning and middle of narrative) to present tense (end of narrative). One notable instance of tense confusion occurred:

    [30] And to this day, I felt like hot coffee on my hand while it was spraying all over the cabin.

    This example demonstrates tense confusion between the adverbial and the verb phrase. The adverbial to this day implies the present tense, while the verb felt is in the past tense and the second verb phrase while it was spraying is also in the past tense.


    In the past, professionals in the field of speech-language and aphasiology have struggled with how to assess mild aphasia because the nature of the deficits is diagnostically elusive and difficult to capture in standardized testing. The analysis conducted for this study illuminates subtle deficits that were not previously evident through standardized aphasia testing. The participant’s Western Aphasia Battery scores were indicative of a resolved mild aphasia—refer to Figure 1—and demonstrated great improvement over time. The final administration of the WAB indicated that he no longer had aphasia, yet the analysis in this case study indicates that he indeed still exhibits aphasic symptoms. The analysis captures the subtle deficits inherent of his mild aphasia. Although his personal reference and temporal conjunction were functional, his narrative indicated a dysfunction in the use of aspect and tense.

    Finding an alternative means of sensitive assessment is paramount for individuals with mild aphasia who could greatly benefit from further services and client-tailored therapy. The functional analysis of narrative discourse that this study presents provides a more complete and accurate communicative profile of the participant then would be available through standardized assessment tools; this may be one valid and sensitive approach to assessment. Ultimately, this case contributes to the literature on means of functional assessment. Moreover, this case study provides an approach to sensitive assessment that addresses functionality in every-day communicative contexts, as opposed to standardized assessment that serves only as a decontextualized measure of impairment.

    Since this analysis evidences the manifestations of subtle deficits in the participant, it is now possible to characterize the subtle deficits. Characterizing these subtle deficits is not only important in functional assessment, but also in designing tailored therapy for clients. Attempting to create a therapy plan without a characterization of deficits would be similar to building a house without a blueprint. As is observed, the deficits are manifested in the participant’s ability to express aspect within temporal contexts and narrative structure. It is hypothesized that the participant may be experiencing sequencing disruptions of narrative functions in his utterances. Previously, the participant stated, “I have issues with sequencing…my mind [is like] a pipeline…it’s like putting different colored balls in a pipe, they come out the end of the pipe, I remember the colors that went into the pipe, but now I have to remember the sequence.” It is reasonable to assume that these reported sequencing disruptions could also be manifested at the level of narrative dimensions such as aspect and tense marking. A functional therapy plan could address this disruption with a variety of therapeutic tools, for example, the clinician could ask the client to match aspect within sample utterances. Without knowing the deficit, the clinician would not maximize her therapeutic tools, or may use tools that do not address the deficit at all.

    This type of analysis may also aid clinicians in seeking out further funding from third-party payers for speech-language services. Clients with mild aphasia, and especially those who have high demands for functional communication, often voice concerns about communicative functionality, but are denied therapeutic speech services (Elman & Bernstein-Ellis, 1995). One reason for this is because third-party payers will not continue to pay for services for clients who score high or normally on standardized testing, and reasonably so. Advocacy for clients is one of the very important roles of clinicians in the speech-language therapy field. Presenting viable measures of sensitive assessment that justify provision of services as well as providing well-constructed and functional therapy plans could be enough compelling evidence to warrant further funding from third-party payers.

    The future of applied research in this area will yield great results for clients with aphasia, one clinical researcher has commented,

    The field can be encouraged that models of functional communication can serve as a foundation for the design of assessments tailored to a variety of clinical situations and that measures need not be quantitate or time-consuming to meet rigorous standards of validity and reliability. Already, researchers and clinicians alike can envision a future in which feasible and valid assessments of communicative effectiveness become a clinical reality. (Olness et al., 2012)


    • Elman, R.J., & Bernstein-Ellis, E., (1995). What is functional?. American Journal of Speech-Language Pathology, 4, 115-117.
    • Halliday, M., & Hasan, R. (1976). Cohesion in English. London: Longman Group Limited.
    • Kertesz, A. (1982). The Western Aphasia Battery. Austin, TX: Pro-Ed.
    • Labov, W. (1997). Some further steps in narrative analysis. Journal of Narrative and Life History, 7, 395-415.
    • Leech, G., & Svartvik, J. (1975). A communicative grammar of English. Burnt Hill, United Kingdom: Longman.
    • Longacre, R. E. (1989). Two hypotheses regarding text generation and analysis. Discourse Processes, 12, 413-460.
    • Longacre, R. E. (1996). The grammar of discourse (2nd ed.). New York: Plenum Press.
    • National aphasia association. In (2009). National Aphasia Association. Retrieved from Facts/aphasia_faq.html
    • Olness, G.S. (2006). Genre, verb, and coherence in picture-elicited discourse of adults with aphasia. Aphasiology, 20, 175-187. doi:10.1080/02687030500472710
    • Olness, G.S., Gyger, J., & Thomas, K. (2012). Analysis of narrative functionality: Toward evidence-based approaches in managed care setting. Seminars in Speech and Language (Special Issue – Discourse Across Disorders: Acquired Neurogenic Conditions), 33, 55-67. doi:10.1055/s-0031-1301163
    • Yin, R. K. (2009). Case study research, design and methods (4th ed.). Thousand Oaks, CA: Sage.

    Figure 1: Western Aphasia Battery: Subtest Scoring Over Time for C-APH01

    Figure 2: Salience scheme adapted from Longacre (1989, 1996) and Olness (2006)




    Visual Aspect Marking





    Punctiliar, sequential happenings in text world. Action, motion, and events (cognitive or otherwise), often marked with punctiliar adverbs






    [13] “And then, all of the sudden, the props dropped out from underneath.” [14] “And the plane just went straight down.”


    Non-punctiliar, non-sequential activities and states, often expressed in progressive aspect, often atelic, sometimes marked with durative adverbs



    [16] “I mean, we were coming up out of the seat, up, up against our seatbelts.”


    Introduces participants and props and localizes the text in time and space. Expressed by statives with “be”, descriptive, equatives, existential/locational and relational clauses. Also expressed through verbs with inanimate objects


    [37] “And from that point on we were a little concerned about safety”



    Appendix A: Narrative Produced in Response to Frightening Experience Prompt

    [1] When I was age twenty, let's see, eighteen, nineteen, twenty. Age twenty. Uh, my Parents had an opportunity to go to Europe. (Interviewer: hmm.) [2] And the first leg of our flight was going, from DFW not DFW Love… at Love Field to Washington. [3] And we were gonna catch a flight from Washington to LaGuardia, and then go trans, transaklantic flight overl to Paris Le Bourget Airport.(Interviewer: mmhm, mmhm) The old French airport. (Interviewer: hmm.) [4] So here we are taking off from Love Field in a turbo jet. (Interviewer: hmm.) Uh, I'm trying to remember exactly what time is, af, a four engine turbo jet aiming up toward Washington D.C.  [5] About half way through the flight uh…severe weather. [6] And we were at full altitude, probably twenty five thousand feet. [7] And, uh, lightning…black clouds all around us. [8] And we were just t-totally enveloped in this whole thing. [9] (Interviewer: oh my gosh oh my gosh.) And the whole plane totalling up and tipping to the left, to the right. [10] And we were, uh, obviously alarmed with the seatbelts. [11] Put us in seatbelts. [12] And so we're just going on like a rollercoaster for two or three minutes. [13] And then, all of a sudden, the props dropped out from underneath. [14] And the plane just went straight down. [15] We felt like were down for, completely falling for a minute. [16] I mean we were coming up out of the seat, up, up against our seatbelts. For it seemed like a minute [17] it was probably more like ten or twenty seconds. [18] (Interviewer: oh! oh!) At that point, one or two people in the plane were not properly belted down [19] and they were lifted out of their seat into the, overpass, overhead luggage rack. [20] Now they don't do that on the planes now [21] but they used to have a luggage rack over. [22] (Interviewer: uh huh.) And they pushed up against there for probably five or ten seconds [23] and they threw back down into their seat. [24] (Interviewer gasps) And at the moment the pa, pai, the pilot had taken us down underneath uh the bad weather into calm weather. [25] (Interviewer:  oh my gosh.) And at that moment everybody was quiet for a second, [26] and then they started laughing. [27] (Interviewer laughs) (Interviewer: oh gosh.) One of the things that, that happened during that is the flight attendants did not realize the quick, uh, change into the rough air [26] and they were making coffee. [28] They were taking coffee cups down. [29] And the coff-ee, coffee went everywhere, ceiling to the… [30] And to this day, I felt like hot coffee on my hand while it was spraying all over the cabin. [31] (Interviewer: oh my gosh oh my gosh.) It was Braniff Airline. [32] I'm trying remember what the airplane was called. [33] It was a turbo top, turbo prop plane. (Interviewer: oh my gosh.) [34] So we had a little laughter to, to break the uh silence. [35] (Interviewer: Yeah. No kidding. No kidding.) [36] And then we finally made it back to Washington D.C. [37] Uh, changed planes. [38] (Interviewer: hmm.) And from that point on we were a little concerned about safety from that point on all the way over to Paris. [39] (Interviewer: No kidding, no kidding. Yeah no kidding.) And that was probably about the second time I'd ever been on an airplane. (Interviewer: oh my gosh.) Second or third time flying. [40] True story.

    Appendix B: Narrative Sample Showing Analysis of Aspect Matching Between Adverbial Phrases and Verbs

    See Table 1 for aspect marking key.