Lateralized delay period activity marks the focus of spatial attention in working memory

evidence from somatosensory event-related brain potentials

Tobias Katus* (Corresponding Author), Martin Eimer

*Corresponding author for this work

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The short-term retention of sensory information in working memory (WM) is known to be associated with a sustained enhancement of neural activity. What remains controversial is whether this neural trace indicates the sustained storage of information or the allocation of attention. To evaluate the storage and attention accounts, we examined sustained tactile contralateral delay activity (tCDA component) of the event-related potential. The tCDA manifests over somatosensory cortex contralateral to task-relevant tactile information during stimulus retention. Two tactile sample sets (S1, S2) were presented sequentially, separated by 1.5 s. Each set comprised two stimuli, one per hand. Human participants memorized the location of one task-relevant stimulus per sample set and judged whether one of these locations was stimulated again at memory test. The two relevant pulses were unpredictably located on the same hand (stay trials) or on different hands (shift trials). Initially, tCDA components emerged contralateral to the relevant S1 pulse. Sequential loading of WM enhanced the tCDA after S2 was presented on stay trials. On shift trials, the tCDA's polarity reversed after S2 presentation, resulting in delay activity that was now contralateral to the task-relevant S2 pulse. The disappearance of a lateralized neural trace for the relevant S1 pulse did not impair memory accuracy for this stimulus on shift trials. These results contradict the storage account and suggest that delay period activity indicates the sustained engagement of an attention-based rehearsal mechanism. In conclusion, somatosensory delay period activity marks the current focus of attention in tactile WM.

Original languageEnglish
Pages (from-to)6689-6695
Number of pages7
JournalJournal of Neuroscience
Volume35
Issue number17
DOIs
Publication statusPublished - 29 Apr 2015

Fingerprint

Touch
Short-Term Memory
Evoked Potentials
Hand
Brain
Somatosensory Cortex
Information Storage and Retrieval
Retention (Psychology)

Keywords

  • Adult
  • Attention/physiology
  • Electric Stimulation
  • Electroencephalography
  • Evoked Potentials, Somatosensory/physiology
  • Female
  • Functional Laterality/physiology
  • Humans
  • Male
  • Memory, Short-Term/physiology
  • Reaction Time/physiology
  • Somatosensory Cortex/physiology
  • Time Factors
  • Touch

Cite this

@article{826d270a3d54488b89bffbd2617c31bd,
title = "Lateralized delay period activity marks the focus of spatial attention in working memory: evidence from somatosensory event-related brain potentials",
abstract = "The short-term retention of sensory information in working memory (WM) is known to be associated with a sustained enhancement of neural activity. What remains controversial is whether this neural trace indicates the sustained storage of information or the allocation of attention. To evaluate the storage and attention accounts, we examined sustained tactile contralateral delay activity (tCDA component) of the event-related potential. The tCDA manifests over somatosensory cortex contralateral to task-relevant tactile information during stimulus retention. Two tactile sample sets (S1, S2) were presented sequentially, separated by 1.5 s. Each set comprised two stimuli, one per hand. Human participants memorized the location of one task-relevant stimulus per sample set and judged whether one of these locations was stimulated again at memory test. The two relevant pulses were unpredictably located on the same hand (stay trials) or on different hands (shift trials). Initially, tCDA components emerged contralateral to the relevant S1 pulse. Sequential loading of WM enhanced the tCDA after S2 was presented on stay trials. On shift trials, the tCDA's polarity reversed after S2 presentation, resulting in delay activity that was now contralateral to the task-relevant S2 pulse. The disappearance of a lateralized neural trace for the relevant S1 pulse did not impair memory accuracy for this stimulus on shift trials. These results contradict the storage account and suggest that delay period activity indicates the sustained engagement of an attention-based rehearsal mechanism. In conclusion, somatosensory delay period activity marks the current focus of attention in tactile WM.",
keywords = "Adult, Attention/physiology, Electric Stimulation, Electroencephalography, Evoked Potentials, Somatosensory/physiology, Female, Functional Laterality/physiology, Humans, Male, Memory, Short-Term/physiology, Reaction Time/physiology, Somatosensory Cortex/physiology, Time Factors, Touch",
author = "Tobias Katus and Martin Eimer",
note = "This work was supported by the Deutsche Forschungsgemeinschaft Grants KA 3843/1-1 and KA 3843/1-2 and the Economic and Social Research Council, United Kingdom. We thank Anna Grubert, Moran Aharoni, and John Towler for constructive comments on the manuscript, and Sue Nicholas for assistance in setting up the hardware for tactile stimulation.",
year = "2015",
month = "4",
day = "29",
doi = "10.1523/JNEUROSCI.5046-14.2015",
language = "English",
volume = "35",
pages = "6689--6695",
journal = "Journal of Neuroscience",
issn = "0270-6474",
publisher = "Society for Neuroscience",
number = "17",

}

TY - JOUR

T1 - Lateralized delay period activity marks the focus of spatial attention in working memory

T2 - evidence from somatosensory event-related brain potentials

AU - Katus, Tobias

AU - Eimer, Martin

N1 - This work was supported by the Deutsche Forschungsgemeinschaft Grants KA 3843/1-1 and KA 3843/1-2 and the Economic and Social Research Council, United Kingdom. We thank Anna Grubert, Moran Aharoni, and John Towler for constructive comments on the manuscript, and Sue Nicholas for assistance in setting up the hardware for tactile stimulation.

PY - 2015/4/29

Y1 - 2015/4/29

N2 - The short-term retention of sensory information in working memory (WM) is known to be associated with a sustained enhancement of neural activity. What remains controversial is whether this neural trace indicates the sustained storage of information or the allocation of attention. To evaluate the storage and attention accounts, we examined sustained tactile contralateral delay activity (tCDA component) of the event-related potential. The tCDA manifests over somatosensory cortex contralateral to task-relevant tactile information during stimulus retention. Two tactile sample sets (S1, S2) were presented sequentially, separated by 1.5 s. Each set comprised two stimuli, one per hand. Human participants memorized the location of one task-relevant stimulus per sample set and judged whether one of these locations was stimulated again at memory test. The two relevant pulses were unpredictably located on the same hand (stay trials) or on different hands (shift trials). Initially, tCDA components emerged contralateral to the relevant S1 pulse. Sequential loading of WM enhanced the tCDA after S2 was presented on stay trials. On shift trials, the tCDA's polarity reversed after S2 presentation, resulting in delay activity that was now contralateral to the task-relevant S2 pulse. The disappearance of a lateralized neural trace for the relevant S1 pulse did not impair memory accuracy for this stimulus on shift trials. These results contradict the storage account and suggest that delay period activity indicates the sustained engagement of an attention-based rehearsal mechanism. In conclusion, somatosensory delay period activity marks the current focus of attention in tactile WM.

AB - The short-term retention of sensory information in working memory (WM) is known to be associated with a sustained enhancement of neural activity. What remains controversial is whether this neural trace indicates the sustained storage of information or the allocation of attention. To evaluate the storage and attention accounts, we examined sustained tactile contralateral delay activity (tCDA component) of the event-related potential. The tCDA manifests over somatosensory cortex contralateral to task-relevant tactile information during stimulus retention. Two tactile sample sets (S1, S2) were presented sequentially, separated by 1.5 s. Each set comprised two stimuli, one per hand. Human participants memorized the location of one task-relevant stimulus per sample set and judged whether one of these locations was stimulated again at memory test. The two relevant pulses were unpredictably located on the same hand (stay trials) or on different hands (shift trials). Initially, tCDA components emerged contralateral to the relevant S1 pulse. Sequential loading of WM enhanced the tCDA after S2 was presented on stay trials. On shift trials, the tCDA's polarity reversed after S2 presentation, resulting in delay activity that was now contralateral to the task-relevant S2 pulse. The disappearance of a lateralized neural trace for the relevant S1 pulse did not impair memory accuracy for this stimulus on shift trials. These results contradict the storage account and suggest that delay period activity indicates the sustained engagement of an attention-based rehearsal mechanism. In conclusion, somatosensory delay period activity marks the current focus of attention in tactile WM.

KW - Adult

KW - Attention/physiology

KW - Electric Stimulation

KW - Electroencephalography

KW - Evoked Potentials, Somatosensory/physiology

KW - Female

KW - Functional Laterality/physiology

KW - Humans

KW - Male

KW - Memory, Short-Term/physiology

KW - Reaction Time/physiology

KW - Somatosensory Cortex/physiology

KW - Time Factors

KW - Touch

U2 - 10.1523/JNEUROSCI.5046-14.2015

DO - 10.1523/JNEUROSCI.5046-14.2015

M3 - Article

VL - 35

SP - 6689

EP - 6695

JO - Journal of Neuroscience

JF - Journal of Neuroscience

SN - 0270-6474

IS - 17

ER -