Investigating the Diversity of Evolved Cognitive Models in Delayed Match to Sample Experiments

SPECS 2024The construction of programs to model cognitive behaviour can be semi-automated, using program synthesis techniques such as genetic programming. However, these techniques can produce many candidate solutions of good fitness making it difficult to find the important similarities and differences which can explain model behaviour and lead to theoretical insights. Here we show how the diversity of generated models can be assessed using the Silhouette Index measure of cluster quality; the quantitative measure helps guide theorists to important qualitative differences in the models. Such differences can help inspire novel cognitive theories.Peer reviewe

Computational scientific discovery in psychology

Scientific discovery is a driving force for progress, involving creative problem-solving processes to further our understanding of the world. Historically, the process of scientific discovery has been intensive and time-consuming; however, advances in computational power and algorithms have provided an efficient route to make new discoveries. Complex tools using artificial intelligence (AI) can efficiently analyse data as well as generate new hypotheses and theories. Along with AI becoming increasingly prevalent in our daily lives and the services we access, its application to different scientific domains is becoming more widespread. For example, AI has been used for early detection of medical conditions, identifying treatments and vaccines (e.g., against COVID-19), and predicting protein structure. The application of AI in psychological science has started to become popular. AI can assist in new discoveries both as a tool that allows more freedom to scientists to generate new theories, and by making creative discoveries autonomously. Conversely, psychological concepts such as heuristics have refined and improved artificial systems. With such powerful systems, however, there are key ethical and practical issues to consider. This review addresses the current and future directions of computational scientific discovery generally and its applications in psychological science more specifically

Genetic Programming for Developing Simple Cognitive Models

©2023 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Frequently in psychology, simple tasks that are designed to tap a particular feature of cognition are used without considering the other mechanisms that might be at play. For example, the delayed-match-to-sample (DMTS) task is often used to examine short-term memory; however, a number of cognitive mechanisms interact to produce the observed behaviour, such as decision-making and attention processes. As these simple tasks form the basis of more complex psychological experiments and theories, it is critical to understand what strategies might be producing the recorded behaviour. The current paper uses the GEMS methodology, a system that generates models of cognition using genetic programming, and applies it to differing DMTS experimental conditions. We investigate the strategies that participants might be using, while looking at similarities and differences in strategy depending on task variations; in this case, changes to the interval between study and recall affected the strategies used by the generated models

Heuristic Search of Heuristics

© 2023 The Author(s), under exclusive license to Springer Nature Switzerland AG. All rights are reserved by the Publisher. his is the accepted manuscript version of a conference paper which has been published in final form at https://doi.org/10.1007/978-3-031-47994-6How can we infer the strategies that human participants adopt to carry out a task? One possibility, which we present and discuss here, is to develop a large number of strategies that participants could have adopted, given a cognitive architecture and a set of possible operations. Subsequently, the (often many) strategies that best explain a dataset of interest are highlighted. To generate and select candidate strategies, we use genetic programming, a heuristic search method inspired by evolutionary principles. Specifically, combinations of cognitive operators are evolved and their performance compared against human participants’ performance on a specific task. We apply this methodology to a typical decision-making task, in which human participants were asked to select the brighter of two stimuli. We discover several understandable, psychologically-plausible strategies that offer explanations of participants’ performance. The strengths, applications and challenges of this methodology are discussed

Vegetation response to rapid climate change during the Lateglacial-Early Holocene transition at Gola di Lago, southern Switzerland

Predicting the effects of ongoing climate warming on vegetation requires a long-term perspective of past ecosystem dynamics. We therefore analysed the sedimentary record from the mire Gola di Lago (985 m a.s.l.) in southern Switzerland, to better understand the vegetation response to past rapid climate change. We present a high-resolution pollen and plant macrofossil study from the Lateglacial to the Early Holocene (13 400-10 400 cal. a BP), a climatic transition that represents a close analogue to current global warming. The vegetation responses during this time match previously analysed palaeoecological sites south of the Alps. At the end of the Bolling-Allerod interstadial, the site was surrounded by open larch forest. The beginning of the Younger Dryas was characterized by the local presence and rapid expansion of Pinus cembra, whereas the second part was dominated by Pinus sylvestris, Betula and Larix decidua. These vegetation dynamics agree well with independent climate data indicating a cold and dry start and a subsequent shift to slightly warmer climate. The following rapid temperature increase at the beginning of the Holocene resulted in an increase in forest density and the establishment of novel temperate vegetation assemblages, without major changes in species diversity. Noteworthy, during the Younger Dryas-Early Holocene transition, long-lived cold-adapted tree line species such as P. cembra and L. decidua persisted over several centuries, while open boreal forests dominated by P. sylvestris and Betula expanded, indicating high resilience to climatic changes. The results of Gola di Lago suggest that climate warming led to a significant change in vegetation communities through species range shifts. Our study also indicates that some species may potentially be able to locally persist under current global warming, forming novel vegetation assemblages with newly establishing species

Synthesising cognitive models with genetic programming

Developing, understanding and verifying the behaviour of cognitive models is a non-trivial task. A good cognitive model explains and predicts human behaviour in a particular experimental setting. Cognitive models are often in the form of computer programs which need to be designed and written for the given experiment and behaviour: time constraints or natural bias (oversights) often lead to models written by human programmers being constrained to particular theoretical assumptions. We apply program synthesis to this task, introducing novel training and post-processing techniques; our experiments automatically create good quality models, and help visualise the structure of the solution space.Peer reviewe

Evolving Understandable Cognitive Models

© 2022 The Author(s), published by the Applied Cognitive Science Lab, Penn State. This is the accepted manuscript version of a conference paper which has been published in final form at http://www.frankritter.com/papers/ICCM2022Proceedings.pdfCognitive models for explaining and predicting human performance in experimental settings are often challenging to develop and verify. We describe a process to automatically generate the programs for cognitive models from a user-supplied specification, using genetic programming (GP). We first construct a suitable fitness function, taking into account observed error and reaction times. Then we introduce post-processing techniques to transform the large number of candidate models produced by GP into a smaller set of models, whose diversity can be depicted graphically and can be individually studied through pseudo-code. These techniques are demonstrated on a typical neuro-scientific task, the Delayed Match to Sample Task, with the final set of symbolic models separated into two types, each employing a different attentional strategy

Palaeoecological multiproxy reconstruction captures long-term climatic and anthropogenic impacts on vegetation dynamics in the Rhaetian Alps

Alpine ecosystems are particularly affected by climate change due to their high sensitivity to temperature variations. Understanding the response of vegetation to rapid temperature increase and human impact is necessary to produce accurate and reliable predictions of future mountain vegetation and mitigate climate change impacts. Our multiproxy study reconstructs climate, fire, and vegetation dynamics over the last 14,200 cal. BP at Lai da Vons (1991 m a.s.l.), a subalpine lake situated in the treeline ecotone in Eastern Switzerland. Our results based on geochemical analysis (XRF), pollen and charcoal analysis, and high-resolution macrofossil analysis reveal that early afforestation started already at the onset of the Holocene, dominated by Pinus cembra and Larix decidua. Larch and stone pine formed closed forests at the site at 10,300 cal. BP. From 9500 cal. BP onwards, when summer temperatures were warmer than today, Picea abies expanded simultaneously with Abies alba. In the past 6500 years, increasing human impact, culminating during two main phases of landscape opening and intensification of fire regime, led to a progressive increase of species richness. Considering future climate change, an upward shift of treeline and timberline is expected in the absence of domesticated herbivores. We advocate that low-intensity pastoralism in such a cultural landscape is essential to preserve the plant diversity of species-rich mountain meadows

Prácticas participativas de salud mental en contexto de pandemia: apuntes sobre la experiencia de la Radio La Colifata desde la perspectiva de su coordinación

Este escrito forma parte de un proyecto de investigación UBACyT radicado en la Facultad de Psicología, UBA. Su objetivo es indagar en los procesos de transformación llevados adelante en prácticas participativas que articulan salud mental y comunicación en un Hospital monovalente de salud mental de la Ciudad de Buenos Aires durante la pandemia por COVID-19. Se trata de un estudio cualitativo, exploratorio y descriptivo que toma como objeto de indagación las prácticas desarrolladas por la Organización Civil La Colifata desde la perspectiva de sus actores. Se tomaron entrevistas en profundidad y se realizó un conversatorio con integrantes de los equipos de coordinación. El proceso de sistematización del material recogido utilizó técnicas de análisis de contenido. Como resultados se presenta una caracterización de la experiencia y las principales transformaciones en contexto de pandemia, incorporando obstáculos, aprendizajes y fortalezas. Se discute la dimensión vincular y su relación con la perspectiva de cuidados, así como lo significativo del sostenimiento de una dimensión deseante y creativa en la experiencia estudiada. Se concluye que dicha perspectiva vincular y el fortalecimiento de una red de cuidados significativa se han constituido en elementos clave para el sostenimiento de actividades en contexto de excepcionalidad

Control de portación de Streptococcus agalactiae, vaginosis e infección urinaria en embarazadas

La vaginosis bacteriana (Vb) es una infección endógena que se caracteriza por signos y síntomas producidos por el desequilibrio de la microbiota vaginal. Últimamente se la ha asociado con varios problemas graves de la salud reproductiva femenina como el incremento en las probabilidades de contraer una infección pélvica y con partos prematuros, recién nacidos con bajo peso, ruptura prematura de membranas, etc. La sepsis temprana por Streptococcus agalactiae es una enfermedad de alta mortalidad neonatal que puede prevenirse con el uso de penicilina intraparto. Por otra parte, el control de la portación de  infección urinaria (IU) y la bacteriuria asintomática (BA) puede tener un efecto significativo en la prevención de la morbilidad  materno-fetal. El objetivo de este trabajo fue detectar la presencia de S. agalactiae en hisopados vaginales y rectales de mujeres embarazadas, efectuar el diagnóstico de Vb y determinar la presencia de IU o BA en alguna etapa del embarazo. Se tomaron las muestras de exudados vaginales y de hisopado anal en embarazadas que se asisten en salas de atención primaria. Se realizaron las determinaciones correspondientes a los criterios de Nugent y Amsel para Vb y se sembraron en agar sangre de carnero y en caldo de enriquecimiento para S. agalactiae.Las muestras de orina se sembraron en agar CLDE y agar sangre ovina. Se jerarquizaron los microorganismos que se encontraban en recuentos > 105 ufc/ml en caso de no manifestar síntomas y en recuentos >103 ufc/ml en las mujeres sintomáticas. La siembra, aislamiento e identificación se realizaron por métodos convencionales. Se estudiaron 1052 pacientes. La portación de S. agalactiae se detectó en el 4.0% de las mujeres. Se halló Vb en el 18.9% de las embarazadas evaluadas y al 8.4% se les diagnosticó bacteriuria asintomática en distintas etapas del embarazo. No se evidenciaron casos de IU. La prevalencia de Vb resultó similar a lo mencionado en otros estudios argentinos pero la prevalencia de colonización con  S. agalactiae y de BA fue menor de lo esperable (aproximadamente 5-20% y 10% respectivamente). En todos los casos se tomaron las medidas preventivas adecuadas y se estableció una normativa de trabajo a seguir en el futuro.