Search results for "Stimulus modality"

Multiplicative decomposition of the scaling effect in the Mixed Assessor Model into a descriptor-specific and an overall coefficients

2016

Abstract In 1994, Brockhoff and Skovgaard presented the so-called assessor model, including a “scaling coefficient” expressing the predisposition of a panelist to spread more or less his scores than the panel on a given sensory descriptor. This paper discusses potential scaling causes, and then proposes a decomposition of the scaling coefficient into two components: (i) an overall scaling coefficient, independent of the descriptors, expressing a psychological trend of the panelist towards the scoring task in general; (ii) a corrected scaling coefficient for each descriptor, expressing specific sensitivity of the panelist to the descriptor. Applied to 187 sensory datasets, this decomposition…

A comparative study of sensory processing in children with and without Autism Spectrum Disorder in the home and classroom environments.

2015

Sensory processing and higher integrative functions impairments are highly prevalent in children with ASD. Context should be considered in analyzing the sensory profile and higher integrative functions. The main objective of this study is to compare sensory processing, social participation and praxis in a group of 79 children (65 males and 14 females) from 5 to 8 years of age (M=6.09) divided into two groups: ASD Group (n=41) and Comparison Group (n=38). The Sensory Processing Measure (SPM) was used to evaluate the sensory profile of the children: parents reported information about their children's characteristics in the home environment, and teachers reported information about the same cha…

Timing flickers across sensory modalities

2009

In tasks requiring a comparison of the duration of a reference and a test visual cue, the spatial position of test cue is likely to be implicitly coded, providing a form of a congruency effect or introducing a response bias according to the environmental scale or its vectorial reference. The precise mechanism generating these perceptual shifts in subjective duration is not understood, although several studies suggest that spatial attentional factors may play a critical role. Here we use a duration comparison task within and across sensory modalities to examine if temporal performance is also modulated when people are exposed to spatial distractors involving different sensory modalities. Di…

From spatial acoustic changes to attentive behavioral responses within 200 ms in humans

1999

Human event-related potentials (ERPs) and electro-oculograms (EOGs) were recorded in 14 subjects presented with spatially deviant tones in a series of standard tones. In separate sessions, they were instructed to read a book, to count the deviant tones, and to respond to the deviant tones by shifting the eyes towards them from the standard tone source. When reading a book, the mismatch negativity (MMN) of ERP, reflecting pre-attentive detection of acoustic changes, was elicited to the deviant tones at approximately 105-180 ms. No deviance related EOGs were observed in the reading or counting conditions. When the subjects responded behaviorally to the deviant tones, EOGs revealed that the ey…

Alterations in visual and auditory processing in hemispatial neglect: An evoked potential follow-up study

2010

Hemispatial neglect is common after cerebrovascular stroke in the right hemisphere. Cortical electrophysiological studies, especially investigations of both visual and auditory processing in subjects with neglect are sparse. Our purpose was to assess whether and to which extent subjects with neglect may show impairments in both visual and auditory processing. Thereby, we assessed the evolution of changes in sensory processing and neglect symptoms over a 6 month follow-up period. Twenty-one stroke subjects with hemispatial neglect were studied at baseline, 3 weeks later and at 6 months follow-up. At enrollment, 12 patients were in Acute/subacute and 9 were in the chronic stage of stroke. Vis…

Modeling the insect mushroom bodies: application to a delayed match-to-sample task.

2013

Despite their small brains, insects show advanced capabilities in learning and task solving. Flies, honeybees and ants are becoming a reference point in neuroscience and a main source of inspiration for autonomous robot design issues and control algorithms. In particular, honeybees demonstrate to be able to autonomously abstract complex associations and apply them in tasks involving different sensory modalities within the insect brain. Mushroom Bodies (MBs) are worthy of primary attention for understanding memory and learning functions in insects. In fact, even if their main role regards olfactory conditioning, they are involved in many behavioral achievements and learning capabilities, as …

2013

To identify factors limiting performance in multitone intensity discrimination, we presented sequences of five pure tones alternating in level between loud (85 dB SPL) and soft (30, 55, or 80 dB SPL). In the “overall-intensity task”, listeners detected a level increment on all of the five tones. In the “masking task”, the level increment was imposed only on the soft tones, rendering the soft tones targets and loud tones task-irrelevant maskers. Decision weights quantifying the importance of the five tone levels for the decision were estimated using methods of molecular psychophysics. Compatible with previous studies, listeners placed higher weights on the loud tones than on the soft tones i…

The cortical representation of pain.

1999

Anatomical and physiological studies in animals, as well as functional imaging studies in humans have shown that multiple cortical areas are activated by painful stimuli. The view that pain is perceived only as a result of thalamic processing has, therefore, been abandoned, and has been replaced by the question of what functions can be assigned to individual cortical areas. The following cortical areas have been shown to be involved in the processing of painful stimuli: primary somatosensory cortex, secondary somatosensory cortex and its vicinity in the parietal operculum, insula, anterior cingulate cortex and prefrontal cortex. These areas probably process different aspects of pain in para…

Visual mismatch negativity (vMMN): A review and meta-analysis of studies in psychiatric and neurological disorders

2015

The visual mismatch negativity (vMMN) response is an event-related potential (ERP) component, which is automatically elicited by events that violate predictions based on prior events. VMMN experiments use visual stimulus repetition to induce predictions, and vMMN is obtained by subtracting the response to rare unpredicted stimuli from those to frequent stimuli. One increasingly popular interpretation of the mismatch response postulates that vMMN, similar to its auditory counterpart (aMMN), represents a prediction error response generated by cortical mechanisms forming probabilistic representations of sensory signals. Here we discuss the physiological and theoretical basis of vMMN and review…

Signalling and Reception

2002

Communication, a widespread natural phenomenon, occurs in both animals and plants. Signals are evolved traits that transfer information from one individual (the signaller) to another (the receiver); they can occur in any sensory modality. Keywords: cost and benefits; honesty; mimicry; predation; sexual selection