Nonverbal Stimuli Research Articles

Verbal Stimulus Control and the Intraverbal Relation.

The importance of the intraverbal relation is missed in most theories of language. Skinner (1957) attributes this to traditional semantic theories of meaning that focus on the nonverbal referents of words and neglect verbal stimuli as separate sources of control for linguistic behavior. An analysis of verbal stimulus control is presented, along with its distinction from nonverbal stimulus control and motivational control. It is suggested that there are at least four different types of increasingly complex verbal discriminations relevant to speaker and listener behavior: simple, compound, verbal conditional, and verbal function-altering (Eikeseth & Smith, 2013; Schlinger & Blakely, 1994). Separate but interlocking accounts of how these specific types of verbal stimuli produce different evocative and function-altering effects for the speaker and for the listener are provided. Finally, the effects of weakening verbal stimulus control and the loss of intraverbal behavior are considered, especially as they relate to dementia, aphasia, and traumatic brain injury.

Four Functionally Distinct Regions in the Left Supramarginal Gyrus Support Word Processing.

We used fMRI in 85 healthy participants to investigate whether different parts of the left supramarginal gyrus (SMG) are involved in processing phonological inputs and outputs. The experiment involved 2 tasks (speech production (SP) and one-back (OB) matching) on 8 different types of stimuli that systematically varied the demands on sensory processing (visual vs. auditory), sublexical phonological input (words and pseudowords vs. nonverbal stimuli), and semantic content (words and objects vs. pseudowords and meaningless baseline stimuli). In ventral SMG, we found an anterior subregion associated with articulatory sequencing (for SP > OB matching) and a posterior subregion associated with auditory short-term memory (for all auditory > visual stimuli and written words and pseudowords > objects). In dorsal SMG, a posterior subregion was most highly activated by words, indicating a role in the integration of sublexical and lexical cues. In anterior dorsal SMG, activation was higher for both pseudoword reading and object naming compared with word reading, which is more consistent with executive demands than phonological processing. The dissociation of these four “functionally-distinct” regions, all within left SMG, has implications for differentiating between different types of phonological processing, understanding the functional anatomy of language and predicting the effect of brain damage.

Delayed match-to-sample in working memory: A BrainMap meta-analysis

Working memory (WM), or the ability to temporarily store and manipulate information, is one of the most widely studied constructs in cognitive psychology. Since its inception, it has become one of the leading explanations for how humans are able to operate on a cognitive level. The current study probed the neural networks underlying one of the most commonly used tasks, delayed match-to-sample (DMTS), to study WM. An activation likelihood estimation (ALE) analysis of 42 functional neuroimaging studies (626 participants) was conducted to demonstrate neural network engagement during DMTS. Results demonstrated strong convergence in brain regions commonly associated with the working memory construct (i.e., dorsolateral prefrontal cortex, fusiform gyrus, and posterior parietal cortex). However, neural activation in two regions frequently attributed to WM were absent from this meta-analysis: the anterior cingulate and the rostral prefrontal cortex, suggesting that these regions may be more sensitive to task or stimuli characteristics. In a post-hoc analysis, we deconstructed the DMTS meta-analysis to examine nonverbal versus verbal stimuli, and found notable neurofunctional differences such that DMTS using nonverbal stimuli consistently engaged the right middle frontal gyrus (BA 6/46) and precuneus (BA 7) more so than verbal stimuli based DMTS. These results provide a foundation for future models of functional connectivity that may elucidate subtle differences in working memory attributable to pathological processes.

N-BACK TASK IN PATIENTS WITH DEMENTIA AND DEPRESSION COMPARED TO PATIENTS WITH ONLY DEPRESSION: CARDIOVASCULAR PATHOLOGY WITHOUT AND WITH DIABETES MELLITUS

The role of diabetes mellitus (DM) in cognitive decline in Alzheimer Disease (AD) remains unclear. In our previous study we did not find any additional impact of DM on the cognitive performance in demented patients with cardiovascular pathology (Bragin et al., 2013). The goal of this study is to implement the more challenging N-back task to investigate possible impact of DM in patients with dementia and depression and patients with depression alone. Data was collected from the charts of 409 patients (133 males, 276 females), mean age 76.7 ± 6.1, education 13.8 ± 2.5 yrs, all with cardiovascular pathology and with or without DM. All patients were divided into 2 groups: group 1 - patients with dementia and depression (N=318) and group 2 - patients with Depression alone (N=91). The patients in each group were further divided into subgroups of patents with No DM and DM. The cognitive battery included the MMSE, the clock drawing (CDT), the verbal fluency category (VFC) and letters (VFL) tasks, computerized simple (SRT), complex (CRT) reaction time tasks and the N-2 Back Task with non-verbal stimuli (textures) as a target. Statistical analysis was done on SPSS-21. There were no statistically significant differences in most of the cognitive tasks between No DM and DM subgroups in group 1 (dementia and depression). In group 2 (depression), the only difference between DM and No DM subgroups was on mean reaction time in N-back task. It was 1030.87± 224.87ms for no DM and 1202 ± 352.70 ms for DM (p<0.037). The N-back task reaction time is slower only in the subgroup of patients with depression and diabetes. For patients with dementia, depression and diabetes, practical application of N-back task to differential diagnostics needs further investigation.

Neuropsychological Assessment of Children with Landau-Kleffner Syndrome

Landau–Kleffner syndrome (LKS) is an epileptic encephalopathy that is marked by sudden onset of verbal auditory agnosia and subsequent deterioration in expressive language. The primary deficit is in phonological processing, possibly at the level of impaired phonological short-term memory, and it appears to create a cascade of cognitive deterioration that impacts all aspects of speech comprehension. Inability to recognize nonverbal auditory stimuli may also be present but may not emerge until later in the condition. Language recovery may occur in about one-third of patients and appears to be precipitated by resolution of the EEG abnormalities. Nonverbal intelligence is typically normal, but language skills are globally impaired. Some studies suggest deficits in visual-spatial processing and/or visual-motor integration in up to 50% of cases, but other aspects of cognitive functioning, such as memory and executive functioning, have not been well studied. Auditory working memory, however, is a consistent area of difficulty for children with LKS and appears to persist regardless of functional outcome. Behavioral disturbance is also pervasive in LKS and can sometimes be the feature requiring the most clinical attention. Recent studies have emerged that provide more thorough neurodiagnostic information about the cognitive and behavioral features of LKS, but the reported literature on expected neuropsychological findings in LKS remains sparse.

Emergence of Intraverbals with Antonyms Derived From Relations with Verbal and Nonverbal Stimuli

The present research studied the emergence of intraverbals with antonyms (e.g., “Name the opposite of empty”–“Full”) derived from learning skills with verbal and nonverbal stimuli. Five 3-year-old children learned to select the nonverbal comparison identical to a sample stimulus or of an opposite category from the sample, with a conditional discrimination procedure (e.g., selecting an empty cup in the presence of an empty cup when the contextual stimulus was “same” and selecting a full cup when the contextual stimulus was “opposite”). Then, an intraverbal probe related to these concepts was presented (e.g., “Name the opposite of empty”–“Full”). If the participant failed in the intraverbal probe, additional skills were taught or probed, and the intraverbal probe was repeated, which included conditional discriminations with more verbal stimuli than the initial conditional discrimination (e.g., selecting a full cup when told, “Point to the opposite of ‘empty’”). All 5 children demonstrated the emergence of most or all intraverbals. Two children received the sequence with a second stimulus set; they showed the emergence of intraverbals quicker than with the first stimulus set. Thus, the emergence of intraverbals after learning relations with nonverbal stimuli was demonstrated in young children. The identification of the skills present when the intraverbals emerged suggests that learning some of these skills is required for emergence, and they may be important to understand the emergence of verbal skills.

Effect of prefrontal and parietal tDCS on learning and recognition of verbal and non-verbal material.

Information learned in a spaced way is usually better recognized than information learned in a massed way. The brain mechanisms underlying this spacing effect remain unclear. We applied anodal transcranial direct current stimulation (tDCS) to the left and right prefrontal (PFC) or posterior parietal (PPC) cortices to study how stimulation influences learning and retrieval of information, as evidenced by item recognition and the spacing effect, and whether the effects are lateralized according to stimulus material and site of stimulation. We devised a continuous recognition task with verbal and non-verbal stimuli repeated either immediately or after a delay. Stimulus recognition was tested 30min later. There was a spacing effect for both materials, which, however, was not modulated by tDCS. Nonetheless, tDCS differentially impacted memory retrieval regardless of repetition mode during learning: tDCS over the PPC during learning enhanced recognition of non-verbal material regardless of side of stimulation, while tDCS over the left PFC decreased recognition regardless of material. The PPC seems to be involved specifically in the mnesic treatment of non-verbal material whereas the left PFC specifically influences learning irrespective of stimulus material. Prefrontal and posterior parietal cortices follow different lateralization rules in recognition memory.

How to Best Name a Place? Facilitation and Inhibition of Route Learning Due to Descriptive and Arbitrary Location Labels.

Establishing verbal memory traces for non-verbal stimuli was reported to facilitate or inhibit memory for the non-verbal stimuli. We show that these effects are also observed in a domain not indicated before—wayfinding. Fifty-three participants followed a guided route in a virtual environment. They were asked to remember half of the intersections by relying on the visual impression only. At the other 50% of the intersections, participants additionally heard a place name, which they were asked to memorize. For testing, participants were teleported to the intersections and were asked to indicate the subsequent direction of the learned route. In Experiment 1, intersections' names were arbitrary (i.e., not related to the visual impression). Here, participants performed more accurately at unnamed intersections. In Experiment 2, intersections' names were descriptive and participants' route memory was more accurate at named intersections. Results have implications for naming places in a city and for wayfinding aids.

Effects of Hearing Status and Sign Language Use on Working Memory

Deaf individuals have been found to score lower than hearing individuals across a variety of memory tasks involving both verbal and nonverbal stimuli, particularly those requiring retention of serial order. Deaf individuals who are native signers, meanwhile, have been found to score higher on visual-spatial memory tasks than on verbal-sequential tasks and higher on some visual-spatial tasks than hearing nonsigners. However, hearing status and preferred language modality (signed or spoken) frequently are confounded in such studies. That situation is resolved in the present study by including deaf students who use spoken language and sign language interpreting students (hearing signers) as well as deaf signers and hearing nonsigners. Three complex memory span tasks revealed overall advantages for hearing signers and nonsigners over both deaf signers and deaf nonsigners on 2 tasks involving memory for verbal stimuli (letters). There were no differences among the groups on the task involving visual-spatial stimuli. The results are consistent with and extend recent findings concerning the effects of hearing status and language on memory and are discussed in terms of language modality, hearing status, and cognitive abilities among deaf and hearing individuals.

Chapter 47 - Hypnosis as therapy for functional neurologic disorders

Suggestion in hypnosis has been applied to the treatment of functional neurologic symptoms since the earliest descriptions of hypnosis in the 19th century. Suggestion in this sense refers to an intentional communication of beliefs or ideas, whether verbally or nonverbally, to produce subjectively convincing changes in experience and behavior. The recognition of suggestion as a psychologic process with therapeutic applications was closely linked to the derivation of hypnosis from earlier healing practices. Animal magnetism, the immediate precursor of hypnosis, arrived at a psychologic concept of suggestion along with other ideas and practices which were then incorporated into hypnosis. Before then, other forms of magnetism and ritual healing practices such as exorcism involved unintentionally suggestive verbal and nonverbal stimuli. We consider the derivation of hypnosis from these practices not only to illustrate the range of suggestive processes, but also the consistency with which suggestion has been applied to the production and removal of dissociative and functional neurologic symptoms over many centuries. Nineteenth-century practitioners treated functional symptoms with induction of hypnosis per se; imperative suggestions, or commands for specific effects; "medical clairvoyance" in hypnotic trance, in which patients diagnosed their own condition and predicted the time and manner of their recovery; and suggestion without prior hypnosis, known as "fascination" or "psychotherapeutics." Modern treatments largely involve different types of imperative suggestion with or without hypnosis. However, the therapeutic application of suggestion in hypnosis to functional and other symptoms waned in the first half of the 20th century under the separate pressures of behaviorism and psychoanalysis. In recent decades suggestion in hypnosis has been more widely applied to treating functional neurologic symptoms. Suggestion is typically applied within the context of other treatment approaches, such as cognitive-behavioral, rehabilitative, or psychodynamic therapy. Suggestions are generally symptom-focused (designed to resolve a symptom) or exploratory (using methods such as revivification or age regression to explore experiences associated with symptom onset). The evidence base is dominated by case studies and series, with a paucity of randomized controlled trials. Future evaluation studies should allow for the fact that suggestion with or without hypnosis is a component of broader treatment interventions adapted to a wide range of symptoms and presentations. An important role of the concept of suggestion in the management of functional neurologic symptoms is to raise awareness of how interactions with clinicians and wider clinical contexts can alter expectancies and beliefs of patients in ways that influence the onset, course, and remission of symptoms.

Material specific lateralization of medial temporal lobe function: An fMRI investigation.

The theory of material specific lateralization of memory function posits that left and right MTL regions are asymmetrically involved in mnemonic processing of verbal and nonverbal material respectively. Lesion and functional imaging (fMRI) studies provide robust evidence for a left MTL asymmetry in the verbal memory domain. Evidence for a right MTL/nonverbal asymmetry is not as robust. A handful of fMRI studies have investigated this issue but have generally utilised nonverbal stimuli which are amenable to semantic elaboration. This fMRI study aimed to investigate the neural correlates of recognition memory processing in 20 healthy young adults (mean age = 26 years) for verbal stimuli and nonverbal stimuli that were specifically designed to minimize verbalisation. Analyses revealed that the neural correlates of recognition memory processing for verbal and nonverbal stimuli were differentiable and asymmetrically recruited the left and right MTL respectively. The right perirhinal cortex and hippocampus were preferentially involved in successful recognition memory of items devoid of semantic information. In contrast, the left anterior hippocampus was preferentially involved in successful recognition memory of stimuli which contained semantic meaning. These results suggest that the left MTL is preferentially involved in mnemonic processing of verbal/semantic information. In contrast, the right MTL is preferentially involved in visual/non-semantic mnemonic processing. We propose that during development, the left MTL becomes specialised for verbal mnemonic processing due to its proximity with left lateralised cortical language processing areas while visual/non-semantic mnemonic processing gets 'crowded out' to become predominantly, but not completely, the domain of the right MTL.

Differential processing of immediately repeated verbal and non-verbal stimuli: an evoked-potential study.

Stimuli are better retained in memory if they are repeated after a delay than if they are immediately repeated. This effect is called the spacing effect (SE). Recent electroencephalographic (EEG) studies showed that delayed repetition of meaningful designs in a continuous recognition task induces an evoked response very similar to new presentations. In contrast, immediately repeated designs induced circumscribed, stronger activation of the left medio-temporal lobe (MTL) at 200-300ms. In amnesic subjects, this signal was missing, indicating that it has a memory-protective effect. Here, high-density EEG was used in humans to explore whether meaningless verbal (non-words) and non-verbal (geometric designs) stimuli also have a SE associated with such lateralized, temporally limited activation of the left MTL upon immediate repetition. The results revealed a SE for both materials. Timing and localization of brain activity differed as a function of stimulus material. Specific responses to immediate repetitions occurred at 200-285ms for non-verbal stimuli and at 285-380ms for verbal material. Source estimations revealed increased activity in right inferior frontal areas for immediate non-verbal repetitions and in left fronto-parietal areas for immediate verbal repetition in comparison to new presentations. These findings show that, while the SE is a ubiquitous phenomenon, the neural processes underlying it vary according to stimulus material.

Lexical factors in conceptual processes: The relationship between semantic representations and their corresponding phonological and orthographic lexical forms.

To examine phonological and orthographic effects on semantic processing, the present study utilized a semantic task with nonverbal stimuli. In Experiment 1, Hebrew speakers were asked to decide whether 2 pictorial targets are semantically related or not. In Experiment 2, Hebrew speakers and non-Hebrew speakers were asked to rate the semantic relatedness of the same targets on a 5-point scale. Experiment 3 was identical to the first experiment except that the 2 pictures were presented simultaneously rather than sequentially. In all experiments, we compared responses to semantically unrelated pairs in 2 conditions: In the ambiguous condition, each pair represented 2 distinct meanings of an ambiguous Hebrew word. In the unambiguous condition, the first picture was replaced with an unambiguous control. To disentangle phonological and orthographic effects, three types of Hebrew ambiguous words were used: homonyms, homophones, and homographs. Ambiguous pairs were more difficult to be judged as semantically unrelated in comparison to their unambiguous controls. Moreover, while non-Hebrew speakers did not distinguish between the 2 lexical conditions, Hebrew speakers rated ambiguous pairs as significantly more related than their unambiguous controls. Importantly, in general, the ambiguity effect was stronger for homonyms, where both lexical forms are shared, than for either homophones or homographs, which are only phonologically or orthographically related. Thus, consistent with interactive "triangle" models, the results suggest that (a) conceptual-semantic representations automatically activate both their corresponding phonological and orthographic lexical forms, and (b) these lexical forms, once activated, may in turn affect semantic-conceptual processes via feedback connections.

Localizing Pain Matrix and Theory of Mind networks with both verbal and non-verbal stimuli

Functional localizer tasks allow researchers to identify brain regions in each individual's brain, using a combination of anatomical and functional constraints. In this study, we compare three social cognitive localizer tasks, designed to efficiently identify regions in the “Pain Matrix,” recruited in response to a person's physical pain, and the “Theory of Mind network,” recruited in response to a person's mental states (i.e. beliefs and emotions). Participants performed three tasks: first, the verbal false-belief stories task; second, a verbal task including stories describing physical pain versus emotional suffering; and third, passively viewing a non-verbal animated movie, which included segments depicting physical pain and beliefs and emotions. All three localizers were efficient in identifying replicable, stable networks in individual subjects. The consistency across tasks makes all three tasks viable localizers. Nevertheless, there were small reliable differences in the location of the regions and the pattern of activity within regions, hinting at more specific representations. The new localizers go beyond those currently available: first, they simultaneously identify two functional networks with no additional scan time, and second, the non-verbal task extends the populations in whom functional localizers can be applied. These localizers will be made publicly available.

P300 with verbal and nonverbal stimuli in normal hearing adults

AbstractThe P300 results from focusing attention on rare stimuli in the midst of other frequent stimuli; it tests recent attention and memory, both of which depend on discriminating among verbal or nonverbal stimuli. AimTo compare the P300 with verbal and nonverbal stimuli in normal-hearing adults. Material and MethodA prospective study was made of 15 male subjects aged from 22 to 55, with no hearing complaints. The subjects underwent short and long latency (P300) auditory evoked potentials with verbal and non-verbal stimuli. ResultsThe mean P300 latency with verbal stimuli was significantly higher than the P300 with nonverbal stimuli. The P300 amplitudes were significantly lower for verbal compared with nonverbal stimuli. ConclusionThere were no differences between ears with respect to P300 latencies and amplitudes for both non-verbal and verbal stimuli. Latencies were higher with verbal stimuli; amplitudes had lower values.

Long-latency auditory evoked potentials with verbal and nonverbal stimuli

IntroductionLong-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. ObjectiveTo describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. MethodsA total of 30 subjects with normal hearing were assessed, aged 18–32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000Hz – frequent and 4000Hz – rare); and verbal (/ba/ – frequent; /ga/, /da/, and /di/ – rare). ResultsConsidering the component N2 for tone burst, the lowest latency found was 217.45ms for the BA/DI stimulus; the highest latency found was 256.5ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. ConclusionThere was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude.

Potencial cortical P3: nível de dificuldade para diferentes estímulos

Objetivo Avaliar o nível de dificuldade de identificação dos estímulos verbais e não verbais, segundo classificação dos próprios participantes, e comparar com a latência do potencial cortical P3. Métodos Foram avaliados 30 sujeitos, com média de idade de 23 anos, normo-ouvintes. O potencial P3 foi pesquisado com estímulos não verbais (tone burst)e verbais (/ba/ x /di/, /ba/ x /ga/, /ba/ x /da/). Cada sujeito classificou os estímulos em "mais fácil" e "mais difícil".Resultados : A maioria dos indivíduos classificou o contraste /ba/ x /di/ como sendo o mais fácil de identificar e o contraste /ba/ x /ga/, como o mais difícil. Os sujeitos referiram que os estímulos de fala foram mais fáceis de identificar quando comparados com tone burst. O nível de dificuldade descrito pelos indivíduos influenciou nas latências dos estímulos /Di/ e /Da/, classificados como mais fáceis, e evidenciados na menor latência do P3.Conclusão O contraste /Ba/ x /Di/ foi considerado o de maior facilidade de percepção, sendo evidenciado pela menor latência do P3. Os contrastes de fala foram classificados mais fáceis quando comparados com os estímulos tonais. Essas comparações auxiliam o clínico na escolha do estímulo utilizado e no correto diagnóstico audiológico.

The image-based alcohol-action implicit association test

Background and ObjectivesPrevious work has shown that automatic alcohol-action associations, assessed by the Implicit Association Test (IAT), may play a role in hazardous drinking patterns. The majority of alcohol-related IATs have been constructed using verbal stimuli, and even those who have used pictorial stimuli have only represented beverage categories with pictures. To assess implicit appetitive responses among a broader population of alcohol users, such as those who experience limitations reading and understanding English, there may be utility in the development of an IAT that utilizes only non-verbal stimuli. MethodsThe current study presents an initial effort to develop such a task and examine its association with drinking. One hundred and fifty-three university students participated individually in a laboratory study in which they first completed a pictorial alcohol-specific approach/avoid IAT, followed by self-report measures of drinking. ResultsAs hypothesized, negative binomial regression analyses showed that IAT scores predicted the number of heavy drinking episodes and typical number of drinks per occasion. LimitationsThe use of a university student sample for this initial study represents an important limitation of this work, which should be addressed in future research. ConclusionsThese findings provide initial evidence for the potential use of non-verbal IATs to assess alcohol-related implicit cognition among adults. Implications for the assessment of hazardous drinking behavior across populations are discussed.

Why Verbalization of Non-Verbal Memory Reduces Recognition Accuracy: A Computational Approach to Verbal Overshadowing.

Verbal overshadowing refers to a phenomenon whereby verbalization of non-verbal stimuli (e.g., facial features) during the maintenance phase (after the target information is no longer available from the sensory inputs) impairs subsequent non-verbal recognition accuracy. Two primary mechanisms have been proposed for verbal overshadowing, namely the recoding interference hypothesis, and the transfer-inappropriate processing shift. The former assumes that verbalization renders non-verbal representations less accurate. In contrast, the latter assumes that verbalization shifts processing operations to a verbal mode and increases the chance of failing to return to non-verbal, face-specific processing operations (i.e., intact, yet inaccessible non-verbal representations). To date, certain psychological phenomena have been advocated as inconsistent with the recoding-interference hypothesis. These include a decline in non-verbal memory performance following verbalization of non-target faces, and occasional failures to detect a significant correlation between the accuracy of verbal descriptions and the non-verbal memory performance. Contrary to these arguments against the recoding interference hypothesis, however, the present computational model instantiated core processing principles of the recoding interference hypothesis to simulate face recognition, and nonetheless successfully reproduced these behavioral phenomena, as well as the standard verbal overshadowing. These results demonstrate the plausibility of the recoding interference hypothesis to account for verbal overshadowing, and suggest there is no need to implement separable mechanisms (e.g., operation-specific representations, different processing principles, etc.). In addition, detailed inspections of the internal processing of the model clarified how verbalization rendered internal representations less accurate and how such representations led to reduced recognition accuracy, thereby offering a computationally grounded explanation. Finally, the model also provided an explanation as to why some studies have failed to report verbal overshadowing. Thus, the present study suggests it is not constructive to discuss whether verbal overshadowing exists or not in an all-or-none manner, and instead suggests a better experimental paradigm to further explore this phenomenon.

Statistical learning as an individual ability: Theoretical perspectives and empirical evidence.

Although the power of statistical learning (SL) in explaining a wide range of linguistic functions is gaining increasing support, relatively little research has focused on this theoretical construct from the perspective of individual differences. However, to be able to reliably link individual differences in a given ability such as language learning to individual differences in SL, three critical theoretical questions should be posed: Is SL a componential or unified ability? Is it nested within other general cognitive abilities? Is it a stable capacity of an individual? Following an initial mapping sentence outlining the possible dimensions of SL, we employed a battery of SL tasks in the visual and auditory modalities, using verbal and non-verbal stimuli, with adjacent and non-adjacent contingencies. SL tasks were administered along with general cognitive tasks in a within-subject design at two time points to explore our theoretical questions. We found that SL, as measured by some tasks, is a stable and reliable capacity of an individual. Moreover, we found SL to be independent of general cognitive abilities such as intelligence or working memory. However, SL is not a unified capacity, so that individual sensitivity to conditional probabilities is not uniform across modalities and stimuli.