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Keeping in touch with the visual system: spatial alignment and multisensory integration of visual-somatosensory inputs.

Mahoney JR, Molholm S, Butler JS, Sehatpour P, Gomez-Ramirez M, Ritter W, Foxe JJ - Front Psychol (2015)

Bottom Line: In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs.Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms).In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest detectable multisensory integrative effects in response to VS pairings.

View Article: PubMed Central - PubMed

Affiliation: The Cognitive Neurophysiology Laboratory, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg NY, USA ; Division of Cognitive and Motor Aging, Department of Neurology, Albert Einstein College of Medicine, New York NY, USA.

ABSTRACT
Correlated sensory inputs coursing along the individual sensory processing hierarchies arrive at multisensory convergence zones in cortex where inputs are processed in an integrative manner. The exact hierarchical level of multisensory convergence zones and the timing of their inputs are still under debate, although increasingly, evidence points to multisensory integration (MSI) at very early sensory processing levels. While MSI is said to be governed by stimulus properties including space, time, and magnitude, violations of these rules have been documented. The objective of the current study was to determine, both psychophysically and electrophysiologically, whether differential visual-somatosensory (VS) integration patterns exist for stimuli presented to the same versus opposite hemifields. Using high-density electrical mapping and complementary psychophysical data, we examined multisensory integrative processing for combinations of visual and somatosensory inputs presented to both left and right spatial locations. We assessed how early during sensory processing VS interactions were seen in the event-related potential and whether spatial alignment of the visual and somatosensory elements resulted in differential integration effects. Reaction times to all VS pairings were significantly faster than those to the unisensory conditions, regardless of spatial alignment, pointing to engagement of integrative multisensory processing in all conditions. In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs. Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms). In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest detectable multisensory integrative effects in response to VS pairings.

No MeSH data available.


Unisensory ERPs for selected ROIs. (A) Unisensory somatosensory ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. (B) Unisensory visual ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. All axes are the same and the labels are provided in the top left corner.
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Figure 3: Unisensory ERPs for selected ROIs. (A) Unisensory somatosensory ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. (B) Unisensory visual ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. All axes are the same and the labels are provided in the top left corner.

Mentions: Visual inspection of the unisensory somatosensory evoked potentials (SEPs) revealed a robust P60 component emerging at around 30 ms and reaching its peak at ∼65 ms, followed by an N140 component peaking at ∼135 ms over lateral central and posterior scalp sites on the hemisphere contralateral to the stimulated hand (see Figure 3A). These latencies are consistent with other studies that employ vibro-tactile stimuli (see Tobimatsu et al., 1999).


Keeping in touch with the visual system: spatial alignment and multisensory integration of visual-somatosensory inputs.

Mahoney JR, Molholm S, Butler JS, Sehatpour P, Gomez-Ramirez M, Ritter W, Foxe JJ - Front Psychol (2015)

Unisensory ERPs for selected ROIs. (A) Unisensory somatosensory ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. (B) Unisensory visual ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. All axes are the same and the labels are provided in the top left corner.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4525670&req=5

Figure 3: Unisensory ERPs for selected ROIs. (A) Unisensory somatosensory ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. (B) Unisensory visual ERPs for stimuli presented to the right (green traces) and left (blue traces) hemifield. All axes are the same and the labels are provided in the top left corner.
Mentions: Visual inspection of the unisensory somatosensory evoked potentials (SEPs) revealed a robust P60 component emerging at around 30 ms and reaching its peak at ∼65 ms, followed by an N140 component peaking at ∼135 ms over lateral central and posterior scalp sites on the hemisphere contralateral to the stimulated hand (see Figure 3A). These latencies are consistent with other studies that employ vibro-tactile stimuli (see Tobimatsu et al., 1999).

Bottom Line: In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs.Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms).In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest detectable multisensory integrative effects in response to VS pairings.

View Article: PubMed Central - PubMed

Affiliation: The Cognitive Neurophysiology Laboratory, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg NY, USA ; Division of Cognitive and Motor Aging, Department of Neurology, Albert Einstein College of Medicine, New York NY, USA.

ABSTRACT
Correlated sensory inputs coursing along the individual sensory processing hierarchies arrive at multisensory convergence zones in cortex where inputs are processed in an integrative manner. The exact hierarchical level of multisensory convergence zones and the timing of their inputs are still under debate, although increasingly, evidence points to multisensory integration (MSI) at very early sensory processing levels. While MSI is said to be governed by stimulus properties including space, time, and magnitude, violations of these rules have been documented. The objective of the current study was to determine, both psychophysically and electrophysiologically, whether differential visual-somatosensory (VS) integration patterns exist for stimuli presented to the same versus opposite hemifields. Using high-density electrical mapping and complementary psychophysical data, we examined multisensory integrative processing for combinations of visual and somatosensory inputs presented to both left and right spatial locations. We assessed how early during sensory processing VS interactions were seen in the event-related potential and whether spatial alignment of the visual and somatosensory elements resulted in differential integration effects. Reaction times to all VS pairings were significantly faster than those to the unisensory conditions, regardless of spatial alignment, pointing to engagement of integrative multisensory processing in all conditions. In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs. Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms). In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest detectable multisensory integrative effects in response to VS pairings.

No MeSH data available.