Surveillance MRI is associated with improved survival in patients with primary sclerosing cholangitis.

BACKGROUND: The benefits of regular surveillance imaging for cholangiocarcinoma in patients with primary sclerosing cholangitis (PSC) are unclear. Hence, we aimed to evaluate the impact of regular magnetic resonance cholangiopancreatography (MRCP) on outcomes of patients with PSC in Australia, where the practice of MRCP surveillance is variable. METHODS: The relationship between MRCP surveillance and survival outcomes was assessed in a multicenter, retrospective cohort of patients with PSC from 9 tertiary liver centers in Australia. An inverse probability of treatment weighting approach was used to balance groups across potentially confounding covariates. RESULTS: A total of 298 patients with PSC with 2117 person-years of follow-up were included. Two hundred and twenty patients (73.8%) had undergone MRCP surveillance. Regular surveillance was associated with a 71% reduced risk of death on multivariate weighted Cox analysis (HR: 0.29, 95% CI: 0.14-0.59, p < 0.001) and increased likelihood of having earlier endoscopic retrograde cholangiopancreatography from the date of PSC diagnosis in patients with a dominant stricture (p < 0.001). However, survival posthepatobiliary cancer diagnosis was not significantly different between both groups (p = 0.74). Patients who had surveillance of less than 1 scan a year (n = 41) had comparable survival (HR: 0.46, 95% CI 0.16-1.35, p = 0.16) compared to patients who had surveillance at least yearly (n = 172). CONCLUSIONS: In this multicenter cohort study that employed inverse probability of treatment weighting to minimize selection bias, regular MRCP was associated with improved overall survival in patients with PSC; however, there was no difference in survival after hepatobiliary cancer diagnosis. Further prospective studies are needed to confirm the benefits of regular MRCP and optimal imaging interval in patients with PSC.

Lenvatinib for the treatment of hepatocellular carcinoma-a real-world multicenter Australian cohort study.

INTRODUCTION: Hepatocellular carcinoma (HCC) is a serious complication of chronic liver disease. Lenvatinib is an oral multikinase inhibitor registered to treat advanced HCC. This study evaluates the real-world experience with lenvatinib in Australia. METHODS: We conducted a retrospective cohort study of patients treated with lenvatinib for advanced HCC between July 2018 and November 2020 at 11 Australian tertiary care hospitals. Baseline demographic data, tumor characteristics, lenvatinib dosing, adverse events (AEs) and clinical outcomes were collected. Overall survival (OS) was the primary outcome. Progression free survival (PFS) and AEs were secondary outcomes. RESULTS: A total of 155 patients were included and were predominantly male (90.7%) with a median age of 65 years (interquartile range [IQR]: 59-75). The main causes of chronic liver disease were hepatitis C infection (40.0%) and alcohol-related liver disease (34.2). Median OS and PFS were 7.7 (95% confidence interval [CI]: 5.8-14.0) and 5.3 months (95% CI: 2.8-9.2) respectively. Multivariate predictors of mortality were the need for dose reduction due to AEs (Hazard ratio [HR] 0.41, p < 0.01), new or worsening hypertension (HR 0.42, p < 0.01), diarrhoea (HR 0.47, p = 0.04) and more advanced BCLC stage (HR 2.50, p = 0.04). Multivariable predictors of disease progression were higher Child-Pugh score (HR 1.25, p = 0.04), the need for a dose reduction (HR 0.45, p < 0.01) and age (HR 0.96, p < 0.001). AEs occurred in 83.9% of patients with most being mild (71.6%). CONCLUSIONS: Lenvatinib remains safe and effective in real-world use. Treatment emergent diarrhoea and hypertension, and the need for dose reduction appear to predict better OS.

Irreversible electroporation versus radiofrequency ablation for hepatocellular carcinoma: a single centre propensity-matched comparison.

BACKGROUND AND AIMS: Irreversible electroporation (IRE) is a relatively new non-thermal ablative method for unresectable hepatocellular carcinoma (HCC). We aimed to compare the longer-term efficacy of IRE to the standard thermal technique of radiofrequency ablation (RFA) in HCC. METHODS: All patients who underwent IRE or RFA for HCC in our centre were identified and demographic and clinical data were analysed up until 1st March, 2020. Local recurrence-free survival (LRFS) was compared between groups after propensity score matching for age, gender, Child-Pugh grade, BCLC stage, lesion size and alpha-fetoprotein (AFP) level. RESULTS: A total of 190 HCC ablations (31 IRE and 159 RFA) were identified. After propensity score matching, we compared 25 IRE procedures (76% males, median age 62.4 years, median tumour size 20 mm) to 96 RFA procedures (84.4% males, median age 64.3 years, median tumour size 18.5 mm). LRFS did not differ between groups, with a 1-, 2- and 5-year LRFS of 80.4% (95% CI 55.8-92.2), 69.1% (95% CI 43.3-84.9) and 44.9% (95% CI 18.9-68.1%), respectively for IRE and 84.8% (95% CI 75.2-90.9), 71.3% (95% CI 58.3-81.0) and 52.1% (95% CI 35.4-66.4%), respectively for RFA (p = .63). There were no major procedure-related complications or deaths in either group. CONCLUSIONS: Whilst IRE remains a relatively novel therapy for HCC cases where standard thermal ablation is contraindicated, the LRFS in our centre is comparable to that of RFA. IRE should therefore be considered as a treatment option in such cases when available before stage-migration to non-curative therapies such as transarterial chemoembolization (TACE).

Hearing what you see: Distinct excitatory and disinhibitory mechanisms contribute to visually-evoked auditory sensations.

Visual motion or flashing lights can evoke auditory sensations in some people. This large-scale internet study aimed to validate a combined subjective/objective test of the genuineness of this putative form of synaesthesia (visually-evoked auditory response, vEAR). Correlations were measured between each individual's ratings of the vividness of auditory sensations evoked by a series of looping videos, and measurement of the videos' physical low-level motion energy, calculated using Adelson and Bergen's (1985) computational model of low-level visual motion processing. The strength of this association for each individual provided a test of how strongly subjective vEAR was driven by objective motion energy ('ME-sensitivity'). A second aim was to infer whether vEAR depends on cortical excitation and/or disinhibition of early visual and/or auditory brain areas. To achieve this, correlations were measured between the above vEAR measures and visual contrast surround-suppression, which is thought to index lateral inhibition in the early visual system. As predicted by a disinhibition account of vEAR, video ratings were overall higher in individuals showing weaker surround-suppression. Interestingly, surround-suppression and ME-sensitivity did not correlate. Additionally, both surround-suppression and ME-sensitivity each independently predicted different clusters of trait measures selected for their possible association with cortical excitability and/or disinhibition: Surround-suppression was associated with vEAR self-ratings and auditory-evoked visual phosphenes, while ME-sensitivity was independently associated with ratings of other traits including susceptibility to migraine and pattern glare. Altogether, these results suggest there are two independent mechanisms underlying vEAR and its associated traits, based putatively on cortical disinhibition versus excitability.

Wohlfahrtiimonas chitiniclastica Bloodstream Infection Due to a Maggot-infested Wound in a 54-Year-Old Male.

We report a case of Wohlfahrtiimonas chitiniclastica bacteremia and sepsis, in the setting of lower limb wounds with maggot infestation. This is the first documented infection by this organism in the Australasia/Pacific region, identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry and 16S ribosomal ribonucleic acid sequencing. Clinicians should be aware of this emerging pathogen.

Hearing through Your Eyes: Neural Basis of Audiovisual Cross-activation, Revealed by Transcranial Alternating Current Stimulation.

Some people experience auditory sensations when seeing visual flashes or movements. This prevalent synaesthesia-like visually evoked auditory response (vEAR) could result either from overexuberant cross-activation between brain areas and/or reduced inhibition of normally occurring cross-activation. We have used transcranial alternating current stimulation (tACS) to test these theories. We applied tACS at 10 Hz (alpha band frequency) or 40 Hz (gamma band), bilaterally either to temporal or occipital sites, while measuring same/different discrimination of paired auditory (A) versus visual (V) Morse code sequences. At debriefing, participants were classified as vEAR or non-vEAR, depending on whether they reported "hearing" the silent flashes. In non-vEAR participants, temporal 10-Hz tACS caused impairment of A performance, which correlated with improved V; conversely under occipital tACS, poorer V performance correlated with improved A. This reciprocal pattern suggests that sensory cortices are normally mutually inhibitory and that alpha-frequency tACS may bias the balance of competition between them. vEAR participants showed no tACS effects, consistent with reduced inhibition, or enhanced cooperation between modalities. In addition, temporal 40-Hz tACS impaired V performance, specifically in individuals who showed a performance advantage for V (relative to A). Gamma-frequency tACS may therefore modulate the ability of these individuals to benefit from recoding flashes into the auditory modality, possibly by disrupting cross-activation of auditory areas by visual stimulation. Our results support both theories, suggesting that vEAR may depend on disinhibition of normally occurring sensory cross-activation, which may be expressed more strongly in some individuals. Furthermore, endogenous alpha- and gamma-frequency oscillations may function respectively to inhibit or promote this cross-activation.

Long-term outcomes of primary sclerosing cholangitis: an Australian non-transplant tertiary hospital perspective.

BACKGROUND: There are limited Australian epidemiological and outcome data on primary sclerosing cholangitis (PSC), with the only published study involving a state liver transplantation service. AIM: The aim of this retrospective study was to evaluate the natural history, and morbidity and mortality of PSC in an Australian population managed in a large metropolitan non-transplant teaching hospital. METHODS: We identified all PSC patients managed at The Alfred Hospital over a 10-year period and analysed their clinical and demographic data. Primary outcomes were liver transplantation and death. Secondary outcomes included cholangiocarcinoma, development of cirrhosis, liver decompensation, cholangitis requiring hospital admission and the development of dominant strictures requiring dilatation. RESULTS: We identified 39 PSC patients (69% male) with a median follow-up time of 63 months (range 5-289). Median age at diagnosis was 45 years (range 10-81) and 29 (74%) patients had concurrent inflammatory bowel disease. Five patients had cirrhosis at diagnosis and 10 (26%) developed cirrhosis after a median follow up of 54 months. Three (8%) patients developed cholangiocarcinoma and one with overlap syndrome required liver transplantation. The 10- and 20-year survival rates for the entire cohort were 77.4% (95% confidence interval 55.6-89.4) and 68.8% (95% confidence interval 42.1-85) respectively. Survival in patients with small-duct disease was not different from those without. CONCLUSION: Although the PSC population in this Australian cohort appears typical of the disease, rates of liver decompensation are relatively low and the overall transplant-free survival may be better than that reported in overseas cohorts or from cohorts derived from liver transplantation centres.

Correlation of individual differences in audiovisual asynchrony across stimuli and tasks: New constraints on temporal renormalization theory.

Sight and sound are out of synch in different people by different amounts for different tasks. But surprisingly, different concurrent measures of perceptual asynchrony correlate negatively (Freeman et al., 2013). Thus, if vision subjectively leads audition in one individual, the same individual might show a visual lag in other measures of audiovisual integration (e.g., McGurk illusion, Stream-Bounce illusion). This curious negative correlation was first observed between explicit temporal order judgments and implicit phoneme identification tasks, performed concurrently as a dual task, using incongruent McGurk stimuli. Here we used a new set of explicit and implicit tasks and congruent stimuli, to test whether this negative correlation persists across testing sessions, and whether it might be an artifact of using specific incongruent stimuli. None of these manipulations eliminated the negative correlation between explicit and implicit measures. This supports the generalizability and validity of the phenomenon, and offers new theoretical insights into its explanation. Our previously proposed "temporal renormalization" theory assumes that the timings of sensory events registered within the brain's different multimodal subnetworks are each perceived relative to a representation of the typical average timing of such events across the wider network. Our new data suggest that this representation is stable and generic, rather than dependent on specific stimuli or task contexts, and that it may be acquired through experience with a variety of simultaneous stimuli. Our results also add further evidence that speech comprehension may be improved in some individuals by artificially delaying voices relative to lip-movements. (PsycINFO Database Record

Sounds from seeing silent motion: Who hears them, and what looks loudest?

Some people hear what they see: car indicator lights, flashing neon shop signs, and people's movements as they walk may all trigger an auditory sensation, which we call the visual-evoked auditory response (vEAR or 'visual ear'). We have conducted the first large-scale online survey (N > 4000) of this little-known phenomenon. We analysed the prevalence of vEAR, what induces it, and what other traits are associated with it. We assessed prevalence by asking whether respondents had previously experienced vEAR. Participants then rated silent videos for vividness of evoked auditory sensations, and answered additional trait questions. Prevalence appeared higher relative to other typical synaesthesias. Prior awareness and video ratings were associated with greater frequency of other synaesthesias, including flashes evoked by sounds, and musical imagery. Higher-rated videos often depicted meaningful events that predicted sounds (e.g., collisions). However, even videos containing abstract flickering or moving patterns could also elicit higher ratings, despite having no predictable association with sounds. Such videos had higher levels of raw 'motion energy' (ME), which we quantified using a simple computational model of motion processing in early visual cortex. Critically, only respondents reporting prior awareness of vEAR tended to show a positive correlation between video ratings and ME. This specific sensitivity to ME suggests that in vEAR, signals from visual motion processing may affect audition relatively directly without requiring higher-level interpretative processes. Our other findings challenge the popular assumption that individuals with synaesthesia are rare and have ideosyncratic patterns of brain hyper-connectivity. Instead, our findings of apparently high prevalence and broad associations with other synaesthesias and traits are jointly consistent with a common dependence on normal variations in physiological mechanisms of disinhibition or excitability of sensory brain areas and their functional connectivity. The prevalence of vEAR makes it easier to test such hypotheses further, and makes the results more relevant to understanding not only synaesthetic anomalies but also normal perception.

Sight and sound persistently out of synch: stable individual differences in audiovisual synchronisation revealed by implicit measures of lip-voice integration.

Are sight and sound out of synch? Signs that they are have been dismissed for over two centuries as an artefact of attentional and response bias, to which traditional subjective methods are prone. To avoid such biases, we measured performance on objective tasks that depend implicitly on achieving good lip-synch. We measured the McGurk effect (in which incongruent lip-voice pairs evoke illusory phonemes), and also identification of degraded speech, while manipulating audiovisual asynchrony. Peak performance was found at an average auditory lag of ~100 ms, but this varied widely between individuals. Participants' individual optimal asynchronies showed trait-like stability when the same task was re-tested one week later, but measures based on different tasks did not correlate. This discounts the possible influence of common biasing factors, suggesting instead that our different tasks probe different brain networks, each subject to their own intrinsic auditory and visual processing latencies. Our findings call for renewed interest in the biological causes and cognitive consequences of individual sensory asynchronies, leading potentially to fresh insights into the neural representation of sensory timing. A concrete implication is that speech comprehension might be enhanced, by first measuring each individual's optimal asynchrony and then applying a compensatory auditory delay.

A deafening flash! Visual interference of auditory signal detection.

In some people, visual stimulation evokes auditory sensations. How prevalent and how perceptually real is this? 22% of our neurotypical adult participants responded 'Yes' when asked whether they heard faint sounds accompanying flash stimuli, and showed significantly better ability to discriminate visual 'Morse-code' sequences. This benefit might arise from an ability to recode visual signals as sounds, thus taking advantage of superior temporal acuity of audition. In support of this, those who showed better visual relative to auditory sequence discrimination also had poorer auditory detection in the presence of uninformative visual flashes, though this was independent of awareness of visually-evoked sounds. Thus a visually-evoked auditory representation may occur subliminally and disrupt detection of real auditory signals. The frequent natural correlation between visual and auditory stimuli might explain the surprising prevalence of this phenomenon. Overall, our results suggest that learned correspondences between strongly correlated modalities may provide a precursor for some synaesthetic abilities.

fMRI correlates of object-based attentional facilitation vs. suppression of irrelevant stimuli, dependent on global grouping and endogenous cueing.

Theories of object-based attention often make two assumptions: that attentional resources are facilitatory, and that they spread automatically within grouped objects. Consistent with this, ignored visual stimuli can be easier to process, or more distracting, when perceptually grouped with an attended target stimulus. But in past studies, the ignored stimuli often shared potentially relevant features or locations with the target. In this fMRI study, we measured the effects of attention and grouping on Blood Oxygenation Level Dependent (BOLD) responses in the human brain to entirely task-irrelevant events. Two checkerboards were displayed each in opposite hemifields, while participants responded to check-size changes in one pre-cued hemifield, which varied between blocks. Grouping (or segmentation) between hemifields was manipulated between blocks, using common (vs. distinct) motion cues. Task-irrelevant transient events were introduced by randomly changing the color of either checkerboard, attended or ignored, at unpredictable intervals. The above assumptions predict heightened BOLD signals for irrelevant events in attended vs. ignored hemifields for ungrouped contexts, but less such attentional modulation under grouping, due to automatic spreading of facilitation across hemifields. We found the opposite pattern, in primary visual cortex. For ungrouped stimuli, BOLD signals associated with task-irrelevant changes were lower, not higher, in the attended vs. ignored hemifield; furthermore, attentional modulation was not reduced but actually inverted under grouping, with higher signals for events in the attended vs. ignored hemifield. These results challenge two popular assumptions underlying object-based attention. We consider a broader biased-competition framework: task-irrelevant stimuli are suppressed according to how strongly they compete with task-relevant stimuli, with intensified competition when the irrelevant features or locations comprise the same object.

Commonalities for numerical and continuous quantity skills at temporo-parietal junction.

How do our abilities to process number and other continuous quantities such as time and space relate to each other? Recent evidence suggests that these abilities share common magnitude processing and neural resources, although other findings also highlight the role of dimension-specific processes. To further characterize the relation between number, time, and space, we first examined them in a population with a developmental numerical dysfunction (developmental dyscalculia) and then assessed the extent to which these abilities correlated both behaviorally and anatomically in numerically normal participants. We found that (1) participants with dyscalculia showed preserved continuous quantity processing and (2) in numerically normal adults, numerical and continuous quantity abilities were at least partially dissociated both behaviorally and anatomically. Specifically, gray matter volume correlated with both measures of numerical and continuous quantity processing in the right TPJ; in contrast, individual differences in number proficiency were associated with gray matter volume in number-specific cortical regions in the right parietal lobe. Together, our new converging evidence of selective numerical impairment and of number-specific brain areas at least partially distinct from common magnitude areas suggests that the human brain is equipped with different ways of quantifying the outside world.

Sight and sound out of synch: fragmentation and renormalisation of audiovisual integration and subjective timing.

The sight and sound of a person speaking or a ball bouncing may seem simultaneous, but their corresponding neural signals are spread out over time as they arrive at different multisensory brain sites. How subjective timing relates to such neural timing remains a fundamental neuroscientific and philosophical puzzle. A dominant assumption is that temporal coherence is achieved by sensory resynchronisation or recalibration across asynchronous brain events. This assumption is easily confirmed by estimating subjective audiovisual timing for groups of subjects, which is on average similar across different measures and stimuli, and approximately veridical. But few studies have examined normal and pathological individual differences in such measures. Case PH, with lesions in pons and basal ganglia, hears people speak before seeing their lips move. Temporal order judgements (TOJs) confirmed this: voices had to lag lip-movements (by ∼200 msec) to seem synchronous to PH. Curiously, voices had to lead lips (also by ∼200 msec) to maximise the McGurk illusion (a measure of audiovisual speech integration). On average across these measures, PH's timing was therefore still veridical. Age-matched control participants showed similar discrepancies. Indeed, normal individual differences in TOJ and McGurk timing correlated negatively: subjects needing an auditory lag for subjective simultaneity needed an auditory lead for maximal McGurk, and vice versa. This generalised to the Stream-Bounce illusion. Such surprising antagonism seems opposed to good sensory resynchronisation, yet average timing across tasks was still near-veridical. Our findings reveal remarkable disunity of audiovisual timing within and between subjects. To explain this we propose that the timing of audiovisual signals within different brain mechanisms is perceived relative to the average timing across mechanisms. Such renormalisation fully explains the curious antagonistic relationship between disparate timing estimates in PH and healthy participants, and how they can still perceive the timing of external events correctly, on average.

fMRI correlates of subjective reversals in ambiguous structure-from-motion.

We used fMRI to examine the neural correlates of subjective reversals for bistable structure-from-motion. We compared transparent random-dot kinematograms depicting either a cylinder rotating in depth or two flat surfaces translating in opposite directions at apparently different depths. For both such stimuli, the motion of dots on the different apparent depth planes typically appears to reverse direction periodically on prolonged viewing. Yet for cylindrical but not flat stimuli, such subjective reversals also coincide with apparent reversal of 3D rotation direction. We hypothesized that the lateral occipital complex (region LOC), sensitive to 3D form, might show greater event-related activity for subjective reversals of cylindrical than flat stimuli; conversely, motion-sensitive hMT+/V5 should respond in common to subjective reversals for either type of stimuli, as both are perceived as changes in planar motion. We obtained an event-related measure of neural activity associated with subjective reversals after first factoring out block-related differences between cylindrical versus flat stimuli (and thereby the associated low-level blocked stimulus differences). In support of our hypothesis, only the cylindrical stimuli produced reversal-related activity in contralateral human LOC. In contrast, the hMT+/V5 complex was activated alike by subjective reversals for both cylindrical and flat stimuli. Intriguingly, V1 also showed (contralateral) specificity for rotational reversals, suggesting a possible feedback influence from LOC. These results reveal specific neural correlates for subjective switches of 3D rotation versus translation, as distinct from subjective reversals in general.

Does visual flicker phase at gamma frequency modulate neural signal propagation and stimulus selection?

Oscillatory synchronization of neuronal populations has been proposed to play a role in perceptual integration and attentional processing. However, some conflicting evidence has been found with respect to its causal relevance for sensory processing, particularly when using flickering visual stimuli with the aim of driving oscillations. We tested psychophysically whether the relative phase of gamma frequency flicker (60 Hz) between stimuli modulates well-known facilitatory lateral interactions between collinear Gabor patches (Experiment 1) or crowding of a peripheral target by irrelevant distractors (Experiment 2). Experiment 1 assessed the impact of suprathreshold Gabor flankers on detection of a near-threshold central Gabor target ("Lateral interactions paradigm"). The flanking stimuli could flicker either in phase or in anti-phase with each other. The typical facilitation of target detection was found with collinear flankers, but this was unaffected by flicker phase. Experiment 2 employed a "crowding" paradigm, where orientation discrimination of a peripheral target Gabor patch is disrupted when surrounded by irrelevant distractors. We found the usual crowding effect, which declined with spatial separation, but this was unaffected by relative flicker phase between target and distractors at all separations. These results imply that externally driven manipulations of gamma frequency phase cannot modulate perceptual integration in vision.

Time processing in dyscalculia.

To test whether atypical number development may affect other types of quantity processing, we investigated temporal discrimination in adults with developmental dyscalculia (DD). This also allowed us to test whether number and time may be sub-served by a common quantity system or decision mechanisms: if they do, both should be impaired in dyscalculia, but if number and time are distinct they should dissociate. Participants judged which of two successively presented horizontal lines was longer in duration, the first line being preceded by either a small or a large number prime ("1" or "9") or by a neutral symbol ("#"), or in a third task participants decided which of two Arabic numbers (either "1," "5," "9") lasted longer. Results showed that (i) DD's temporal discriminability was normal as long as numbers were not part of the experimental design, even as task-irrelevant stimuli; however (ii) task-irrelevant numbers dramatically disrupted DD's temporal discriminability the more their salience increased, though the actual magnitude of the numbers had no effect; in contrast (iii) controls' time perception was robust to the presence of numbers but modulated by numerical quantity: therefore small number primes or numerical stimuli seemed to make durations appear shorter than veridical, but longer for larger numerical prime or numerical stimuli. This study is the first to show spared temporal discrimination - a dimension of continuous quantity - in a population with a congenital number impairment. Our data reinforce the idea of a partially shared quantity system across numerical and temporal dimensions, which supports both dissociations and interactions among dimensions; however, they suggest that impaired number in DD is unlikely to originate from systems initially dedicated to continuous quantity processing like time.

Numbers and time doubly dissociate.

The magnitude dimensions of number, time and space have been suggested to share some common magnitude processing, which may imply symmetric interaction among dimensions. Here we challenge these suggestions by presenting a double dissociation between two neuropsychological patients with left (JT) and right (CB) parietal lesions and selective impairment of number and time processing respectively. Both patients showed an influence of task-irrelevant number stimuli on time but not space processing. In JT otherwise preserved time processing was severely impaired in the mere presence of task-irrelevant numbers, which themselves could not be processed accurately. In CB, impaired temporal estimation was influenced by preserved number processing: small numbers made (already grossly underestimated) time intervals appear even shorter relative to large numbers. However, numerical estimation was not influenced by time in healthy controls and in both patients. This new double dissociation between number and time processing and the asymmetric interaction of number on time: (1) provides further support to the hypothesis of a partly shared magnitude system among dimensions, instead of the proposal of a single, fully shared system or of independent magnitude systems which would not explain dissociations or interactions among dimensions; (2) may be explained in terms of a stable hierarchy of dimensions, with numbers being the strongest.