Decision-related components

The phase of most interest, in terms of identifying particular decision making stages, was the one just prior to the button press, as individuals deliberated about the available, or lack of, information and their commitment to implementing the particular choice. Similar as above, it was important to look at the different conditions individually, before drawing conclusions on the effect they had on their cognitive processing.

Significant differences were observed only in the source located in the occipital lobe, for the congruent and incongruent advice conditions. Again, there were no particular differences between the scenarios at this stage based on visual information. Considering the early activation, especially when overlaid with the response times, this activity most probably related to the presentation of the advice stimuli, and was unrelated to the actual decision-making process.

Considering visual processing, differences were again observed for the source located in the occipital lobe, where the congruent and incongruent conditions resulted in significantly larger amplitudes than the no-advice one. This related directly to the first two including some written information, while the other condition was blank and prompted individuals to shift focus directly to the consideration of their own solution strategy.

Interaction

Of particular interest was the possible interaction between the scenario and advice conditions, further exploring how these affected cognitive processing and which effect they on performance in the forced-choice decision paradigm. Analysis for the activity located in the frontal lobe (S3) showed two particular time intervals where an interaction was observed between the operational conditions.

When looking at the time prior to individuals making a choice (-340ms to - 250ms) recordings showed that the congruent and incongruent advice condition

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resulted in a large positive amplitude in both consequence scenarios. On the other hand, the no-advice condition resulted in a large negative amplitude, but not significantly different when compared between the low- and high-consequence conditions. When considering activity in the same source after individuals’ decision (290ms to 350ms), recordings showed that the type of advice had a significant effect on the high-consequence scenarios, but not on the low-consequence ones. While congruent advice did not affect activity, incongruent advice resulted in a large positive amplitude for the high-consequence condition. On the other hand, the no- advice conditions resulted in a large negative amplitude for the high-consequence ones.

The activity for the meaningful advice corresponded to activity in the dorsolateral prefontral cortex, recognised for its functional involvement in the Stroop Test (Vendrell, Junque, Pujol, Jurado, Molet, & Grafman, 1995; Stuss, Floden, Alexander, Levine, & Katz, 2001). Further, the DLPFC has been identified as playing a key role when solving ill-structured problems (Gilbert, Spengler, Simons, Steele, Lawrie, Frith, & Burgess, 2006), while also recent propositions have suggested that it is involved in strategic processes in memory retrieval and executive functions (Gilbert, Zamenopolous, Alexiou, & Johnson, 2010).

Considering the complex composition of this brain region, the results still provided some insight into the shift observed in terms of cognitive activity. Adding meaningful advice to the decision paradigm resulted in a shift in prioritisation during the task, especially when considering individuals’ qualitative task description and the differences with Experiment 1. In this case, while consequence scenarios had an effect in the conditions where advice information was provided, it did not influence activity prior to the decision. On the other hand, the consequence conditions did affect activity in the same brain area after individuals made their choice, but only for the high-consequence scenarios resulting in significant differences. This pointed to a post-choice consideration, which was not observed for the low-consequence ones. Overall, the set-up of the decision-paradigm pointed to task-relevant information being more important than the consequential context at all stages, while it only seemed to affect activity after the decision was made.

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While the current experiment focused on pre-decisional activity, some of the results pointed to future possibilities relating to post-decision measures. Some differences were observed in the figures for the recordings, with variations in the waveforms immediately after commission to a choice. Analysis in this area should look into possible activation describing feedback preparation and anticipated regret, while also considering potential issues relating to strategy consideration and re- assessment. While the current paradigm did not allow for any confident analysis in this phase, future research would benefit from measures around these areas, to further contribute to the decision-making narrative.

Response Times

In terms of the behavioural measures recorded, identifying activity relating to the stimuli presentation and choice response, results showed that individuals responded in the congruent advice conditions significantly faster than in the incongruent or no-advice ones. While the differences between the congruent and incongruent conditions do fall in line with the findings within the Stroop Test literature (MacLeod, 1991; Rosenfeld & Skogsberg, 2006), response times for the no-advice conditions were significantly longer for one. When looking at the cognitive measures in the no-advice conditions, they showed consistently early activation and differences in terms of shorter engagement in terms of perceptual processing. While no individual source of component stood out, these differences still raised the question why responses were still slower in those conditions, if no additional information was available.

The original expectation of slower response times for the incongruent and no- advice condition was fulfilled, but a subsequent comparison did not yield any clear conclusions. The original goal was to look at the cognitive processing for these two conditions, in order to identify activity relating to the processing of more effortful information (incongruent advice) or the application of problem-solving strategies in the absence of any information (no advice). One suggestion would describe similar response delay for both conditions, but no clear differentiation was possible with the current data. Ultimately, following on from earlier experiments, the aim was to identify redundant deliberation in forced-choice environments, as previously

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observed in situations when lacking any meaningful information. No brain regions were isolated individually for processing facing incongruent or no advice situations, which would have provided a basis on which to further differentiate between cognitive activities.