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Learning-related effects and functional neuroimaging

Petersson, K M ; Elfgren, C LU orcid and Ingvar, M (1999) In Human Brain Mapping 7(4). p.43-234
Abstract

A fundamental problem in the study of learning is that learning-related changes may be confounded by nonspecific time effects. There are several strategies for handling this problem. This problem may be of greater significance in functional magnetic resonance imaging (fMRI) compared to positron emission tomography (PET). Using the general linear model, we describe, compare, and discuss two approaches for separating learning-related from nonspecific time effects. The first approach makes assumptions on the general behavior of nonspecific effects and explicitly models these effects, i.e., nonspecific time effects are incorporated as a linear or nonlinear confounding covariate in the statistical model. The second strategy makes no a priori... (More)

A fundamental problem in the study of learning is that learning-related changes may be confounded by nonspecific time effects. There are several strategies for handling this problem. This problem may be of greater significance in functional magnetic resonance imaging (fMRI) compared to positron emission tomography (PET). Using the general linear model, we describe, compare, and discuss two approaches for separating learning-related from nonspecific time effects. The first approach makes assumptions on the general behavior of nonspecific effects and explicitly models these effects, i.e., nonspecific time effects are incorporated as a linear or nonlinear confounding covariate in the statistical model. The second strategy makes no a priori assumption concerning the form of nonspecific time effects, but implicitly controls for nonspecific effects using an interaction approach, i.e., learning effects are assessed with an interaction contrast. The two approaches depend on specific assumptions and have specific limitations. With certain experimental designs, both approaches may be used and the results compared, lending particular support to effects that are independent of the method used. A third and perhaps better approach that sometimes may be practically unfeasible is to use a completely temporally balanced experimental design. The choice of approach may be of particular importance when learning-related effects are studied with fMRI.

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author
; and
organization
publishing date
type
Contribution to journal
publication status
published
keywords
Adult, Brain Mapping, Conditioning (Psychology), Hippocampus, Humans, Magnetic Resonance Imaging, Male, Mental Recall, Photic Stimulation, Temporal Lobe, Tomography, Emission-Computed, Journal Article, Research Support, Non-U.S. Gov't
in
Human Brain Mapping
volume
7
issue
4
pages
43 - 234
publisher
Wiley-Blackwell
external identifiers
  • scopus:0032970169
  • pmid:10408767
ISSN
1065-9471
DOI
10.1002/(SICI)1097-0193(1999)7:4<234::AID-HBM2>3.0.CO;2-O
language
English
LU publication?
yes
id
e0fc1c52-98e4-4ed9-b308-8104eea6ab7e
date added to LUP
2016-10-29 16:02:32
date last changed
2024-01-04 15:13:17
@article{e0fc1c52-98e4-4ed9-b308-8104eea6ab7e,
  abstract     = {{<p>A fundamental problem in the study of learning is that learning-related changes may be confounded by nonspecific time effects. There are several strategies for handling this problem. This problem may be of greater significance in functional magnetic resonance imaging (fMRI) compared to positron emission tomography (PET). Using the general linear model, we describe, compare, and discuss two approaches for separating learning-related from nonspecific time effects. The first approach makes assumptions on the general behavior of nonspecific effects and explicitly models these effects, i.e., nonspecific time effects are incorporated as a linear or nonlinear confounding covariate in the statistical model. The second strategy makes no a priori assumption concerning the form of nonspecific time effects, but implicitly controls for nonspecific effects using an interaction approach, i.e., learning effects are assessed with an interaction contrast. The two approaches depend on specific assumptions and have specific limitations. With certain experimental designs, both approaches may be used and the results compared, lending particular support to effects that are independent of the method used. A third and perhaps better approach that sometimes may be practically unfeasible is to use a completely temporally balanced experimental design. The choice of approach may be of particular importance when learning-related effects are studied with fMRI.</p>}},
  author       = {{Petersson, K M and Elfgren, C and Ingvar, M}},
  issn         = {{1065-9471}},
  keywords     = {{Adult; Brain Mapping; Conditioning (Psychology); Hippocampus; Humans; Magnetic Resonance Imaging; Male; Mental Recall; Photic Stimulation; Temporal Lobe; Tomography, Emission-Computed; Journal Article; Research Support, Non-U.S. Gov't}},
  language     = {{eng}},
  number       = {{4}},
  pages        = {{43--234}},
  publisher    = {{Wiley-Blackwell}},
  series       = {{Human Brain Mapping}},
  title        = {{Learning-related effects and functional neuroimaging}},
  url          = {{http://dx.doi.org/10.1002/(SICI)1097-0193(1999)7:4<234::AID-HBM2>3.0.CO;2-O}},
  doi          = {{10.1002/(SICI)1097-0193(1999)7:4<234::AID-HBM2>3.0.CO;2-O}},
  volume       = {{7}},
  year         = {{1999}},
}