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1.
Conscious Cogn ; 121: 103694, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38657474

RESUMEN

Mental rotation tasks are frequently used as standard measures of mental imagery. However, aphantasia research has brought such use into question. Here, we assessed a large group of individuals who lack visual imagery (aphantasia) on two mental rotation tasks: a three-dimensional block-shape, and a human manikin rotation task. In both tasks, those with aphantasia had slower, but more accurate responses than controls. Both groups demonstrated classic linear increases in response time and error-rate as functions of angular disparity. In the three-dimensional block-shape rotation task, a within-group speed-accuracy trade-off was found in controls, whereas faster individuals in the aphantasia group were also more accurate. Control participants generally favoured using object-based mental rotation strategies, whereas those with aphantasia favoured analytic strategies. These results suggest that visual imagery is not crucial for successful performance in classical mental rotation tasks, as alternative strategies can be effectively utilised in the absence of holistic mental representations.


Asunto(s)
Imaginación , Humanos , Imaginación/fisiología , Masculino , Adulto , Femenino , Desempeño Psicomotor/fisiología , Adulto Joven , Percepción Espacial/fisiología , Rotación , Persona de Mediana Edad , Reconocimiento Visual de Modelos/fisiología , Tiempo de Reacción/fisiología
2.
Neurosci Res ; 201: 27-30, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38311033

RESUMEN

The inability to visualise was given the name aphantasia in 2015 by Zeman and colleagues. In 2018 we published research showing that fifteen individuals who self-identified as having aphantasia also demonstrated a lack of sensory visual imagery when undergoing the binocular rivalry imagery paradigm, suggesting more than just a metacognitive difference. Here we update these findings with over fifty participants with aphantasia and show that there is evidence for a lack of sensory imagery in aphantasia. How the binocular rivalry paradigm scores relate to the vividness of visual imagery questionnaire (VVIQ) and how aphantasia can be confirmed is discussed.


Asunto(s)
Imágenes en Psicoterapia , Imaginación , Humanos , Encuestas y Cuestionarios , Percepción Visual
4.
Neurosci Res ; 201: 50-59, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38029861

RESUMEN

Cognitive neuroscience research on mental imagery has largely focused on the visual imagery modality in unimodal task contexts. Recent studies have uncovered striking individual differences in visual imagery capacity, with some individuals reporting a subjective absence of conscious visual imagery ability altogether ("aphantasia"). However, naturalistic mental imagery is often multi-sensory, and preliminary findings suggest that many individuals with aphantasia also report a subjective lack of mental imagery in other sensory domains (such as auditory or olfactory imagery). In this paper, we perform a series of cluster analyses on the multi-sensory imagery questionnaire scores of two large groups of aphantasic subjects, defining latent sub-groups in this sample population. We demonstrate that aphantasia is a heterogenous phenomenon characterised by dominant sub-groups of individuals with visual aphantasia (those who report selective visual imagery absence) and multi-sensory aphantasia (those who report an inability to generate conscious mental imagery in any sensory modality). We replicate our findings in a second large sample and show that more unique aphantasia sub-types also exist, such as individuals with selectively preserved mental imagery in only one sensory modality (e.g. intact auditory imagery). We outline the implications of our findings for network theories of mental imagery, discussing how unique aphantasia aetiologies with distinct self-report patterns might reveal alterations to various levels of the sensory processing hierarchy implicated in mental imagery.


Asunto(s)
Imaginación , Percepción Visual , Humanos , Imágenes en Psicoterapia
5.
Psychol Sci ; 34(11): 1229-1243, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37782827

RESUMEN

Recent research suggests imagery is functionally equivalent to a weak form of visual perception. Here we report evidence across five independent experiments on adults that perception and imagery are supported by fundamentally different mechanisms: Whereas perceptual representations are largely formed via increases in excitatory activity, imagery representations are largely supported by modulating nonimagined content. We developed two behavioral techniques that allowed us to first put the visual system into a state of adaptation and then probe the additivity of perception and imagery. If imagery drives similar excitatory visual activity to perception, pairing imagery with perceptual adapters should increase the state of adaptation. Whereas pairing weak perception with adapters increased measures of adaptation, pairing imagery reversed their effects. Further experiments demonstrated that these nonadditive effects were due to imagery weakening representations of nonimagined content. Together these data provide empirical evidence that the brain uses categorically different mechanisms to represent imagery and perception.


Asunto(s)
Imaginación , Percepción Visual , Adulto , Humanos , Visión Ocular , Encéfalo
6.
Cell Rep ; 42(8): 112925, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37552601

RESUMEN

The neddylation inhibitor MLN4924/Pevonedistat is in clinical trials for multiple cancers. Efficacy is generally attributed to cullin RING ligase (CRL) inhibition, but the contribution of non-CRL targets is unknown. Here, CRISPR screens map MLN4924-monotherapy sensitivity in retinoblastoma to a classic DNA damage-induced p53/E2F3/BAX-dependent death effector network, which synergizes with Nutlin3a or Navitoclax. In monotherapy-resistant cells, MLN4924 plus standard-of-care topotecan overcomes resistance, but reduces DNA damage, instead harnessing ribosomal protein nucleolar-expulsion to engage an RPL11/p21/MYCN/E2F3/p53/BAX synergy network that exhibits extensive cross-regulation. Strikingly, unneddylatable RPL11 substitutes for MLN4924 to perturb nucleolar function and enhance topotecan efficacy. Orthotopic tumors exhibit complete responses while preserving visual function. Moreover, MLN4924 plus melphalan deploy this DNA damage-independent strategy to synergistically kill multiple myeloma cells. Thus, MLN4924 synergizes with standard-of-care drugs to unlock a nucleolar death effector network across cancer types implying broad therapeutic relevance.


Asunto(s)
Topotecan , Proteína p53 Supresora de Tumor , Proteína X Asociada a bcl-2 , Línea Celular Tumoral , Ciclopentanos/farmacología , Proteínas Ribosómicas , Apoptosis , Proteína NEDD8
7.
PLoS One ; 18(7): e0289313, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37506067

RESUMEN

Subliminal information can influence our conscious life. Subliminal stimuli can influence cognitive tasks, while endogenous subliminal neural information can sway decisions before volition. Are decisions inextricably biased towards subliminal information? Or can they diverge away from subliminal biases via training? We report that implicit bias training can remove biases from subliminal sensory primes. We first show that subliminal stimuli biased an imagery-content decision task. Participants (n = 17) had to choose one of two different patterns to subsequently imagine. Subliminal primes significantly biased decisions towards imagining the primed option. Then, we trained participants (n = 7) to choose the non-primed option, via post choice feedback. This training was successful despite participants being unaware of the purpose or structure of the reward schedule. This implicit bias training persisted up to one week later. Our proof-of-concept study indicates that decisions might not always have to be biased towards non-conscious information, but instead can diverge from subliminal primes through training.


Asunto(s)
Sesgo Implícito , Estimulación Subliminal , Humanos , Volición , Sesgo
8.
Sci Rep ; 12(1): 14438, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-36002557

RESUMEN

The lack of therapeutic options to fight Covid-19 has contributed to the current global pandemic. Despite the emergence of effective vaccines, development of broad-spectrum antiviral treatment remains a significant challenge, in which antimicrobial photodynamic therapy (aPDT) may play a role, especially at early stages of infection. aPDT of the nares with methylene blue (MB) and non-thermal light has been successfully utilized to inactivate both bacterial and viral pathogens in the perioperative setting. Here, we investigated the effect of MB-aPDT to inactivate human betacoronavirus OC43 and SARS-CoV-2 in vitro and in a proof-of-principle COVID-19 clinical trial to test, in a variety of settings, the practicality, technical feasibility, and short-term efficacy of the method. aPDT yielded inactivation of up to 6-Logs in vitro, as measured by RT-qPCR and infectivity assay. From a photo-physics perspective, the in vitro results suggest that the response is not dependent on the virus itself, motivating potential use of aPDT for local destruction of SARS-CoV-2 and its variants. In the clinical trial we observed variable effects on viral RNA in nasal-swab samples as assessed by RT-qPCR attributed to aPDT-induced RNA fragmentation causing falsely-elevated counts. However, the viral infectivity in clinical nares swabs was reduced in 90% of samples and undetectable in 70% of samples. This is the first demonstration based on quantitative clinical viral infectivity measurements that MB-aPDT is a safe, easily delivered and effective front-line technique that can reduce local SARS-CoV-2 viral load.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Desinfección , Nariz , Fotoquimioterapia , Antiinfecciosos/efectos adversos , Antiinfecciosos/farmacología , Desinfección/métodos , Estudios de Factibilidad , Humanos , Azul de Metileno/efectos adversos , Azul de Metileno/farmacología , Nariz/virología , Pandemias , ARN Viral/análisis , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Resultado del Tratamiento , Carga Viral/efectos de los fármacos
9.
Cognition ; 227: 105192, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35752014

RESUMEN

Our capacity to re-experience the past and simulate the future is thought to depend heavily on visual imagery, which allows us to construct complex sensory representations in the absence of sensory stimulation. There are large individual differences in visual imagery ability, but their impact on autobiographical memory and future prospection remains poorly understood. Research in this field assumes the normative use of visual imagery as a cognitive tool to simulate the past and future, however some individuals lack the ability to visualise altogether (a condition termed "aphantasia"). Aphantasia represents a rare and naturally occurring knock-out model for examining the role of visual imagery in episodic memory recall. Here, we assessed individuals with aphantasia on an adapted form of the Autobiographical Interview, a behavioural measure of the specificity and richness of episodic details underpinning the memory of events. Aphantasic participants generated significantly fewer episodic details than controls for both past and future events. This effect was most pronounced for novel future events, driven by selective reductions in visual detail retrieval, accompanied by comparatively reduced ratings of the phenomenological richness of simulated events, and paralleled by quantitative linguistic markers of reduced perceptual language use in aphantasic participants compared to those with visual imagery. Our findings represent the first systematic evidence (using combined objective and subjective data streams) that aphantasia is associated with a diminished ability to re-experience the past and simulate the future, indicating that visual imagery is an important cognitive tool for the dynamic retrieval and recombination of episodic details during mental simulation.


Asunto(s)
Imaginación , Memoria Episódica , Predicción , Humanos , Imaginación/fisiología , Individualidad , Recuerdo Mental/fisiología
10.
PLoS One ; 17(5): e0268340, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35544541

RESUMEN

Continued waves, new variants, and limited vaccine deployment mean that SARS-CoV-2 tests remain vital to constrain the coronavirus disease 2019 (COVID-19) pandemic. Affordable, point-of-care (PoC) tests allow rapid screening in non-medical settings. Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) is an appealing approach. A crucial step is to optimize testing in low/medium resource settings. Here, we optimized RT-LAMP for SARS-CoV-2 and human ß-actin, and tested clinical samples in multiple countries. "TTTT" linker primers did not improve performance, and while guanidine hydrochloride, betaine and/or Igepal-CA-630 enhanced detection of synthetic RNA, only the latter two improved direct assays on nasopharygeal samples. With extracted clinical RNA, a 20 min RT-LAMP assay was essentially as sensitive as RT-PCR. With raw Canadian nasopharygeal samples, sensitivity was 100% (95% CI: 67.6% - 100%) for those with RT-qPCR Ct values ≤ 25, and 80% (95% CI: 58.4% - 91.9%) for those with 25 < Ct ≤ 27.2. Highly infectious, high titer cases were also detected in Colombian and Ecuadorian labs. We further demonstrate the utility of replacing thermocyclers with a portable PoC device (FluoroPLUM). These combined PoC molecular and hardware tools may help to limit community transmission of SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Canadá , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Sistemas de Atención de Punto , ARN Viral/análisis , ARN Viral/genética , SARS-CoV-2/genética , Sensibilidad y Especificidad
12.
Commun Biol ; 5(1): 411, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35505181

RESUMEN

The Tg(Pax6-cre,GFP)2Pgr (α-Cre) mouse is a commonly used Cre line thought to be retinal-specific. Using targeted locus amplification (TLA), we mapped the insertion site of the transgene, and defined primers useful to deduce zygosity. Further analyses revealed four tandem copies of the transgene. The insertion site mapped to clusters of vomeronasal and olfactory receptor genes. Using R26R and Ai14 Cre reporter mice, we confirmed retinal Cre activity, but also detected expression in Gα0+ olfactory neurons. Most α-Cre+ olfactory neurons do not express Pax6, implicating the influence of neighboring regulatory elements. RT-PCR and buried food pellet test did not detect any effects of the transgene on flanking genes in the nasal mucosa and retina. Together, these data precisely map α-Cre, show that it does not affect surrounding loci, but reveal previously unanticipated transgene expression in olfactory neurons. The α-Cre mouse can be a valuable tool in both retinal and olfactory research.


Asunto(s)
Neuronas , Retina , Animales , Integrasas , Ratones , Ratones Transgénicos , Transgenes
13.
Cortex ; 150: 149-152, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35314076

RESUMEN

Recently, the term 'aphantasia' has become current in scientific and public discourse to denote the absence of mental imagery. However, new terms for aphantasia or its subgroups have recently been proposed, e.g., 'dysikonesia' or 'anauralia', which complicates the literature, research communication and understanding for the general public. Before further terms emerge, we advocate the consistent use of the term 'aphantasia' as it can be used flexibly and precisely, and is already widely known in the scientific community and among the general public.


Asunto(s)
Imaginación , Percepción Visual , Humanos , Imágenes en Psicoterapia
14.
Elife ; 112022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35356890

RESUMEN

The pupillary light response is an important automatic physiological response which optimizes light reaching the retina. Recent work has shown that the pupil also adjusts in response to illusory brightness and a range of cognitive functions, however, it remains unclear what exactly drives these endogenous changes. Here, we show that the imagery pupillary light response correlates with objective measures of sensory imagery strength. Further, the trial-by-trial phenomenological vividness of visual imagery is tracked by the imagery pupillary light response. We also demonstrated that a group of individuals without visual imagery (aphantasia) do not show any significant evidence of an imagery pupillary light response, however they do show perceptual pupil light responses and pupil dilation with larger cognitive load. Our results provide evidence that the pupillary light response indexes the sensory strength of visual imagery. This work also provides the first physiological validation of aphantasia.


Asunto(s)
Imaginación , Pupila , Cognición/fisiología , Humanos , Imágenes en Psicoterapia , Imaginación/fisiología , Percepción Visual/fisiología
15.
Cell Rep ; 38(9): 110448, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35235778

RESUMEN

Progression through G1/S phase of the cell cycle is coordinated by cyclin-dependent kinase (CDK) activities. Here, we find that the requirement for different CDK activities and cyclins in driving cancer cell cycles is highly heterogeneous. The differential gene requirements associate with tumor origin and genetic alterations. We define multiple mechanisms for G1/S progression in RB-proficient models, which are CDK4/6 independent and elicit resistance to FDA-approved inhibitors. Conversely, RB-deficient models are intrinsically CDK4/6 independent, but exhibit differential requirements for cyclin E. These dependencies for CDK and cyclins associate with gene expression programs that denote intrinsically different cell-cycle states. Mining therapeutic sensitivities shows that there are reciprocal vulnerabilities associated with RB1 or CCND1 expression versus CCNE1 or CDKN2A. Together, these findings illustrate the complex nature of cancer cell cycles and the relevance for precision therapeutic intervention.


Asunto(s)
Quinasas Ciclina-Dependientes , Neoplasias , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , División Celular , Quinasa 4 Dependiente de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Quinasas Ciclina-Dependientes/metabolismo , Humanos , Neoplasias/genética
16.
Clin Cancer Res ; 28(9): 1966-1978, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35165102

RESUMEN

PURPOSE: Small cell lung cancer (SCLC) is an aggressive disease with an overall 5-year survival rate of less than 10%. Treatment for SCLC with cisplatin/etoposide chemotherapy (C/E) ± radiotherapy has changed modestly over several decades. The ubiquitin-proteasome system is an underexplored therapeutic target for SCLC. We preclinically evaluated TAK-243, a first-in-class small molecule E1 inhibitor against UBA1. EXPERIMENTAL DESIGN: We assessed TAK-243 in 26 SCLC cell-lines as monotherapy and combined with C/E, the PARP-inhibitor, olaparib, and with radiation using cell viability assays. We interrogated TAK-243 response with gene expression to identify candidate biomarkers. We evaluated TAK-243 alone and in combination with olaparib or radiotherapy with SCLC patient-derived xenografts (PDX). RESULTS: Most SCLC cell lines were sensitive to TAK-243 monotherapy (EC50 median 15.8 nmol/L; range 10.2 nmol/L-367.3 nmol/L). TAK-243 sensitivity was associated with gene-sets involving the cell cycle, DNA and chromatin organization, and DNA damage repair, while resistance associated with cellular respiration, translation, and neurodevelopment. These associations were also observed in SCLC PDXs. TAK-243 synergized with C/E and olaparib in vitro across sensitive and resistant SCLC cell lines. Considerable TAK-243-olaparib synergy was observed in an SCLC PDX resistant to both drugs individually. TAK-243 radiosensitization was also observed in an SCLC PDX. CONCLUSIONS: TAK-243 displays efficacy in SCLC preclinical models. Enrichment of gene sets is associated with TAK-243 sensitivity and resistance. TAK-243 exhibits synergy when combined with genotoxic therapies in cell lines and PDXs. TAK-243 is a potential therapeutic strategy to improve SCLC patient outcomes, both as a single agent and in combination with existing therapies.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Complejo de la Endopetidasa Proteasomal , Pirazoles , Pirimidinas , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/genética , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Sulfuros , Sulfonamidas , Ubiquitina , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Mol Cell Oncol ; 8(5): 1981111, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34859143

RESUMEN

The inherent complexity of cancer complicates treatment. Identifying higher-order principles that govern cancer biology can circumvent this problem and pinpoint broadly applicable treatment options. We recently found that opposite expression and pro- versus anti-cancer activity of a single transcriptional complex functionally stratifies cancer into binary superclasses.

18.
STAR Protoc ; 2(4): 100870, 2021 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-34632420

RESUMEN

Ectopic/overexpression systems are important for studying protein function, but care must be taken to avoid artifacts due to excessively high levels of overexpression. To study the function of YAP/TAZ in YAP/TAZ-deficient (YAPoff) cancers, we developed a lentiviral system using weak, constitutive promoters to ectopically express YAP/TAZ to physiologically relevant levels. We detail this system along with protocols to assess YAP/TAZ expression by flow cytometry and quantitative western blotting. This system can also be easily adapted for the study of other proteins. For complete details on the use and execution of this protocol, please refer to Pearson et al. (2021).


Asunto(s)
Aciltransferasas/genética , Lentivirus/genética , Neoplasias/metabolismo , Proteínas Recombinantes/genética , Proteínas Señalizadoras YAP/genética , Aciltransferasas/metabolismo , Animales , Western Blotting , Línea Celular Tumoral , Humanos , Ratones , Proteínas Recombinantes/metabolismo , Proteínas Señalizadoras YAP/metabolismo
19.
Cortex ; 143: 237-253, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34482017

RESUMEN

Visual working memory paradigms involve retaining and manipulating visual information in mind over a period of seconds. Evidence suggests that visual imagery (sensory recruitment) is a strategy used by many to retain visual information during such tasks, leading some researchers to propose that visual imagery and visual working memory may be one and the same. If visual imagery is essential to visual working memory task performance there should be large ramifications for a special population of individuals who do not experience visual imagery, aphantasia. Here we assessed visual working memory task performance in this population using a number of different lab and clinical working memory tasks. We found no differences in capacity limits for visual, general number or spatial working memory for aphantasic individuals compared to controls. Further, aphantasic individuals showed no significant differences in performance on visual components of clinical working memory tests as compared to verbal components. However, there were significant differences in the reported strategies used by aphantasic individuals across all memory tasks. Additionally, aphantasic individual's visual memory accuracy did not demonstrate a significant oblique orientation effect, which is proposed to occur due to sensory recruitment, further supporting their non-visual imagery strategy reports. Taken together these data demonstrate that aphantasic individuals are not impaired on visual working memory tasks, suggesting visual imagery and working memory are not one and the same, with imagery (and sensory recruitment) being just one of the tools that can be used to solve visual working memory tasks.


Asunto(s)
Imaginación , Memoria a Corto Plazo , Humanos , Imágenes en Psicoterapia , Memoria Espacial , Percepción Visual
20.
Cell Rep ; 36(8): 109554, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34433059

RESUMEN

The human brain consists of specialized areas that flexibly interact to form a multitude of functional networks. Complementary to this notion of modular organization, brain function has been shown to vary along a smooth continuum across the whole cortex. We demonstrate a mathematical framework that accounts for both of these perspectives: harmonic modes. We calculate the harmonic modes of the brain's functional connectivity graph, called "functional harmonics," revealing a multi-dimensional, frequency-ordered set of basis functions. Functional harmonics link characteristics of cortical organization across several spatial scales, capturing aspects of intra-areal organizational features (retinotopy, somatotopy), delineating brain areas, and explaining macroscopic functional networks as well as global cortical gradients. Furthermore, we show how the activity patterns elicited by seven different tasks are reconstructed from a very small subset of functional harmonics. Our results suggest that the principle of harmonicity, ubiquitous in nature, also underlies functional cortical organization in the human brain.


Asunto(s)
Corteza Cerebral/fisiología , Conectoma , Modelos Neurológicos , Femenino , Humanos , Masculino
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