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1.
Conscious Cogn ; 112: 103533, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37263078

RESUMEN

Metacognition is the process by which we know what we know. Knowing has both declarative and sensed components. Differences exist in the information that moves to our conscious awareness and how it is synthesised with existing knowledge. The current study measured metacognition by extending a visual change detection paradigm that promoted explicit or implicit detection by either a local or global manipulation of a scene. A within-subjects design was used to investigate how 91 participants detected change and made metacognitive judgements. Cognitive modelling, based on confidence judgements, estimated the relative contributions of discrete and continuous cognitive processes to change detection, and to metacognition. Metacognition was sensitive to both the discrete and continuous processes underlying change detection, but was more sensitive to the discrete process. These results demonstrate that metacognition attunes confidence differentially to explicit and implicit processes, and support direct-access theories for discrete processing and meta-representation theories for continuous processing.


Asunto(s)
Metacognición , Humanos , Juicio
2.
J Sex Med ; 19(7): 1073-1089, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35422400

RESUMEN

BACKGROUND: Over the past 30 years, functional magnetic resonance imaging (fMRI) has emerged as a powerful tool to non-invasively study the activity and function of the human brain. But along with the potential of fMRI to shed light on neurological, psychiatric, and psychological processes, there are methodological challenges and criticisms. AIM: We herein provide an fMRI primer designed for a diverse audience, from the neuroimaging novice to the experienced user. METHODS: This primer is structured as follows: Part 1: Overview: "What is fMRI and what can it tell us?." Part 2: Basic fMRI principles: MR physics, the BOLD signal, and components of a typical scan session. Part 3: Basic fMRI experimental design: why timing is critical, and common sources of noise in the signal. Part 4: Basic fMRI analysis methods: software, the 3 stages of data analysis (preprocessing, individual, and group level), and a survey of advanced topics and methods including connectivity, machine learning, and assessing statistical significance. Part 5: Criticism, crises, and opportunities related to power of studies, computing requirements, logistical, and interpretational challenges, and methodological debate (assessing causality, circular correlations, and open science best practices). OUTCOMES N/A CLINICAL TRANSLATION: fMRI has primarily been used in clinical research to elucidate the brain correlates of sexual behavior. The translational potential of the method into clinical practice has not yet been realizedfMRI has primarily been used in clinical research to elucidate the brain correlates of sexual behavior. The translational potential of the method into clinical practice has not yet been realized STRENGTHS AND LIMITATIONS: fMRI is a useful and powerful tool for understanding the brain basis of human sexuality. However, it is also expensive, requires extensive methods expertise, and lacks the precision needed to be immediately translatable to clinical practice. The recency of the method, need for basic research, technical limitations, as well as inherent variability in individuals brain activity also impact the pace at which fMRI for sexual medicine can move from the scanner to the clinic. CONCLUSION: This primer provides the novice an understanding of the appropriate uses and limitations of fMRI, and for the experienced user, a concise update on current issues and methodological advances. Mills-Finnerty C, Frangos E, Allen K, et al. Functional Magnetic Resonance Imaging Studies in Sexual Medicine: A Primer. J Sex Med 2022;19:1073-1089.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética/métodos , Conducta Sexual
3.
J Sex Med ; 17(4): 603-613, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31953029

RESUMEN

INTRODUCTION: The projection of the human male urogenital system onto the paracentral lobule has not previously been mapped comprehensively. AIM: To map specific urogenital structures onto the primary somatosensory cortex toward a better understanding of sexual response in men. METHODS: Using functional magnetic resonance imaging, we mapped primary somatosensory cortical responses to self-stimulation of the penis shaft, glans, testicles, scrotum, rectum, urethra, prostate, perineum, and nipple. We further compared neural response with erotic and prosaic touch of the penile shaft. MAIN OUTCOME MEASURE: We identified the primary mapping site of urogenital structures on the paracentral lobule and identified networks involved in perceiving touch as erotic. RESULTS: We mapped sites on the primary somatosensory cortex to which components of the urogenital structures project in men. Evidence is provided that penile cutaneous projection is different from deep penile projection. Similar to a prior report in women, we show that the nipple projects to the same somatosensory cortical region as the genitals. Evidence of differential representation of erotic and nonerotic genital self-stimulation is also provided, the former activating sensory networks other than the primary sensory cortex, indicating a role of "top-down" activity in erotic response. CLINICAL IMPLICATIONS: We map primary sites of projection of urogenital structures to the primary somatosensory cortex and differentiate cortical sites of erotic from nonerotic genital self-stimulation. STRENGTH & LIMITATIONS: To our knowledge, this is the first comprehensive mapping onto the primary somatosensory cortex of the projection of the components of the urogenital system in men and the difference in cortical activation in response to erotic vs nonerotic self-stimulation. The nipple was found to project to the same cortical region as the genitals. Evidence is provided that superficial and deep penile stimulation project differentially to the cortex, suggesting that sensory innervation of the penis is provided by more than the (pudendal) dorsal nerve. CONCLUSION: This study reconciles prior apparently conflicting findings and offers a comprehensive mapping of male genital components to the paracentral lobule. We provide evidence of differential projection of light touch vs pressure applied to the penile shaft, suggesting differential innervation of its superficial, vs deep structure. Similar to the response in women, we found nipple projection to genital areas of the paracentral lobule. We also provide evidence of differential representation of erotic and nonerotic genital self-stimulation, the former activating sensory networks other than the primary sensory cortex, indicating a role of top-down activity in erotic response. Allen K, Wise N, Frangos E, et al. Male Urogenital System Mapped Onto the Sensory Cortex: Functional Magnetic Resonance Imaging Evidence. J Sex Med 2020;17:603-613.


Asunto(s)
Mapeo Encefálico/métodos , Genitales/fisiología , Imagen por Resonancia Magnética , Pene/fisiología , Adulto , Literatura Erótica/psicología , Humanos , Masculino , Persona de Mediana Edad , Pene/inervación , Escroto/fisiología , Adulto Joven
4.
Brain Res ; 1707: 184-189, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30500402

RESUMEN

Previous studies in animals and humans suggest the periaqueductal grey region (PAG) is a final integration station between the brain and laryngeal musculature during phonation. To date, a limited number of functional magnetic neuroimaging (fMRI) studies have examined the functional connectivity of the PAG during volitional human phonation. An event-related, stimulus-induced, volitional movement paradigm was used to examine neural activity during sustained vocalization in neurologically healthy adults and was compared to controlled exhalation through the nose. The contrast of vocalization greater than controlled expiration revealed activation of bilateral auditory cortex, dorsal and ventral laryngeal motor areas (dLMA and vLMA) (p < 0.05, corrected), and suggested activation of the cerbellum, insula, dorsomedial prefrontal cortex (dmPFC), amygdala, and PAG. The functionally defined PAG cluster was used as a seed region for psychophysiological interaction analysis (PPI) to identify regions with greater functional connectivity with PAG during volitional vocalization, while the above functionally defined amygdala cluster was used in an ROI PPI analysis. Whole-brain results revealed increased functional connectivity of the PAG with left vLMA during voicing, relative to controlled expiration, while trend-level evidence was observed for increased PAG/amygdala coupling during voicing (p = 0.07, uncorrected). Diffusion tensor imaging (DTI) analysis confirmed structural connectivity between PAG and vLMA. The present study sheds further light on neural mechanisms of volitional vocalization that include multiple inputs from both limbic and motor structures to PAG. Future studies should include investigation of how these neural mechanisms are affected in individuals with voice disorders during volitional vocalization.


Asunto(s)
Vías Nerviosas/fisiología , Sustancia Gris Periacueductal/fisiología , Fonación/fisiología , Adulto , Encéfalo/fisiología , Mapeo Encefálico/métodos , Imagen de Difusión Tensora/métodos , Femenino , Voluntarios Sanos , Humanos , Laringe/fisiología , Sistema Límbico/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Pliegues Vocales/inervación , Pliegues Vocales/fisiología
5.
J Speech Lang Hear Res ; 61(3): 496-509, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29466555

RESUMEN

Purpose: Musical training is often linked to enhanced auditory discrimination, but the relative roles of pitch and time in music and speech are unclear. Moreover, it is unclear whether pitch and time processing are correlated across individuals and how they may be affected by attention. This study aimed to examine pitch and time processing in speech and tone sequences, taking musical training and attention into account. Method: Musicians (16) and nonmusicians (16) were asked to detect pitch or timing changes in speech and tone sequences and make a binary response. In some conditions, the participants were focused on 1 aspect of the stimulus (directed attention), and in others, they had to pay attention to all aspects at once (divided attention). Results: As expected, musicians performed better overall. Performance scores on pitch and time tasks were correlated, as were performance scores for speech and tonal stimuli, but most markedly in musicians. All participants performed better on the directed versus divided attention task, but again, musicians performed better than nonmusicians. Conclusion: In general, this experiment shows that individuals with a better sense of pitch discrimination also have a better sense of timing discrimination in the auditory domain. In addition, although musicians perform better overall, these results do not support the idea that musicians have an added advantage for divided attention tasks. These findings serve to better understand how musical training and attention affect pitch and time processing in the context of speech and tones and may have applications in special populations. Supplemental Material: https://doi.org/10.23641/asha.5895997.


Asunto(s)
Atención , Aprendizaje , Música , Percepción de la Altura Tonal , Percepción del Habla , Percepción del Tiempo , Adulto , Discriminación en Psicología , Femenino , Humanos , Masculino , Competencia Profesional , Adulto Joven
6.
Brain Lang ; 123(3): 174-82, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23010489

RESUMEN

All linguistic and psycholinguistic theories aim to provide psychologically valid analyses of particular grammatical patterns and the relationships that hold among them. Until recently, no tools were available to distinguish neural correlates of particular grammatical constructions that shared the same content words, propositional meaning, and degree of surface complexity, such as the dative (e.g., Sally gave the book to Joe) and the ditransitive (e.g., Sally gave Joe a book). We report the first fMRI data that distinguish such closely related, abstract grammatical patterns. Multi-voxel pattern analysis (MVPA) proved capable of discriminating at above-chance levels between activity patterns arising during reading of dative and ditransitive sentences. Region-of-interest analyses reveal that the union of certain language-relevant areas, anterior and posterior BA22, BA44/45 and BA47, yield classification accuracy above chance and above that of control conditions in the left hemisphere but not in the right. Looking more closely at the LH ROIs, we find that the combination of areas aBA22 and BA47 is sufficient to distinguish the two constructions better than the controls and better than chance. The fact that both of these areas-particularly BA47-have been implicated in semantics, lends support to claims that the two constructions are distinguishable semantically. More generally, the ability to distinguish closely related grammatical constructions using MVPA offers the promise of addressing traditional theoretical questions on a neuroscientifically grounded basis.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Femenino , Humanos , Lenguaje , Imagen por Resonancia Magnética , Masculino , Adulto Joven
7.
Front Psychol ; 3: 49, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22435061

RESUMEN

A new collection of pseudo-words was recorded from a single female speaker of American English for use in multi-talker speech intelligibility research. The pseudo-words (known as the KARG collection) consist of three groups of single syllable pseudo-words varying only by the initial phoneme. The KARG method allows speech intelligibility to be studied free of the influence of shifts of spatial attention from one loudspeaker location to another in multi-talker contexts. To achieve this, all KARG pseudo-words share the same concluding rimes, with only the first phoneme serving as a distinguishing identifier. This ensures that listeners are unable to correctly identify the target pseudo-word without hearing the initial phoneme. As the duration of all the initial phonemes are brief, much shorter than the time required to spatially shift attention, the KARG method assesses speech intelligibility without the confound of shifting spatial attention. The KARG collection is available free for research purposes.

8.
J Acoust Soc Am ; 130(4): 2043-53, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21973359

RESUMEN

In many natural settings, spatial release from masking aids speech intelligibility, especially when there are competing talkers. This paper describes a series of three experiments that investigate the role of prior knowledge of masker location on phoneme identification and spatial release from masking. In contrast to previous work, these experiments use initial stop-consonant identification as a test of target intelligibility to ensure that listeners had little time to switch the focus of spatial attention during the task. The first experiment shows that target phoneme identification was worse when a masker played from an unexpected location (increasing the consonant identification threshold by 2.6 dB) compared to when an energetically very similar and symmetrically located masker came from an expected location. In the second and third experiments, target phoneme identification was worse (increasing target threshold levels by 2.0 and 2.6 dB, respectively) when the target was played unexpectedly on the side from which the masker was expected compared to when the target came from an unexpected, symmetrical location in the hemifield opposite the expected location of the masker. These results support the idea that listeners modulate spatial attention by both focusing resources on the expected target location and withdrawing attentional resources from expected locations of interfering sources.


Asunto(s)
Ruido/efectos adversos , Enmascaramiento Perceptual , Localización de Sonidos , Inteligibilidad del Habla , Percepción del Habla , Estimulación Acústica , Adulto , Atención , Audiometría del Habla , Umbral Auditivo , Señales (Psicología) , Femenino , Humanos , Masculino , Fonética , Reconocimiento en Psicología , Detección de Señal Psicológica , Incertidumbre
9.
J Sex Med ; 8(10): 2822-30, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21797981

RESUMEN

INTRODUCTION: The projection of vagina, uterine cervix, and nipple to the sensory cortex in humans has not been reported. AIMS: The aim of this study was to map the sensory cortical fields of the clitoris, vagina, cervix, and nipple, toward an elucidation of the neural systems underlying sexual response. METHODS: Using functional magnetic resonance imaging (fMRI), we mapped sensory cortical responses to clitoral, vaginal, cervical, and nipple self-stimulation. For points of reference on the homunculus, we also mapped responses to the thumb and great toe (hallux) stimulation. MAIN OUTCOME MEASURES: The main outcome measures used for this study were the fMRI of brain regions activated by the various sensory stimuli. RESULTS: Clitoral, vaginal, and cervical self-stimulation activated differentiable sensory cortical regions, all clustered in the medial cortex (medial paracentral lobule). Nipple self-stimulation activated the genital sensory cortex (as well as the thoracic) region of the homuncular map. CONCLUSION: The genital sensory cortex, identified in the classical Penfield homunculus based on electrical stimulation of the brain only in men, was confirmed for the first time in the literature by the present study in women applying clitoral, vaginal, and cervical self-stimulation, and observing their regional brain responses using fMRI. Vaginal, clitoral, and cervical regions of activation were differentiable, consistent with innervation by different afferent nerves and different behavioral correlates. Activation of the genital sensory cortex by nipple self-stimulation was unexpected, but suggests a neurological basis for women's reports of its erotogenic quality.


Asunto(s)
Encéfalo/fisiología , Cuello del Útero/inervación , Clítoris/inervación , Imagen por Resonancia Magnética , Vagina/inervación , Adulto , Mapeo Encefálico , Cuello del Útero/fisiología , Clítoris/fisiología , Femenino , Humanos , Persona de Mediana Edad , Sensación/fisiología , Vagina/fisiología , Adulto Joven
10.
Psychol Sci ; 21(10): 1518-24, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20855906

RESUMEN

Linguistic theory holds that the structure of a sentence can be described in abstract syntactic terms, independent of the specific words the sentence contains. Nonlinguistic behavior, including goal-directed action, is also theorized to have an underlying structural, or "syntactic," organization. We propose that purposive action sequences are represented cognitively in terms of a means-ends parse, which is a formal specification of how actions fit together to accomplish desired outcomes. To test this theory, we leveraged the phenomenon of structural priming in two experiments. As predicted, participants read sentences describing action sequences faster when these sentences were presented amid other sentences sharing the same parse. Results from a second experiment indicate that the underlying representations relevant to observed action sequences are not strictly tied to language processing. Our results suggest that the structure of goal-directed behavior may be represented abstractly, independently of specific actions and goals, just as linguistic syntax is thought to stand independent of other levels of representation.


Asunto(s)
Comprensión , Formación de Concepto , Objetivos , Imaginación , Lectura , Adolescente , Adulto , Atención , Señales (Psicología) , Femenino , Humanos , Masculino , Memoria a Corto Plazo , Reconocimiento Visual de Modelos , Psicolingüística , Tiempo de Reacción , Semántica , Grabación en Video , Adulto Joven
11.
Atten Percept Psychophys ; 71(1): 164-73, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19304606

RESUMEN

Speech reception thresholds (SRTs) were measured at a central focus of attention and at 20 degrees, 40 degrees, and 60 degrees locations distant in azimuth. Measurements were taken with one target collocated with two maskers, or with maskers flanking the target by +/-20 degrees. For 80% of trials, the target was played from the attended location ("expected"), and 20% came from another ("unexpected") location. For collocated stimuli, SRTs worsened with increasing distance from the expected location by 2.1 dB over the 60 degrees azimuth and by 5.1 dB for spatially separated target and maskers. In spatially separated conditions, a 2.9-dB change was still found when gaze was away from the attended location. Spatial attention appears to increase speech intelligibility against interferers, with gain decreasing with distance from the focus of attention. Spatial release from masking (RFM) was only found for the attended location. Further experiments suggest that target location uncertainty prevented RFM at unattended locations.


Asunto(s)
Atención , Orientación , Percepción del Habla , Prueba del Umbral de Recepción del Habla , Adulto , Femenino , Humanos , Enmascaramiento Perceptual , Localización de Sonidos
12.
J Acoust Soc Am ; 123(3): 1562-70, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18345844

RESUMEN

To examine whether auditory streaming contributes to unmasking, intelligibility of target sentences against two competing talkers was measured using the coordinate response measure (CRM) [Bolia et al., J. Acoust. Soc. Am. 107, 1065-1066 (2007)] corpus. In the control condition, the speech reception threshold (50% correct) was measured when the target and two maskers were collocated straight ahead. Separating maskers from the target by +/-30 degrees resulted in spatial release from masking of 12 dB. CRM sentences involve an identifier in the first part and two target words in the second part. In experimental conditions, masking talkers started spatially separated at +/-30 degrees but became collocated with the target before the scoring words. In one experiment, one target and two different maskers were randomly selected from a mixed-sex corpus. Significant unmasking of 4 dB remained despite the absence of persistent location cues. When same-sex talkers were used as maskers and target, unmasking was reduced. These data suggest that initial separation may permit confident identification and streaming of the target and masker speech where significant differences between target and masker voice characteristics exist, but where target and masker characteristics are similar, listeners must rely more heavily on continuing spatial cues.


Asunto(s)
Umbral Auditivo , Percepción Espacial , Conducta Espacial , Habla , Adulto , Femenino , Humanos , Masculino , Enmascaramiento Perceptual/fisiología , Prueba del Umbral de Recepción del Habla
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