Cognitive mechanisms of the defer-speedup and date-delay framing effects in intertemporal choice - data management plan

This data management plan describes a dataset that will be generated to address the following research question: How does the way in which time is described influence intertemporal choice? The dataset will consist of task performance data of a maximum of 192 (but potentially fewer) human participants (one dataset of the defer-speedup framing effect and one dataset of the date-delay framing effect). The approximate total size of this dataset will be less than 1 Gigabyte. This dataset may be useful for behavioral economists, experimental psychologists, and cognitive neuroscientists interested in intertemporal choice and framing effects

Self-reported impulsivity scores (BIS-11) for fall groups.

<p>P values are presented for comparisons between fall groups using the independent samples t-test.</p><p>Cohen’s d indicates effect size (0.2: small effect; 0.5: medium effect; 0.8: large effect).</p

Output parameters of multivariate logistic regression models assessing the association between total impulsivity and fall risk.

<p>Output of logistic regression models controlling for gender, disease severity, dopaminergic medication, and cognitive function. H&Y: Hoehn and Yahr stages. PIGD: Postural instability and gait disability. MMSE: Mini-Mental State Examination. LED: levodopa dose equivalent. ^a LED values were divided by 1000 for these analyses.</p

Cognitive assessment for fall groups.

<p>Mean (sd) values for performance on cognitive tests assessing attention, working memory and fluency are compared between fall groups.</p><p>IDED: Intra- and extradimensional set shift test.</p><p>SWM: Spatial working memory.</p

Demographic and clinical measures for fall groups.

<p>P values of independent t-tests and chi-square are presented to compare fall groups.</p><p>UPDRS-III: Unified Parkinson’s Disease Rating Scale motor examination; PIGD: Postural Instability and Gait Disability; MMSE: Mini-Mental State Examination; LED: Levodopa Equivalent Dose. DA: dopamine.</p

Output parameters of multivariate logistic regression models assessing the association between attentional impulsivity and fall risk.

<p>Output of logistic regression models controlling for gender, disease severity, dopaminergic medication, and cognitive function. H&Y: Hoehn and Yahr stages. PIGD: Postural instability and gait disability. MMSE: Mini-Mental State Examination. LED: levodopa dose equivalent. ^a LED values were divided by 1000 for these analyses.</p

Time-frequency dynamics of cortico-striatal interactions between nucleus accumbens (NAc) and frontal cortex (FC).

<p><b>A</b> Time-frequency coherence spectrum. In the prestimulus period (-1000 ms to 0 ms), both alpha and theta band coherence were strong. After stimulus onset (0 ms), alpha band coherence decreased while theta band coherence increased. <b>B</b> Granger causality from frontal electrodes to nucleus accumbens was highest in the alpha range (9–14 Hz) and diminished upon stimulus processing (after 0 ms). <b>C</b> Granger causality from nucleus accumbens to frontal electrodes was strongest in the theta range and increased upon stimulus processing (after 0 ms).</p

Granger causality values for the theta- and the alpha-band in the two directions calculated for the full time interval (-1 to 0.5 s).

<p>The solid line indicates the main diagonal to help illustrating in how many participants the Granger results were stronger in the one compared to the other direction A In half of the subjects, theta-band oscillations were stronger from cortex to nucleus accumbens (NAc) than the other way around. B Alpha-band oscillations were stronger from the cortex to the nucleus accumbens than from nucleus accumbens to the cortex for five out of six subjects (permutation test across subjects, p<0.05). This indicates that cortical alpha-band activity granger-cause activity in the nucleus accumbens.</p

The paradigm.

<p>The attended side was initially indicated by a cue. Subjects had to fixate at the central cross and by button press indicate the color of the attended squares (left button for red and right button for blue). The 1200 ms prestimulus period was followed by the colored stimuli flashed for 33 ms. Subjects had to respond within 2500 ms. If there was a color change in the square of the unattended hemifield, attention had to switch to that direction (‘switch-trial). After the response there was a 1000 ms window for eye blinking. A Example of an explicit cue followed by a repeat trial. The subject had to covertly attend to the left and subsequently report the color of the stimuli by pressing the corresponding button (here: blue, right button). B Example of a switch trial. In the previous repeat trials, the subject had to attend to the left, because of the initially shown spatial cue. Upon stimulus presentation, the subject correctly switched attention and indicated so by reporting the color of the stimulus at the formerly unattended side (here: right, red color). If the subject responded according to the formerly attended side (here: left, blue), the switch trial would repeat up to four times. Repetitions of switch trials were removed from the analysis. If the subject did not switch after the fourth consecutive switch trial, another explicit spatial cue pointing to the formerly unattended side was presented (here: a rightward pointing arrow).At the beginning of each block, subjects were explicitly cued to which side to attend. From then on, the attended side was determined by stimuli properties alone. A central fixation point was presented during the entire experiment. Colored squares were flashed 1200ms after the beginning of each trial for about 33 ms (two frames = 2/60Hz). These stimuli were presented with six degrees eccentricity and two degrees lower than the fixation cross (measured from the fixation cross to the center of the stimuli). The squares were two degrees wide.</p

Significant interaction effects of the factorial ANOVA on the Granger estimates.

<p><b>A</b> The <i>time</i> by <i>frequency</i> interaction (F(1, 5) = 20.92, p<0.01, Cohen’sf = 0.17) indicates that there was a significant theta band increase poststimulus compared to prestimulus Granger causality (t(5) = 3.52, p<0.05). No such change was present in the alpha-band. In the poststimulus window, Granger causality in the theta band was significantly stronger than in the alpha band (t(5) = 4.27, p<0.01). <b>B</b> The ANOVA showed a significant frequency by directionality interaction (F(1, 5) = 9.68, p<0.05, Cohen’s f = 0.17). In post-hoc tests, we found that the granger-causal influence from nucleus accumbens on cortex was stronger in the theta-band than in the alpha-band (t(5) = 4.84, p<0.01). In contrast, there was no significant difference in Granger causality in the alpha-band between cortex-to-nucleus accumbens and nucleus accumbens-to-cortex direction (t(5) = 1.75, p = 0.14). However, for five out of six subjects Granger estimates in the alpha-band were stronger for the cortex-to-nucleus accumbens direction than the other way around (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138685#pone.0138685.g005" target="_blank">Fig 5</a>). Data are represented as mean ± SEM. * = p<0.05, ** = p<0.01. = p<0.01.</p