**5. Discussion**

than the P25, while 80% of the TSP (12/15) has a score equal or less than the P25 (results available upon request).] As shown, the presence of TS for the E&T indicators (individually considered) appeared as a rather nonspecific factor in terms of the stimuli involved, that is, TS was not related to a certain modality of cognitive impairment such as the verbal

Additionally, and given that the representative measure of DP also produced a significant difference between TSP and both non-TSP and HP, its individual indicators were analyzed. The MANOVA with TS as grouping variable and the indicators of DP as dependent variables indicated that all the dependent variables produced a significant effect on the multivariate measure of performance (Wilks Lambda = 0.52, F (12, 334) = 10.71, p < 0.0001). A main effect of TS was produced on all the components of the model except for the interviewer's global impression during administration of the cued story recall (all significant univariate effects: F (2, 172) ≥ 8.78, p < 0.0002; the non-significant univariate effect: F (2, 172) = 1.48, p = 0.2305). When pairwise comparisons were analyzed, non-TSP and TSP did not differ in the standardized and detailed scoring of the 25 passages after administration of the cued story recall (Bonferroni post-hoc test: p = 0.3179) but they did differ in the rest of the components (Bonferroni post-hoc tests: non-TSP vs. TSP all p ≤ 0.0220). Considering HP, significant differences between HP and TSP were observed in any of the univariate measures, excluding cued recall (Bonferroni post-hoc tests: HP vs. TSP all p < 0.0001). Therefore, not all the indicators of DP, individually considered, produced significant differences between non-TSP and TSP as it can be inferred from the cued recall in its both indicators. [Note: all univariate results described in the present study were confirmed with nonparametric tests (results available

Regarding inter-rater reliability, the ICC was 0.86 without difference between both raters according to the Wilcoxon paired-sample test (z = 0.00, N = 95, p = 1). [Note: the ICC for the dichotomized TS scale was 0.79 [Wilcoxon paired-sample test (z = 0.40, N = 95, p = 0.685)].

Present results support the hypothesis that the emergence of TS (with a prevalence of 16% in this sample) not only may be a consequence of focal brain lesions, of any type or site, but also is associated with cognitive impairment. TSP showed, as a whole, an impaired GNP relative to non-TSP and HP. The implication of TS on cognition was more related to E&T, rather than to CR, that is, although both CR and E&T contributed with the differences observed in GNP, when the two components of performance were differentiated, E&T were significantly associated with TS whereas CR were not. Alternatively, the tasks of the battery related with DP were significantly associated with TS whereas the tasks related with verbal fluency were not. More detailed analyses carried out to discover the cognitive nature of the TS correlates, indicated that the effect of TS on E&T involved tasks of different modality such as verbal and nonverbal sustained attention and attention (orientation)

or the nonverbal one.

206 Gerontology

upon request)].

**4. Conclusion**

In the most recent research on verbal communication, AbdulSabur et al. [8] and Awad et al. [40] analyzed the processes involved in sharing knowledge through narrative processing, and described extended brain networks and bilateral involvement in their neurofunctional studies with healthy participants. Consistent with this view, Jouen et al. [5] observed in a combined fMRI and DTI study with healthy participants that understanding sentences and pictures revealed bilateral involvement and a common fronto-temporo-parietal network for both modalities. This semantic network was not limited to sensorimotor systems but extended to the highest levels of cognition, including autobiographical memory, scene analysis, mental model formation, reasoning and theory of mind. Present results agree with those studies since no focal brain lesions were identified for TS. To be precise, present results agree with the hypothesis that this neurogenic inability to spontaneously find, organize and communicate verbal information for a specific topic, and beyond single words, may be caused by several sites of brain damage or, most probably, by aberrant interactions within extended brain networks.

In trying to understand how TS is integrated with the rest of the cognitive functions, present results indicated that TSP showed an overall impaired cognitive performance relative to non-TSP; however, the contribution of the GNP components of E&T and CR showed distinctive patterns: the relative weight of E&T was superior to that observed in CR, thus finally producing a significant effect only on E&T. More thorough analyses carried out to discover the nature of the cognitive impairments associated with TS provided illustrative results: by considering just those individual indicators of E&T related to sustained attention, which were significantly associated with TS, it can be noticed that one task involved verbal auditory stimuli and the other task involved nonverbal visual stimuli; besides, one task involved number of errors and the other task involved the time for solving the task. Therefore, neither the type of stimulus nor the type of failure seemed to be relevant to this finding. Additionally, and bearing in mind that tests of sustained attention are characterized by being monotonous and simple, some interviewees may be tempted to think that such type of tasks can be carried out with minimal effort, which may increase E&T. Nevertheless, such type of tasks only increased E&T in TSP regarding non-TSP. The errors in the time of day were also significantly associated with TS. Given that these errors not only involve other type of stimulus, but they also may be seen as a failure of sustained attention,<sup>4</sup> the nature of the significant TS impairments in E&T (and sustained attention) as a whole appeared to be independent of the type of the stimulus. In this context, it can be speculated that TS impairments in E&T may have insidiously influenced all type of tasks, although only some of those tasks showed significant impairments. (In passing, and methodologically speaking, present results highlight the need of assessing the presence and magnitude of the E&T; otherwise, valuable information can be lost. Likewise, an increased time to respond correctly, which may sometimes be a subtle difficulty (see, e.g., [58]) could represent relevant data to be assessed, as indicated by the results obtained in the E&T in general, and in the T of nonverbal sustained attention, in particular).

from 'knowing the correct response', as inferred from CR, to the final result can be delayed

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Franklin et al. [59] assessed lapses of attention (mind-wandering) with experience-sampling thought probes during a standard implicit learning, in a serial reaction time task. Their results revealed an adverse effect of mind-wandering on implicit learning. Such results would be in agreement with the present ones because TSP, who had lower scores on tasks of sustained attention, also showed an impaired implicit learning in story recall with regard

It is currently accepted that when automatic tasks are carried out, other cognitive and emotional associations are more prone to be spontaneously processed in the form of, for example, mind-wandering (see [59–61]). Since in the present study, TS was associated with automatic and complex linguistic tasks, it can be hypothesized that TS is an exacerbated manifestation of mind-wandering linked to high-level and verbal cognitive impairment. As verbal language interacts with the rest of the cognitive and behavioral functions thus helping to voluntarily organize thoughts and actions of any kind, dysfunctions in this domain can seriously affect many other skills [62]. What is more, the left inferior frontal gyrus involved in inner speech [63], which is an essential part of the executive-control language network, has been related to

In addition, and considering just the two groups of patients, TS was associated with emotional and behavioral alterations. Although there were no patients who showed aggression, hallucinations or delusions during the administration of the battery, there was an association between TS and either the behavioral and thought disturbances as perceived by the caregiver<sup>5</sup> or the presence of diminished cooperation, emotional excitement and rapid speech as regis-

Within this context, it is worth mentioning that, although language speed was found to be higher in TSP than in non-TSP, both groups of patients did not differ in spoken and written verbal fluency tests. This finding suggests that the clinical interpretation of rapid speech in TSP was probably produced by the presence of many irrelevant words during a certain period of observation. Furthermore, the interaction of TS with diminished cooperation, or emotional excitement, may have as well affected the outcome: the process of selecting (finding and pondering) the correct verbal information to be expressed, necessarily involves an inhibitory adjustment, as only some parts of the total thoughts linked to the target topic will be expressed. If the emotional balance between excitatory and inhibitory mechanisms is affected, the cognitive organization which goes from nonspecific/divergent utterances to specific/convergent ones may be obstructed. Alternatively, tests of fluency, unlike spontaneous speech, are required to follow certain constraints, which may have prevented TSP from communicating irrelevant information (compared with the relevant one) during such tasks. So, it seems

When the semantics and syntax in a sentence do not represent a problem, as in the case of nonaphasic patients, that is, when the ability to use, understand or connect words is not impaired, then impairments in the semantics and (high-

level) 'syntax' in a narrative, can be interpreted as a manifestation of thought (see, e.g., [17]).

the monitoring of self-generated thoughts and divergent thinking [60].

or obstructed with errors.

tered by the neuropsychologist.

5

to non-TSP.

On the other hand, the individual indicators of DP that produced a significant difference between non-TSP and TSP were: (a) syntax-complex verbal comprehension; (b) reading a story: abstraction/comprehension and (c) a delayed (and spontaneous) story recall. So, it can be stated that TS was also associated with high-level and/or complex linguistic tasks involving processes such as verbal comprehension, attention and memory. Regarding this finding, it can be relatively understood that if patients have problems to narrate an event (e.g., the reason for consultation), they can also have problems to narrate other event (e.g., the story involved in DP). The nature of the cognitive demands involved in this particular task of story recall, however, provide additional information in relation to the factors which were combined with the narration itself: specifically, the items (b) and (c) involved implicit attention and memory, that is, those tasks were intentionally designed to be effortlessly or automatically carried out by leaving them unprompted. For example, the comprehension and recall of a story were both included as components to a series of reading tasks, in which the command was just 'read' (neither 'think about what you read' nor 'remember what you read'). Therefore the cognitive demands of interpreting and later recalling a story required that the information be spontaneously registered and organized by the interviewee. By integrating these findings with those described above concerning sustained attention, it can be observed that most of the individual tasks associated with TS required a high degree of spontaneous (unassisted/self-controlled) organization. If failures in cognitive engagement interfere with such organization, then the appearance of irrelevant commentaries or taskunrelated thoughts (mind-wandering) could be favored. In this way, it is probable that E&T increase and the final performance (GNP) decrease. In other words, the process that goes

<sup>4</sup> If the time of day is seen as the target stimulus, and the ability to maintain focused awareness on it during continuous period is seen as the attention task condition, then paying attention to the time of day is a form of sustained attention.

from 'knowing the correct response', as inferred from CR, to the final result can be delayed or obstructed with errors.

task involved number of errors and the other task involved the time for solving the task. Therefore, neither the type of stimulus nor the type of failure seemed to be relevant to this finding. Additionally, and bearing in mind that tests of sustained attention are characterized by being monotonous and simple, some interviewees may be tempted to think that such type of tasks can be carried out with minimal effort, which may increase E&T. Nevertheless, such type of tasks only increased E&T in TSP regarding non-TSP. The errors in the time of day were also significantly associated with TS. Given that these errors not only involve other

the significant TS impairments in E&T (and sustained attention) as a whole appeared to be independent of the type of the stimulus. In this context, it can be speculated that TS impairments in E&T may have insidiously influenced all type of tasks, although only some of those tasks showed significant impairments. (In passing, and methodologically speaking, present results highlight the need of assessing the presence and magnitude of the E&T; otherwise, valuable information can be lost. Likewise, an increased time to respond correctly, which may sometimes be a subtle difficulty (see, e.g., [58]) could represent relevant data to be assessed, as indicated by the results obtained in the E&T in general, and in the T of nonver-

On the other hand, the individual indicators of DP that produced a significant difference between non-TSP and TSP were: (a) syntax-complex verbal comprehension; (b) reading a story: abstraction/comprehension and (c) a delayed (and spontaneous) story recall. So, it can be stated that TS was also associated with high-level and/or complex linguistic tasks involving processes such as verbal comprehension, attention and memory. Regarding this finding, it can be relatively understood that if patients have problems to narrate an event (e.g., the reason for consultation), they can also have problems to narrate other event (e.g., the story involved in DP). The nature of the cognitive demands involved in this particular task of story recall, however, provide additional information in relation to the factors which were combined with the narration itself: specifically, the items (b) and (c) involved implicit attention and memory, that is, those tasks were intentionally designed to be effortlessly or automatically carried out by leaving them unprompted. For example, the comprehension and recall of a story were both included as components to a series of reading tasks, in which the command was just 'read' (neither 'think about what you read' nor 'remember what you read'). Therefore the cognitive demands of interpreting and later recalling a story required that the information be spontaneously registered and organized by the interviewee. By integrating these findings with those described above concerning sustained attention, it can be observed that most of the individual tasks associated with TS required a high degree of spontaneous (unassisted/self-controlled) organization. If failures in cognitive engagement interfere with such organization, then the appearance of irrelevant commentaries or taskunrelated thoughts (mind-wandering) could be favored. In this way, it is probable that E&T increase and the final performance (GNP) decrease. In other words, the process that goes

If the time of day is seen as the target stimulus, and the ability to maintain focused awareness on it during continuous period is seen as the attention task condition, then paying attention to the time of day is a form of sustained attention.

the nature of

type of stimulus, but they also may be seen as a failure of sustained attention,<sup>4</sup>

bal sustained attention, in particular).

208 Gerontology

4

Franklin et al. [59] assessed lapses of attention (mind-wandering) with experience-sampling thought probes during a standard implicit learning, in a serial reaction time task. Their results revealed an adverse effect of mind-wandering on implicit learning. Such results would be in agreement with the present ones because TSP, who had lower scores on tasks of sustained attention, also showed an impaired implicit learning in story recall with regard to non-TSP.

It is currently accepted that when automatic tasks are carried out, other cognitive and emotional associations are more prone to be spontaneously processed in the form of, for example, mind-wandering (see [59–61]). Since in the present study, TS was associated with automatic and complex linguistic tasks, it can be hypothesized that TS is an exacerbated manifestation of mind-wandering linked to high-level and verbal cognitive impairment. As verbal language interacts with the rest of the cognitive and behavioral functions thus helping to voluntarily organize thoughts and actions of any kind, dysfunctions in this domain can seriously affect many other skills [62]. What is more, the left inferior frontal gyrus involved in inner speech [63], which is an essential part of the executive-control language network, has been related to the monitoring of self-generated thoughts and divergent thinking [60].

In addition, and considering just the two groups of patients, TS was associated with emotional and behavioral alterations. Although there were no patients who showed aggression, hallucinations or delusions during the administration of the battery, there was an association between TS and either the behavioral and thought disturbances as perceived by the caregiver<sup>5</sup> or the presence of diminished cooperation, emotional excitement and rapid speech as registered by the neuropsychologist.

Within this context, it is worth mentioning that, although language speed was found to be higher in TSP than in non-TSP, both groups of patients did not differ in spoken and written verbal fluency tests. This finding suggests that the clinical interpretation of rapid speech in TSP was probably produced by the presence of many irrelevant words during a certain period of observation. Furthermore, the interaction of TS with diminished cooperation, or emotional excitement, may have as well affected the outcome: the process of selecting (finding and pondering) the correct verbal information to be expressed, necessarily involves an inhibitory adjustment, as only some parts of the total thoughts linked to the target topic will be expressed. If the emotional balance between excitatory and inhibitory mechanisms is affected, the cognitive organization which goes from nonspecific/divergent utterances to specific/convergent ones may be obstructed. Alternatively, tests of fluency, unlike spontaneous speech, are required to follow certain constraints, which may have prevented TSP from communicating irrelevant information (compared with the relevant one) during such tasks. So, it seems

<sup>5</sup> When the semantics and syntax in a sentence do not represent a problem, as in the case of nonaphasic patients, that is, when the ability to use, understand or connect words is not impaired, then impairments in the semantics and (highlevel) 'syntax' in a narrative, can be interpreted as a manifestation of thought (see, e.g., [17]).

that both the type of task constraints and the cognitive engagement to effectively prioritize between competing internal and external demands [64] were implicated in TS.

in executive function compared with non-TSP. In line with this notion, Barbey et al. [9] suggest that core elements of discourse processing emerge from a distributed network of brain regions that support specific competencies for executive, social and emotional processes

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On the other hand, sustained attention [69], discourse abilities [8] and internally oriented mental processes such as: autobiographical memory; theory of mind; self-referential processing; future thinking and scene construction [60, 74], that is, the retrieval and integration of elements of previous experiences into a coherent event [74], have been related to the default mode network. Since all these cognitive processes are comprised in the spontaneous (selfreferential) speech by which patients describe their own disease, the link between TS and the

In summary, this work highlights the importance of studying a single and comprehensive item, that is, spontaneous speech, thus emphasizing the registration of one of its pathological expressions. As demonstrated here, TS was related to illness, to a neurogenic cognitive and behavioral disorder which, apparently, comprised a distributed brain network. Understanding the psychobiological correlates of TS may result in better strategies for interpreting such a disorder, in particular, to avoid errors in clinical practice. Since TS may be a non-trivial feature, its early detection is advisable for prevention and treatment: in the same way as finding and organizing words are essential points to be analyzed in the aphasic component of spontaneous speech, finding and organizing topics are essential points to be analyzed in the discourse component of spontaneous speech. People who show the failures associated with TS, even if those failures are subtle or insidious (like an increase in the frequency of apparently harmless lapses, interruptions of sustained attention, increased time to respond correctly, difficulty understanding or expressing complex texts, inability to (implicitly) attend and recall recent conversations, along with emotional and behavioral changes), may be suffering of a neurogenic disorder, with implications in global cognition and high-level language processing. If those failures are not early detected and treated, they

The combination of failures in selective and sustained attention along with the special characteristics of the language impairments observed in this study, allowed to outline a hypothetical pattern of cognitive symptoms associated with TS to be verified in further research. The association between TS and recognized measures of discourse processing, namely, complex verbal comprehension and story recall/storytelling, provided support for the viability and validity of the present TS screening scale, which was also reliable between

By using efficient scales, aphasia and TS could be simultaneously screened during the first step of the doctor-patient interview. In this work, one complex function was assessed with a simple but carefully designed scale, which facilitates both saving time and controlling intervening variables during the interview interaction. The property of saving time during neuropsychological language evaluations is valuable, particularly in public hospitals. Additionally,

(see also [69–73]).

default mode network cannot be discarded either.

may evolve to a more serious condition.

raters.

The interaction among emotional, behavioral and verbal language functions may have also influenced present anatomical results. The ability to deliberately stop intrusive thoughts and pay attention to the context, the relevant goal and the interviewer's signals (verbal and nonverbal) pertains to the more encompassing function of communication and social interaction. Kuhlen et al. [65] affirm that, for successful communication, conversational partners need to estimate each other's current knowledge state. These authors observed that nonverbal facial and bodily cues can reveal relevant information for such knowledge and also proposed that an integrative account of the mirroring and mentalizing networks can explain their results. Accordingly, Prochnow et al. [66] found that both supra- and subliminal emotional facial expressions shared a widespread network of brain areas, many of which have been implicated in empathy and social encounters. Since emotional and behavioral disturbances were observed in TSP, including nonverbal social processes, a disruption of distributed brain networks concerning such processes is conceivable for these patients.

The psychiatric and/or cognitive disorders that have been linked to TS also involve complex brain functions and networks. For example, and considering the implications for understanding the functional neuroanatomy of bipolar disorder, Satzer and Bond [67] observed in their review about mania and focal brain lesions that mania occurs most commonly with lesions affecting frontal, temporal and limbic-brain areas: bilateral prefrontal emotion-modulating regions and a probable imbalance between left-sided excitatory and right-sided limbicbrain inhibitory lesions have been proposed to understand the pathophysiology of mania. Considering the functional relationship between language and mood disorders, Cuesta and Peralta [68] observed that disorganization was the main language dimension accounting for the broader construct of formal thought disorder [2], which is usually studied in patients with psychiatric disorders.<sup>6</sup> Taken together, these studies underline a relationship among disorganization of language, emotional disturbances and a disruption of distributed brain networks, agreeing with the present anatomical results.

Another psychiatric disorder that has been linked to TS is schizophrenia. Under this background, and also related to the concepts of disorganization of language and formal thought disorder, Holshausen et al. [23] hypothesize that executive functioning may play a role in maintaining the topic of conversation, planning upcoming speech and inhibiting inappropriate or unrelated discourse. (The authors also suggest employing a neurocognitive battery to elucidate this question in further studies.) Given that, in the present study, TSP and non-TSP showed differences in global cognition, and that global cognition and executive functioning are closely related [49, 56], it cannot be discarded that TSP showed impairment

<sup>6</sup> A radical difference between the psychiatric approach and the present one is that the construct of formal thought disorder and, particularly, its subcomponent of disconnected or disorganized speech include incoherence below the level of the sentence. These two different levels of analysis may lead to discover different levels of linguistic impairment.

in executive function compared with non-TSP. In line with this notion, Barbey et al. [9] suggest that core elements of discourse processing emerge from a distributed network of brain regions that support specific competencies for executive, social and emotional processes (see also [69–73]).

that both the type of task constraints and the cognitive engagement to effectively prioritize

The interaction among emotional, behavioral and verbal language functions may have also influenced present anatomical results. The ability to deliberately stop intrusive thoughts and pay attention to the context, the relevant goal and the interviewer's signals (verbal and nonverbal) pertains to the more encompassing function of communication and social interaction. Kuhlen et al. [65] affirm that, for successful communication, conversational partners need to estimate each other's current knowledge state. These authors observed that nonverbal facial and bodily cues can reveal relevant information for such knowledge and also proposed that an integrative account of the mirroring and mentalizing networks can explain their results. Accordingly, Prochnow et al. [66] found that both supra- and subliminal emotional facial expressions shared a widespread network of brain areas, many of which have been implicated in empathy and social encounters. Since emotional and behavioral disturbances were observed in TSP, including nonverbal social processes, a disruption of distributed brain networks concerning such processes is conceivable for these

The psychiatric and/or cognitive disorders that have been linked to TS also involve complex brain functions and networks. For example, and considering the implications for understanding the functional neuroanatomy of bipolar disorder, Satzer and Bond [67] observed in their review about mania and focal brain lesions that mania occurs most commonly with lesions affecting frontal, temporal and limbic-brain areas: bilateral prefrontal emotion-modulating regions and a probable imbalance between left-sided excitatory and right-sided limbicbrain inhibitory lesions have been proposed to understand the pathophysiology of mania. Considering the functional relationship between language and mood disorders, Cuesta and Peralta [68] observed that disorganization was the main language dimension accounting for the broader construct of formal thought disorder [2], which is usually studied in patients with

nization of language, emotional disturbances and a disruption of distributed brain networks,

Another psychiatric disorder that has been linked to TS is schizophrenia. Under this background, and also related to the concepts of disorganization of language and formal thought disorder, Holshausen et al. [23] hypothesize that executive functioning may play a role in maintaining the topic of conversation, planning upcoming speech and inhibiting inappropriate or unrelated discourse. (The authors also suggest employing a neurocognitive battery to elucidate this question in further studies.) Given that, in the present study, TSP and non-TSP showed differences in global cognition, and that global cognition and executive functioning are closely related [49, 56], it cannot be discarded that TSP showed impairment

A radical difference between the psychiatric approach and the present one is that the construct of formal thought disorder and, particularly, its subcomponent of disconnected or disorganized speech include incoherence below the level of the sentence. These two different levels of analysis may lead to discover different levels of linguistic impairment.

Taken together, these studies underline a relationship among disorga-

between competing internal and external demands [64] were implicated in TS.

patients.

210 Gerontology

psychiatric disorders.<sup>6</sup>

6

agreeing with the present anatomical results.

On the other hand, sustained attention [69], discourse abilities [8] and internally oriented mental processes such as: autobiographical memory; theory of mind; self-referential processing; future thinking and scene construction [60, 74], that is, the retrieval and integration of elements of previous experiences into a coherent event [74], have been related to the default mode network. Since all these cognitive processes are comprised in the spontaneous (selfreferential) speech by which patients describe their own disease, the link between TS and the default mode network cannot be discarded either.

In summary, this work highlights the importance of studying a single and comprehensive item, that is, spontaneous speech, thus emphasizing the registration of one of its pathological expressions. As demonstrated here, TS was related to illness, to a neurogenic cognitive and behavioral disorder which, apparently, comprised a distributed brain network. Understanding the psychobiological correlates of TS may result in better strategies for interpreting such a disorder, in particular, to avoid errors in clinical practice. Since TS may be a non-trivial feature, its early detection is advisable for prevention and treatment: in the same way as finding and organizing words are essential points to be analyzed in the aphasic component of spontaneous speech, finding and organizing topics are essential points to be analyzed in the discourse component of spontaneous speech. People who show the failures associated with TS, even if those failures are subtle or insidious (like an increase in the frequency of apparently harmless lapses, interruptions of sustained attention, increased time to respond correctly, difficulty understanding or expressing complex texts, inability to (implicitly) attend and recall recent conversations, along with emotional and behavioral changes), may be suffering of a neurogenic disorder, with implications in global cognition and high-level language processing. If those failures are not early detected and treated, they may evolve to a more serious condition.

The combination of failures in selective and sustained attention along with the special characteristics of the language impairments observed in this study, allowed to outline a hypothetical pattern of cognitive symptoms associated with TS to be verified in further research. The association between TS and recognized measures of discourse processing, namely, complex verbal comprehension and story recall/storytelling, provided support for the viability and validity of the present TS screening scale, which was also reliable between raters.

By using efficient scales, aphasia and TS could be simultaneously screened during the first step of the doctor-patient interview. In this work, one complex function was assessed with a simple but carefully designed scale, which facilitates both saving time and controlling intervening variables during the interview interaction. The property of saving time during neuropsychological language evaluations is valuable, particularly in public hospitals. Additionally, the structure of evaluation proposed here for TS might serve as a model to be totally or partially applied to other conversational items, or even to other scientific disciplines interested in discourse processing and cognition. Since aging is a factor associated with cognitive impairment and cognitive impairment is a factor associated with TS, the presence of TS in the elderly must not be ignored.

[4] Hagoort P, Indefrey P. The neurobiology of language beyond single words. Annual Review of Neuroscience. 2014;**37**:347-362. DOI: 10.1146/annurev-neuro-071013-013847

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