Testing cognitive models of decision-making: selected studies with starlings

The behavioural sciences are home to controversies that have survived for centuries, notably about the relation between observable behaviour and theoretical constructs addressing out-of-sight processes in the agents' brains. There is no shared definition for cognition, but the very existence of a thriving journal called Animal Cognition proves that such controversies are still live and help to (a) promote research on the complexity of processes leading to action, and (b) nudge scholars to restrict their cognitive models to those that can be falsified experimentally. Here, we illustrate some of these issues in a limited arena, focusing on the construction and expression of subjective value and choice. Using mainly work from our own laboratory, we show that valuation of alternatives is sensitive to options' properties, to subject's state, and to background alternatives. These factors exert their influence at the time the subject learns about individual options, rather than at choice time. We also show that valuation can be experimentally dissociated from the cognitive representation of options' metrics and argue that experimental animals process options independently at the time of choice, without elaborated comparisons along different dimensions. The findings we report are not consistent with the hypothesis that preference is constructed at the time of choice, a prevalent view in human decision-making research. We argue that animal cognition, viewed as a research program at the crossroads of different behavioural sciences rather than as a debate about properties of mental life, is inspiring and solid, and a progressive and progressing paradigm.

Flash Visual Evoked Potentials in Conscious Horses: A Preliminary Study

The visual evoked potential (VEP) has many applications in veterinary neurology, but the test is not routinely used in a clinical setting. The aim of this study was to describe a reliable method for recording flash visual evoked potentials (F-VEPs) in nonsedated horses. F-VEPs were recorded from both eyes in 20 healthy and calm, adult horses. Recordings were accomplished without sedation, anaesthesia, or the use of mydriatic drugs. The mean and standard deviation of the latency of the most evident positive peak was 52.76±2.37 ms (P53). The mean latencies of the preceding and following negative peaks were 38.14±4.62 (N38) and 72.35±5.33 ms (N72), respectively. There were 2 mean peak-to-peak amplitudes (N38 - P53 and P53 - N72), and they were 11.85±6.21 and 22.81±11.50 µV, respectively. F-VEP was also recorded from 3 horses (6 eyes) before and during sedation with 2 doses each of xylazine (0.4 and 1.1 mg/kg) or detomidine (0.005 and 0.014 mg/kg). It was possible to obtain a reliable F-VEP with a P53 latency in horses without sedation that was similar to the P2 peak described in previous studies, and these data can be used in the future as a normal reference for comparisons in horses with different diseases using a similar methodology. Sedation affected the results by depressing peak amplitudes and increasing latencies or by completely obscuring any response. The exact impact of sedation on VEPs must be evaluated with much caution due to the small sample size.

Evaluating metrics in link streams

We seek to understand the topological and temporal nature of temporal networks by computing the distances, latencies and lengths of shortest fastest paths. Shortest fastest paths offer interesting insights about connectivity that were unknowable until recently. Moreover, distances and latencies tend to be computed by separate algorithms. We developed four algorithms that each compute all those values efficiently as a contribution to the literature. Two of those methods compute metrics from a fixed source temporal node. The other two, as a significant contribution to the literature, compute the metrics between all pairs of source and destination temporal nodes. The methods are also grouped by whether they work on paths with delays or not. Proofs of correctness for our algorithms are presented as well as bounds on their temporal complexities as functions of temporal network parameters. Experimental results show the algorithms presented perform well against the state of the art and terminate in decent time on real-world datasets. One purpose of this study is to help develop algorithms to compute centrality functions on temporal networks such as the betweenness centrality and the closeness centrality.

The functional equivalence of two variants of the suboptimal choice task: choice proportion and response latency as measures of value

In the suboptimal-choice task, birds systematically choose the leaner but informative option (suboptimal) over the richer but non-informative option (optimal). The task has two variations. In the standard task, the optimal option includes two terminal link stimuli. In the original task, it includes a single terminal link stimulus. Two models, the temporal information account (Cunningham and Shahan, J Exp Psychol Anim Learn Cogn 44:1-22, 2018) and the ∆-∑ hypothesis (González et al., J Exp Anal Behav 113:591-608, 2020), presuppose that these procedures are equivalent, but no formal comparison is available. Here we test whether or not these procedures are functionally equivalent. One group of pigeons was trained with the standard procedure, another group with the original procedure, and a third group was trained with a hybrid of the other two (i.e., the two options were the optimal links of the standard and original procedures). Our findings indicate that the number of terminal link stimuli in the optimal option is inconsequential vis-à-vis choice. Moreover, our findings also indicate that latencies to respond are a sensitive metric of value and choice. As predicted by the Sequential Choice Model, we were able to predict simultaneous choices from the latencies of sequential choices and observed a substantial shortening of latencies during simultaneous choices.

Are divergence point analyses suitable for response time data?

Estimating the time course of the influence of different factors in human performance is one of the major topics of research in cognitive psychology/neuroscience. Over the past decades, researchers have proposed several methods to tackle this question using latency data. Here we examine a recently proposed procedure that employs survival analyses on latency data to provide precise estimates of the timing of the first discernible influence of a given factor (e.g., word frequency on lexical access) on performance (e.g., fixation durations or response times). A number of articles have used this method in recent years, and hence an exploration of its strengths and its potential weaknesses is in order. Unfortunately, our analysis revealed that the technique has conceptual flaws, and it might lead researchers into believing that they are obtaining a measurement of processing components when, in fact, they are obtaining an uninterpretable measurement.

TMS motor mapping in brain tumor patients: more robust maps with an increased resting motor threshold

OBJECTIVE

Navigated transcranial magnetic stimulation (nTMS) has found widespread usage across many clinical centers as part of their surgical planning routines. NTMS offers a non-invasive approach to delineation of the motor cortex, in which the region is outlined through electromagnetic stimulation and electromyographic recordings of target muscles. Several neurophysiological parameters such as the motor evoked potential (MEP) and its derivatives, the resting motor threshold (RMT) and motor latency, are collected. The present study investigates the clinical feasibility and reproducibility of increasing the MEP threshold in brain tumor patients, with the goal to improve the robustness of the procedure.

MATERIALS AND METHODS

Twenty-three subjects with peri-motor cortex tumors underwent motor mapping with nTMS. RMT was calculated with both conventional 50-μV and experimental 500-μV MEP amplitude thresholds. Motor mapping was performed with 105% of both RMTs stimulator intensity using the FDI as the target muscle.

RESULTS

Motor mapping was possible in 20 patients with both the conventional and experimental thresholds. No significant differences in area size were found between motor area maps generated with a conventional 50-μV threshold in comparison to those generated with the higher 500-μV threshold (50 μV 272.56 mm² [170.47-434.31] vs. 500 μV 240.54 mm² [169.77-362.84], P = 0.34). Latency time was significantly reduced in 500-μV recordings relative to 50-μV recordings (50 μV 23.38 ms [22.55-24.51] vs. 500 μV 22.57 ms [21.41-23.70], P < 0.001). Both electric field intensity (50 μV 63.81 V/m [54.26-76.11] vs. 500 μV 77.83 V/m [65.21-93.94], P < 0.001) and RMT (50 μV 33 MSO% [28-36] vs. 500 μV 39.5 MSO% [32-44], P < 0.001) were significantly greater with the higher 500-μV threshold.

CONCLUSIONS

Our study demonstrates the feasibility of increasing the MEP detection threshold to 500 μV in brain tumor patients for RMT determination and motor area mapping with nTMS.

Preservation of motor maps with increased motor evoked potential amplitude threshold in RMT determination

OBJECTIVE

Non-invasive pre-surgical mapping of eloquent brain areas with navigated transcranial magnetic stimulation (nTMS) is a useful technique linked to the improvement of surgical planning and patient outcomes. The stimulator output intensity and subsequent resting motor threshold determination (rMT) are based on the motor-evoked potential (MEP) elicited in the target muscle with an amplitude above a predetermined threshold of 50 μV. However, a subset of patients is unable to achieve complete relaxation in the target muscles, resulting in false positives that jeopardize mapping validity with conventional MEP determination protocols. Our aim is to explore the feasibility and reproducibility of a novel mapping approach that investigates how an increase of the MEP amplitude threshold to 300 and 500 μV affects subsequent motor maps.

MATERIALS AND METHODS

Seven healthy subjects underwent motor mapping with nTMS. RMT was calculated with the conventional methodology in conjunction with experimental 300- and 500-μV MEP amplitude thresholds. Motor mapping was performed with 105% of rMT stimulator intensity using the FDI as the target muscle.

RESULTS

Motor mapping was possible in all patients with both the conventional and experimental setups. Motor area maps with a conventional 50-μV threshold showed poor correlation with 300-μV (α = 0.446, p < 0.001) maps, but showed excellent consistency with 500-μV motor area maps (α = 0.974, p < 0.001). MEP latencies were significantly less variable (23 ms for 50 μV vs. 23.7 ms for 300 μV vs. 23.7 ms for 500 μV, p < 0.001). A slight but significant increase of the electric field (EF) value was found (EF: 60.8 V/m vs. 64.8 V/m vs. 66 V/m p < 0.001).

CONCLUSION

Our study demonstrates the feasibility of increasing the MEP detection threshold to 500 μV in rMT determination and motor area mapping with nTMS without losing precision.

Open parallel cooperative and competitive decision processes: a potential provenance for quantum probability decision models

In recent years quantum probability models have been used to explain many aspects of human decision making, and as such quantum models have been considered a viable alternative to Bayesian models based on classical probability. One criticism that is often leveled at both kinds of models is that they lack a clear interpretation in terms of psychological mechanisms. In this paper we discuss the mechanistic underpinnings of a quantum walk model of human decision making and response time. The quantum walk model is compared to standard sequential sampling models, and the architectural assumptions of both are considered. In particular, we show that the quantum model has a natural interpretation in terms of a cognitive architecture that is both massively parallel and involves both co-operative (excitatory) and competitive (inhibitory) interactions between units. Additionally, we introduce a family of models that includes aspects of the classical and quantum walk models.