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Eye-tracking: As can be seen, the graph (Fig. 3.3) shows an overall preference for looking at the recent target relative to the future target throughout the Verb and until the middle of the Adverb region. Participants inspected the recent tar-get object for about 1900 ms from the Verb onset onward in both tense sentence conditions. During most of this period the log ratio for both the past and future conditions remains well above zero (indicating that the recent target receives more looks than the future target). Interestingly, in the beginning of the Verb prefer-ential inspections towards the recent event target increased rapidly 400 ms after the Verb onset and the preferential inspection towards the recent target lasted throughout the Verb region. Listeners increased eye-movements towards the re-cent event target occurred irrespective of tense and despite the strong frequency bias towards future events. Importantly though, the two lines began to separate towards the end of the Verb region, which shows an earlier effect than in the ex-periment with balanced proportion of future and recent events (Knoeferle et al., 2001, Exp. 2). When participants hear the Verb in the future tense condition at the end of the Verb region they decrease their gaze toward the recent target. From the middle of the Adverb region participants inspected the future target object in the future tense condition more than in the past tense condition and correspond-ingly they looked more towards the recent target object in the past than future tense condition. This pattern increases steadily throughout the Adverb and the NP2 region. In the NP2 region, the future target is clearly preferred to the past target in the future tense condition (the log ratio is negative, -.926) throughout this region (see Table 3.2). The main finding, however is that despite the strong frequency bias toward the future condition and despite the earlier inspection of the future event target (by approximately 1000 ms compared with Experiment 2 by Knoeferle et al., 2011), the grand mean (see Table 3.2) in the present experiment

remained positive in all three regions, indicating an overall preference towards the recent event target.

Figure 3.3: Mean log gaze probability ratios (ln (P(recent target/P(future tar-get))) by condition from verb onset, Experiment 1

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Table 3.2: Grand mean and mean log gaze probability ratios (ln (P(recent target)/P (future target)) by participants as a function of condition and time region for the experiment. Standard errors (SE) in parentheses, Experiment 1

Regions Future tense Past tense Grand mean Verb .494 (.15) .969 (.24) .73 (.15)

Adv .353 (.21) 2.13 (.23) 1.24 (.17) NP2 -.926 (.17) 1.93 (.23) .50 (.12)

We now turn to present the inferential analyses. Importantly, the conclusions emerging from the descriptive analyses above were mostly corroborated by the inferential analyses of the data. While the log ratio showed a positive value in all three regions in the time course presentation, the inferential analyses supported this with significant intercepts in all three regions by participants and items ps

< .000 (see Table 3.3). For the Verb region, the ANOVA showed a marginal tense effect by participants F 1(df =1.31) = 3.18, p1 = .084 and a significant effect by items F 2(df =1.23) = 11.48, p2 = .003. This study replicated a not fully significant effect of tense for the Verb region, much like previous studies (i.e., Knoeferle, Carminati, et al., 2011). Importantly though, we can see that there is a significant tense effect in the Adverb and NP2 regions. The tense effect in the Adverb region was reliable by participants F 1(df =1.31) = 16.24, p1 = .000

and by items F 2(df =1.23) = 54.66, p2 = .000. The NP2 region further shows a reliable tense effect by participants F 1(df =1.31) = 73.26, p1 = .000 and by items F 2(df =1.23) = 163.51, p2 = .000 (see Table 3.3). Overall, the results revealed that participants made more inspections to the recent than future target object in the past tense than in the future tense conditions. This effect was reliable in all analyses (except by subjects in the Verb region).

On the one hand, the significant intercept in all three regions could be due to a possible epistemic bias towards the recent event target. We hypothesised that if the epistemic bias exists, participants might inspect the recent event target more even with a strong frequency bias in favor of future events. However, on the other hand, the frequency distribution (75/25%) in the present experiment revealed its effectiveness and resulted in an earlier inspection of the future event target (approximately 1000 ms earlier than in experiment 2 by Knoeferle et al., 2011, when frequency of recent and future events was balanced). Furthermore, the present manipulation revealed a fully significant tense effect in the Adverb and NP2 regions (but only a marginal tense effect by participants in the Verb region).

Table 3.3: ANOVA analyses for the data of Experiment by region: The inter-cept is also given because in this case a significant interinter-cept indicates that the

grand mean is significantly different from 0, Experiment 1

Regions Effect F1 (df=1,31) F2 (df=1,23) P1 P2

Verb Intercept 23.20 44.66 .000 .000

tense 3.18 11.48 .084 .003

Adv Intercept 52.57 66.19 .000 .000

tense 16.24 54.66 .000 .000

NP2 Intercept 16.51 14.88 .000 .001

tense 73.26 163.51 .000 .000

Further, the t -tests presented in table 3.4 reveal that the means in the Verb and Adverb regions are positive (indicating a preference for the recent target, which was reliable in the Verb region only). The means are negative in the NP2 region and the effect is significant but reversed (indicating a preference now for the future target). While the significant effect in the Verb region confirms the robustness of the recent-event preference, the effect in the NP2 regions affirm the effect of the frequency bias.

Table 3.4: One-sample two-tailed t-tests on the mean log ratios by word region for the future condition, Experiment 1

Regions t1 (df=1,31) t2 (df=1,23) P1 P2

Verb 3.28 3.76 .003 .001

Adv 1.69 1.03 .102 .310

NP2 -5.28 -6.14 .000 .000

Memory test: Figure 3.4 shows the percentage of correct answers, averaged by con-dition (by participants). Participants correctly answered 82.5% of the questions.

As can be seen from the graph, participants were more accurate in recognizing the recent action events than the future action events (85.5% vs. 79.5%).

Figure 3.4: Percentage of correct answers as a function of object and tense

68   70   72   74   76   78   80   82   84   86   88  

Future event Recent event

Percentage of correct answers

Experiment 1

Past Future

Table 3.5: Linear mixed effect model results for the memory test, Experiment 1

Effects Coefficient SE z-Value P

Intercept 1.98 0.19 11.01 .000

Object 0.21 0.16 1.28 .200

Tense -0.12 0.17 -0.74 .460

Object x Tense 0.12 0.13 0.97 .330

Further LME analyses on the data from the memory test revealed that neither the main effects (of tense or event) nor their interaction was reliable. Even though

the data visually showed a difference, that difference was thus not confirmed by the inferential analyses. Perhaps then, the recent events are remembered better because they were fixated more than the future action events. Interestingly, this goes against the recency effect hypothesis, which should have resulted in better recognition of the future action events. In contrast, the short-term memory seems to be in line with the gaze data: the objects that are inspected more are also recalled better.

Summary

Even though with the current frequency distribution we showed evidence of an ear-lier gaze shift towards the future event target object in the future tense sentences than in experiment 2 with 50/50% byKnoeferle, Carminati, et al.(2011), surpris-ingly however, the recent-event preference has been replicated. We expected an early future event target inspection from the end of the future tense verb in the fu-ture tense condition. Contrary to our expectations participants shifted their gaze to the future target only from the middle of the Adverb region. That is around 700 ms after the verb offset. Moreover, the overall recent event target preference emerged in all three sentence regions (the verb, if only by items; the adverb, and the NP2 regions). The memory test findings with a better recognition of the recent action events supports the findings of the eye-tracking study.

It is not clear why the shift of visual attention to the future target object did not occur even earlier (given the strong 75%-25% frequency distribution). One reason could be that participants preferred to inspect the recent event target because they have always seen the recent action before the sentence. Thus, in spite of a strong tense cue, recently perceived action events seem to have a strong influence on anticipating objects in the scene. The next experiment investigates this question by further increasing the number of future events and future tense sentences and additionally by decreasing the number of the recent action events.