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Clinical linguistics can be defined as the application of the theories, methods and findings of linguistics (including phonetics) to the study of those situations where all language handicaps are diagnosed and treated. But also, as the study of the many ways the unique capacity for language can be disordered: language disorders, disorders that result from the disruption to the wider processes of language transmission and reception, disorders of the vegetative functions that are an evolutionary precursor to language. It's an area of practice because it understands the needs of patients to tailor interventions, not to deliver them (which is the job of speech specialists...). When we look at language, we should also consider other mere vegetative functions of the human body such as eating, breathing and swallowing. Speaking is much more complex than we think. In fact, in the US 1 in 12 children ages 3-17 has had a disorder related to voice, speech, language or swallowing. Developmental language disorders are reported approximately 1 in 14 children. Also, 2% children with a language disorder have an existing medical condition such as autism or intellectual disability. 3.3% of US children ages 3-17 have a language disorder that lasted for a week or longer. About 2 million people in the US currently have aphasia, and even though everyone can get aphasia, most people who do are in their middle to late years (men and women are equally affected). Aphasia = a loss of the ability to use or understand language → it’s quite common and it has a socio-economic burden because the people suffering from it need to be taken care of. Language as a cerebral road trip = language starts in the brain, which is important to highlight because speaking requires though genesis, language encoding, motor programming, motor execution… all aspects that can be difficult or even impossible for people with different disorders or conditions. We cannot explain language as a code model but rather through assumptions (based on the context) because of the complexity of the communication process between hearer and speaker. COMMUNICATION PROCESSES COMMUNICATION DISORDER Communicative intension Problems formulating and establishing communicative intensions. It is associated with psychotic disorders (schizophrenia), mental retardation (Down’s syndrome), autism and dementia (Alzheimer’s disease). Language encoding and decoding Problems formulating and understanding various levels of language. Disorders include acquired aphasia and phonological disorder, specific language impairment and pragmatic language impairment in children. Motor programming Apraxia, both developmental and acquired Motor execution Disorders of speech production. Includes dysarthria (developmental and acquired), disorders related to articulation, phonation, resonation and fluency. Also includes
related disorders of swallowing and drooling. Sensory processing Hearing disorders (conductive and sensorineural deafness) and oral sensory dysfunction. Perception Agnosia. It affects also different sensory modalities, resulting in auditory agnosia, visual agnosia etc… The process of communication goes beyond the linguistic envelop of messages, since we have to take into consideration also extra-, para- and non-verbal linguistic communication. Linguistic communication is geared toward exchange of information, i.e. changing the addressee’s world views so we use language also for other purposes. We send information by:
- The tone of voice
- Facial expressions
- Gestures
- Body language How much time does it take? → the average reaction from seeing a picture to beginning the naming of it has been estimated at 600ms (for multiword utterances the effect is not linear). We also need to take into account that we breath during all these activities: just to plan to breath, it takes a person 200ms, then 500ms of inhalation. Therefore, to plan an utterance 700/800ms are needed every time. Conversation also includes taking turns, with overlaps and pauses so it is a mutual process that is not predictable. 75% of between interlocutors’ turns are faster than 374ms. In a way, linguistic events are slower than response in interactions. To decode what is being said by the other interlocutor and to response after, we use expressive and receptive language domain skills that pertain to morpho-syntax, prosody, pragmatics, phonology and vocabulary. Structures of the brain (left and right hemispheres):
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobe
- Cerebellum
- Brainstem To study the brain, we use fMRI which creates images of the brain from the axial, sagittal and coronal view. The basic conceptual unit of the brain is the neuron, which creates connections with other neurons through axons, agglomerates that protect the message, so it moves faster. The brain is composed of two types of matter: grey and white. The cortex is also called grey matter which is folded in budges called giry (gyrus) that creates fissures called sulci (they make 2/3 of the cortex). White matter is what glues subcortical tissue, covered in myelin aka tracts. The brain runs on blood and oxygen through veins and nerves.
opercularis). The symptoms are agrammatism especially with closed class words and compromised repetitions, but rather good comprehension. According to these early studies, the loss of functions in an area must be connected with the loss of another ability. Broca’s area is the place where language production happens (anatomy-clinical method). Broca is also famous for another one of his patients, Lelong, who was able to utter approximately 5 words because the damage was slightly different in location. Karl Wernicke (1848-1905), inspired by Broca, studied receptive aphasia which now goes after his name. this type of aphasia is also called sensory because the speech is fluent but kind of disordered: impaired understanding of speech, silent reading and sentence repetition. The damage is located in the left temporal lobe. Therefore, Broca’s area must be the centre for the representation of words and the actual movements, while temporal areas are responsible for the association between word and meaning. The fibres between the two regions are mediators of the psychic reflex arc between the heard and spoken word. Wernicke hypothesized a connection between Broca’s and Wernicke’s areas, describing the first neuroanatomical model of language. Wernicke considered the connection between areas necessary for repetitions: first. Read in and store a message. Second, re-produce it. Three possible types of aphasia:
- Broca – frontal
- Wernicke – temporal
- Lesion of the hypothetical pathways linking the word sound centre to the centres for tactile and optical memory images, which Wernicke deemed fundamental for utterance repetition → Conduction or transcortical aphasia is a rare form of aphasia where both expression and comprehension remain intact, but the patient shows isolated impairment in the ability to repeat simple phrases (+ poor organization of articulation). IT CONFIRMS THE IDEA OF WERNICKE From Wernicke’s idea of a connection between regions governing language understanding and production, Ludwing Lichtheim (1885) hypothesized an “area of concepts” connected with both the Broca’s and Wernicke’s arears. Plus, he proposed an expanded view backed up by a novel diagram called “The Lichtheim house”. It is based on the notion that language relies on some motor aspects of production, Broca’s area, and on aspects of auditory ability to understand the meaning of messages, Wernicke’s area. By highlighting the fact that concepts are widespread in the brain and that they have to be taken into account when we create linguistic messages, Lichtheim creates other hypothetical relationships describing possible clinical groups with specific types of aphasia.
M = motor area (Broca) m = motor cortex A = comprehension (Wernicke) a = sensory cortex B = Concept area (which is distributed) If something happens in the node M, Broca aphasia occurs, while if something happens in the node A, Wernicke aphasia occurs. If there is a lesion in the connection between these two areas, precisely in the arcuate fasciculus, conduction aphasia occurs. In the case of 6, J.U. Schwarz proposed a sensory kind of aphasia different from Wernicke’s since the patient would not suffer from a destruction of the auditory word representations. This aphasia would generate a loss of understanding of both spoken and written language because there is a disconnection with the conceptual areas of the brain. Spontaneous speech would remain intact, but with paraphasias which are problems with the retrieval of concepts. Unlike Wernicke’s aphasia, spontaneous writing is intact (with paragraphias), as is repetition plus reading and writing to dictation, but the patient would not understand what he has repeated or written. Therefore, this type of aphasia affects mostly the ability to understand language in all of its form, rather than the performative aspect of repetition. → Transcortical sensory aphasia Lichtheim then hypothesized a mirror image, in the motor domain, of Schwarz’s aphasia (type 4). He reported a case of a patient that gave the impression of an absolutely deaf man, in fact, communication was only possible in writing. Following a written instruction, he could raise his arm following the sound of a bell therefore he could hear. He spoke with absolute accuracy but with a slight drawl. There were no signs of difficulty in word finding or pharaphasias. However, he could not repeat, not even in writing. → Transcortical motor aphasia
on the supramarginal and angular giry. According to this, disconnection syndromes may follow from lesions of the white matter of the hemispheres while others will involve the cortex of the angular gyrus which probably acts as a way station between the primary sensory modalities and the speech area. Geschwind had the aim of bringing a bit more informed perspective of the brain anatomy and linguistics to refine Wernicke’s idea. The two representations are quite similar, even though Wernicke’s model here is reversed. Geschwind’s schema is just more refined. This area of the brain where the arcuate fasciculus creates a bend and connects the two areas is labelled by Geschwind “a visual memory centre for words”, supporting silent reading and the auditory cortex (for silent listening). It is quite complex to turn written language into spoken language and vice versa as it requires effort from multiple brain areas. An example of how difficult is to read something aloud is dyslexia, which capitalizes on these intuitions to report what happens in the dyslexic brain. The angular gyrus is also relevant for cross-modal associations such as hear-touch or hear-look. LESION SYNDROME Motor output pathway (5) Subcortical motor aphasia Acoustic input pathway (7) Subcortical sensory aphasia Acoustic-semantic link (6) Transcortical sensory aphasia → spared repetition, paraphasias (errors in selecting words), impaired comprehension. The patient just repeats words said by the other interlocutor instead of replying to the questions (severe). The patient can also utter some words but cannot create entire sentences. Semantic-motor link 4) Transcortical motor aphasia → spared repetition, limited initiative, good comprehension. The patient knows the words but cannot reproduce them Acoustic-motor link (3) Conduction aphasia Acoustic centre (2) Sensory or Wernicke’s aphasia Motor centre (1) Motor or Broca’s aphasia Conceptual centre (B) Anomic or semantic aphasia
FLOW CHART FOR CLASSIFYING THE MAJOR APHASIA SYNDROMES:
TCA = transcortical aphasia TOMA = transcortical motor aphasia TCSA = transcortical sensory aphasia One thing to mention is that we always look at science as a Western discipline, when in reality there have been efforts across cultural domains and continents to describe language. For example, Salvatore Luria was a physician that had the chance to describe cases related to injuries in WW2 soldiers. He stated that “When a lesion of a primary speech area is observed, we may expect to see gross and complex aphasic symptoms, whereas with lesions of the marginal areas more subtle and limited impairment of speech processes is to be expected”. There are different labels for the same type of aphasia:
- Broca’s aphasia is labelled by Luria as “efferent (kinetic) motor aphasia” → breakdown of motor programming of the articulatory schema of words + disruption of syntactic schemata of sentences (telegraphic speech) + concepts are preserved here and there
- Posterior frontal damages is labelled as “dynamic aphasias” → preserved motor aspects + empty discourse + issues with pre-motor speech schemata + breakdown of inner speech.
- Wernicke’s aphasia is also known as “sensory aphasia” (post ISTG) → no phonemic hearing + no speech perception + no meaning from words (no semantics) while morphology is okay + speech is okay, but sometimes there are words salads.
- Middle/ inferior ITL becomes “Acoustic-mnestic aphasia” → disturbance of auditory memory (forgetting words, difficulties in remembering long sentences, recalling word sequences…)
- “Juncture of parietal-temporal-occipital” becomes “semantic aphasia” → difficulties in finding words and understanding logical-grammatical constructions +
However, De Bleser & Kauschke (2003) proved the ordered acquisition of nouns, verbs and their subcategories, which operates in an opposite way to language disruptions. From their study, they confirmed that children learn more nouns than verbs but when they tested this regression hypothesis into the aphasic brains, they found that it depends on the kind of patient → there was no difference between individual without aphasia and people with non- fluent Broca’s aphasia. But there were differences when the patients were especially fluent in the verbs. In conclusion, the important thing is to take into account the fact that specific aspects can play a role in how linguistic behaviour is expressed, but they are not the only thing to focus on. It was indeed the merit of Jakobson to draw aphasiology away from the mere surface of description of symptoms and to provide the first interpretations of aphasic language disturbances in a linguistically motivated way. Therefore, any kind of linguistic theory that describes a phenomenon can be used to predict behaviour in speech or language disorders. Anomic aphasia , also known as dysnomia/nominal aphasia/amnesic aphasia, is a mild, fluent type of aphasia where individuals have word retrieval failures. The connections and the conceptual network are there, but they cannot access it. When the patient sees an image, they are able to create utterances that are both complex and intact, but they cannot find the exact word to name the object (for example: image of a saw → “I have one in my garage” or “I use it to cut up wood”). Ever since the Geschwind’s revolution, neurologists have been trying to see if different aphasic conditions do share the same behaviour via the adoption of more specific and controlled tasks. Example → Sentence-picture matching task: the assistant produces a linguistic message, and the recipient must associate it with an image. Therefore, listening and processing are fundamental to answer correctly. In this experiment by Caramazza & Zurif (1976), the focus was the understanding of sentences with different grammatical features in three groups of patients with Broca’s, Wernicke’s and conduction aphasia. The participants were exposed to 4 types of sentences:
- Control sentences (simple meaning)
- Centre-embedded sentences with semantic constraints (they include a relative clause that relates to the subject of the sentence) → Non reversible.
- Reversible centre-embedded sentences (the quality in the relative clause could be attached to both actors of the sentence) → correct interpretation depends on syntactic regularities of language.
- Improbable centre-embedded sentences (conceptually implausible but grammatically correct) → well-formed but violating the speaker’s knowledge of the world. We try to trick the participants so that we see how they brain work and also what strategies they employ to correct any error. Doing something correctly can inform on the spare ability in
some linguistic domains, whereas analysing errors can illuminate what kind of deficit is there in the neurosubstrate of different conditions. In the second part of the experiment, participants have to select the sentence that matches the photo they are given. There were 4 sentence types (semantically constrained, reversible, improbable, and control) but also 4 distractor types (complement, main verb, main verb and complement, and subject-object reversal) paired with the correct on. Therefore, there is an increased degree of variability in the number of structures and errors that can be made. The results showed that Broca and conduction have a reduced capacity to algorithmically compute a full structural description of the centre-embedded reversible sentences. On the other hand, Wernicke do quite good but are insensible to the manipulation (reversibility). → Broca and conduction seem to fail more because they are impaired at the level of syntax and grammar not only in production, but also in comprehension when semantics do not support them. Whereas, Wernicke have a linear and “bad” performance since their comprehension is impaired. Moreover, Broca and conduction have reduced syntactic and grammatic skills. They understand the semantics of sentences, but they neglect the structures. They tend to do more errors in the reversal of subject and object, not assigning the correct grammatical roles. As a consequence, conduction and Broca’s aphasias seem more similar than thought, with almost overlapping patterns of error. This deficit is not in language as a whole, but rather in syntax. There is no sign of intact grammatical structures both in production and comprehension for Broca’s, while for conduction aphasics a connection to a region subserving syntactic processing might be disrupted (deficit that causes a difficulty with grammatical structures given the damage in the arcuate fasciculus). Damasio & Tranel (1993) tested the ability of three patients to understand nouns and verbs. They had to name objects, faces and verbs (actions). The patients were labelled as following: a. AN 1033 = not aphasic in the standard sense, due to damage outside the Broca’s area b. Boswell = not aphasic in the standard sense, due to damage outside the Broca’s area c. KJ 1360 = damage in the left premotor region
Dronkers and other tried to challenge Broca’s intuitions derived from his analysis of Leborgne and Lelong’s brain (autoptic superficial exam). So, they tried to bring this experiment in the XXI century by performing a fMRI scan on Leborgne’s brain. From this perspective, the damage seems to be much deeper than once thought, since Broca located the damage in the left frontal lobe. In the picture we must look at everything that is not white or grey in the brain, which can be either blood or void. From picture 2 and 3 we understand that there is a lot of dead brain tissue, so the damage extended to almost the entire left anterior part of the brain. In the case of Lelong, he suffered from a bit more posterior damage in the left prefrontal motor region. They found out a more confined damage to Broca’s area, whereas other regions surrounding the area seemed to be spared. Basically, the damage was narrower at the level of the cortex, but the damage to the fasciculus sustaining the language network in the left hemisphere was also there.
Modern approaches to aphasiology are more and more focused on how regions are connected and the damage to these networks, not only if regions are lesioned per se. These white connections are the highways through which electrical activity moves around brain regions and sustains all types of human activities. Generally speaking, we can say that there are two streams of information moving within the brain. According to the dual stream model developed by Hickok and Poeppel (2004-2007):
- the ventral stream (temporal lobes bilaterally) supports the processing of auditory-to- meaning information (old Wernicke)
- The dorsal stream processes auditory-to-articulation information and is unilaterally organized across left-hemisphere frontal speech areas and a region located at the temporal-parietal junction (Broca + additions) By putting the emphasis on the role of these two streams, we can explain the pattern of behaviour reported by early aphasiologists into a more neuroscientific ground that is not just focus on regions, but also on connections. Comprehension = input perceived by our organs are transmitted to Wernicke’s area and are then transformed into conceptual aspects Production = a concept associated with a linguistic-auditory form is passed onto the motor actualisation of it Repetition = there is no need to access concepts, because the input is just perceived and then reproduced
Level 1 = in humans the anterior segment of the arcuate fasciculus connects posterior cortex of Broca’s to anterior cortex of Geschwind’s territory. This fronto-parietal network produces and recognises informative actions. This tract is also present in the macaque brain. Level 2 = the frontal aslant tract connects Broca’s to the dorsomedial frontal cortex, forming a frontal aslant network for the processing of communicative intentions. This tract is also present in the macaque brain. Level 3 = the ventral network for lexical and semantic processing is composed of several tracts. The middle longitudinal fasciculus and inferior longitudinal fasciculus connect Wernicke’s to the anterior temporal region. Whereas the uncinate fasciculus connects the anterior temporal region to Broca’s region. Some fibres of the inferior fronto-occipital fasciculus (corresponding to extreme capsule in monkey anatomy) connect posterior temporal regions (including Wernicke’s in humans) to the frontal lobe. Level 4 = the long segment of the arcuate fasciculus connects Broca’s to Wernicke’s to support syntactic analysis and other grammatical abilities. In the monkey this posterior part of the segment is completely absent. Level 5 = the posterior segment of the arcuate fasciculus links Wernicke’s to Geschwind’s forming a temporo-parietal junction that sustains pragmatic integration. Pragmatics is indeed the highest level of communication. In the monkey brain connection between posterior temporal and angular gyrus are poorly developed. Other neurological aphasias There are types of aphasia that arise from other causes, one of them being neurological conditions. Frontotemporal Dementias (FTD) are very complex conditions where there is a disruption of both white and grey matter tracts, so that lobes shrinks and lead to atrophy. The symptoms can include linguistic deficits such as troubles in naming things, poor grammar, issues with comprehension and slower speech. It is also paired with socially inappropriateness and emotional indifference. When linguistics deficits are at the core of aphasia, these conditions fall under the label primary progressive aphasia (PPA) because they get worse over time, but the damage does not occur directly. PPA can also be found in Alzheimer’s and fronto-temporal dementias, which comprehensively impair both hemispheres. There are 3 main PPA syndromes in absence of Alzheimer’s dementia:
- Progressive nonfluent/agrammatic aphasia (PNFA) → degradation of morphology and syntax. The patients are nonfluent because the commit many phonological and articulatory mistakes, as well as numerous grammatical errors. Difficulties in understanding complex sentences and inability to repeat.
- Semantic dementia (SD) → degradation of conceptual knowledge. Grammatical and phonological aspects of language are largely spared, but semantic knowledge is slowly lost over time. Patients are usually fluent but tend to avoid basic-level words in favour
of superordinate or generic terms (animal instead of dog). Comprehension is impaired, both verbally and non-verbally.
- Logopenic progressive aphasia (LPA) → difficulties in world retrieval. Core deficits involve word retrieval and auditory-verbal short-term memory. Patients do frequent and prolonged word-finding pauses as well as intermittent self-repairs and rephrasing. Moreover, they have difficulties with complex grammatical structures (more than PNFA), paraphasias (memory) and poor repetitions. Pragmatics is a whole domain within linguistic competence. It is the study of language in its social context and assumes that words have different meanings in different contexts. The central problem for pragmatics is that sentence meaning vastly underdetermines speaker’s meaning. The goal of pragmatics is to explain how the gap between what is said and what is understood is bridged. Context, mindreading and supporting skills are fundamental. Having all language functions intact is not enough because you have to go beyond the sentence and imply meanings. Furthermore, we need to take into consideration the setting, the interlocutor, our working memory and much more. Pragmatics became relevant thanks to Paul Grice, who proposed that meaning is an intention. In 1975 he developed the cooperation principle, according to which interlocutors must contribute as it is required at the stage at which it occurs, by the accepted purpose or direction of the talk (we need to behave in a certain way when speaking). According to Grice, metaphors are a blatant violation of the first maxim of quality “do not say what you believe to be false”. On the usual assumption that the speaker is being cooperative, metaphors give rise to different implicatures. When using metaphors, we don’t say what it is objectively true, but we are comparing meanings to convince the other person of what we are saying. When the alignment is broad enough there is some mutual understanding, however what is understood depends on the interpretation of the hearer.
begins in limb or bulbar (face and neck) muscles and then spread to contiguous set of muscles, also respiratory ones. Survival ranges from months to decades, but usually less than three years from when symptoms appear. Due to the fact that muscles are slower, patients suffer with slow laborious speech, imprecise consonant production, defective articulation, marked hypernasality. However, most grammatical abilities as well as repetition are okay. Pragmatics is highly impaired because the patient cannot create cohesive discourse and grasp the meaning according to the context. In interviews, ALS patients produced fewer grammatically well-formed sentences than controls. Dysarthria only limitedly impacted on their performance. They have spared comprehension at the basic level of language, but studies show that ALS patients have reduced abilities in almost all of pragmatics skills. Real case = “il controllore ha chiuso un occhio” → The lady speaks in a nasal manner and has difficulty producing consonants (speech therapy). According to her, the inspector passed by and didn't see, so she doesn't understand the implicit meaning. She also struggles to explain the meaning of proverbs, even though she has opinions about them. There is an approximate attempt to explain the meaning from a subjective point of view, which only partially approaches the real sense. To understand if people with ALS and other cognitive impairments’ ability to grasp humour is intact phonological and mental jokes tasks (PMJ) were developed. Basically, one word in the jokes is changed with either a non-humourous or non-sequitur word to see if they grasp the change of meaning. They have to select the funny sentence and also say how much it makes them laugh, even if they pick the wrong ending. The test also studies pragmatic abilities, knowledge on vocabulary and understanding of stories. Results showed that patients with ALS scored worse than all other controls, therefore no interaction with any joke types emerged. Schizophrenia is a chronic mental illness, with global features of a progressive functional deficit (0,5-0,7% of the world’s population). The onset affects early adulthood, but changes between male (15-25 yrs) and female (25-35 yrs). It impairs both neurocognitive (memory, attention and pragmatics) and social cognition, leading to long-term disabilities. It is more related with the mind than with the body. It was firstly studied on catatonic patients during the XIX century, who were described as suffering from an early form of dementia. The term was coined later, in 1908 by Bleuler, who did not consider it dementia. He rather describe the condition as “split minds” since as the disease becomes distinct, the personality loses its unity. The primary symptoms are:
- chaotic behaviour that leads to abnormal associations
- autistic behaviour and thinking (predominance of inner life that distances the patient from external life)
- abnormal affect (difficulty in experiencing emotions in a typical way)
- ambivalence (tendency to be in the presence of contradictory feelings)
Positive symptoms (excess or distortion of normal functions) = delusions, hallucinations, illogical and disorganized thought Negative symptoms (absence of normal behaviours) = poverty of speech, apathy, social withdrawal, affective flattening In terms of speech disturbance, patients have aphasia-like impairments such as neologisms and unintelligible utterances. They may have flat intonation or unusual voice quality. Moreover, they may present deficits at the level of discourse like failure to maintain a discourse plan (tangentiality) or to interpret figurative language. They also struggle with concretism which is a failure in assigning symbolic value and making abstract connections. On the other hand, phonology, morphology and syntax are relatively intact. Moreover, deficits in working memory seem to explain difficulties in receptive grammar skills. Thought disorder also impacts on lexico-semantic abilities and pragmatics is severely impaired. When having to understand proverbs, schizophrenic patients relate concrete experiences almost encyclopaedically. Compared to ALS patients, who tried to abstract the meaning as much as possible, they are unable to infer any other meaning that goes beyond their physicality and mundane life. In another study, 67 Italian patients with chronic schizophrenia were studied particularly in their abilities at the discourse level. All of the patients had been at the time under treatment for three months at least. They were assessed for spontaneous speech, cognition, and psychopathology. 9 linguistic measures were selected from 4 domains:
- fluency → length of the utterance, pausa duration, gap duration, pause-to-word ratio
- lexical richness → type-token ratio and lexical frequency
- frequency of personal pronouns
- frequency of semantic classes → affective words and metacognitive words The researchers took into consideration both speech parameters as well as lexical-semantic- pragmatic parameters. They obtained speech samples from semi-structured interviews through dedicated software. The analysis resulted in two sets of subjects:
- high fluency, frequency of pronouns and semantic classes but low lexical richness → participants talk a lot but repeat themselves often or use words within the same semantic root.
- low fluency, frequency of pronouns and semantic classes, but high lexical richness → participants don’t talk enough, and they squeeze meaning into a very reduced number of lexical units Neither one of these samples is really effective in entertaining discourse, but they have different characteristics that involve different linguistic dimensions. Does belonging to either one of these clusters impact on other aspects of cognitive skills or quality of life? → patients in the second group also show higher scores in some psychological
