80 research outputs found
LeDeepChef: Deep Reinforcement Learning Agent for Families of Text-Based Games
While Reinforcement Learning (RL) approaches lead to significant achievements
in a variety of areas in recent history, natural language tasks remained mostly
unaffected, due to the compositional and combinatorial nature that makes them
notoriously hard to optimize. With the emerging field of Text-Based Games
(TBGs), researchers try to bridge this gap. Inspired by the success of RL
algorithms on Atari games, the idea is to develop new methods in a restricted
game world and then gradually move to more complex environments. Previous work
in the area of TBGs has mainly focused on solving individual games. We,
however, consider the task of designing an agent that not just succeeds in a
single game, but performs well across a whole family of games, sharing the same
theme. In this work, we present our deep RL agent--LeDeepChef--that shows
generalization capabilities to never-before-seen games of the same family with
different environments and task descriptions. The agent participated in
Microsoft Research's "First TextWorld Problems: A Language and Reinforcement
Learning Challenge" and outperformed all but one competitor on the final test
set. The games from the challenge all share the same theme, namely cooking in a
modern house environment, but differ significantly in the arrangement of the
rooms, the presented objects, and the specific goal (recipe to cook). To build
an agent that achieves high scores across a whole family of games, we use an
actor-critic framework and prune the action-space by using ideas from
hierarchical reinforcement learning and a specialized module trained on a
recipe database
Language Models that Seek for Knowledge: Modular Search & Generation for Dialogue and Prompt Completion
Language models (LMs) have recently been shown to generate more factual
responses by employing modularity (Zhou et al., 2021) in combination with
retrieval (Adolphs et al., 2021). We extend the recent approach of Adolphs et
al. (2021) to include internet search as a module. Our SeeKeR (Search
engine->Knowledge->Response) method thus applies a single LM to three modular
tasks in succession: search, generating knowledge, and generating a final
response. We show that, when using SeeKeR as a dialogue model, it outperforms
the state-of-the-art model BlenderBot 2 (Chen et al., 2021) on open-domain
knowledge-grounded conversations for the same number of parameters, in terms of
consistency, knowledge and per-turn engagingness. SeeKeR applied to topical
prompt completions as a standard language model outperforms GPT2 (Radford et
al., 2019) and GPT3 (Brown et al., 2020) in terms of factuality and topicality,
despite GPT3 being a vastly larger model. Our code and models are made publicly
available
Facial emotion recognition in agenesis of the corpus callosum
Background: Impaired social functioning is a common symptom of individuals with developmental disruptions in callosal connectivity. Among these developmental conditions, agenesis of the corpus callosum provides the most extreme and clearly identifiable example of callosal disconnection. To date, deficits in nonliteral language comprehension, humor, theory of mind, and social reasoning have been documented in agenesis of the corpus callosum. Here, we examined a basic social ability as yet not investigated in this population: recognition of facial emotion and its association with social gaze. Methods: Nine individuals with callosal agenesis and nine matched controls completed four tasks involving emotional faces: emotion recognition from upright and inverted faces, gender recognition, and passive viewing. Eye-tracking data were collected concurrently on all four tasks and analyzed according to designated facial regions of interest. Results: Individuals with callosal agenesis exhibited impairments in recognizing emotions from upright faces, in particular lower accuracy for fear and anger, and these impairments were directly associated with diminished attention to the eye region. The callosal agenesis group exhibited greater consistency in emotion recognition across conditions (upright vs. inverted), with poorest performance for fear identification in both conditions. The callosal agenesis group also had atypical facial scanning (lower fractional dwell time in the eye region) during gender naming and passive viewing of faces, but they did not differ from controls on gender naming performance. The pattern of results did not differ when taking into account full-scale intelligence quotient or presence of autism spectrum symptoms. Conclusions: Agenesis of the corpus callosum results in a pattern of atypical facial scanning characterized by diminished attention to the eyes. This pattern suggests that reduced callosal connectivity may contribute to the development and maintenance of emotion processing deficits involving reduced attention to others' eyes
A category-specific response to animals in the right human amygdala
The amygdala is important in emotion, but it remains unknown whether it is specialized for certain stimulus categories. We analyzed responses recorded from 489 single neurons in the amygdalae of 41 neurosurgical patients and found a categorical selectivity for pictures of animals in the right amygdala. This selectivity appeared to be independent of emotional valence or arousal and may reflect the importance that animals held throughout our evolutionary past
From early markers to neuro-developmental mechanisms of autism
A fast growing field, the study of infants at risk because of having an older sibling with autism (i.e. infant sibs) aims to identify the earliest signs of this disorder, which would allow for earlier diagnosis and intervention. More importantly, we argue, these studies offer the opportunity to validate existing neuro-developmental models of autism against experimental evidence. Although autism is mainly seen as a disorder of social interaction and communication, emerging early markers do not exclusively reflect impairments of the “social brain”. Evidence for atypical development of sensory and attentional systems highlight the need to move away from localized deficits to models suggesting brain-wide involvement in autism pathology. We discuss the implications infant sibs findings have for future work into the biology of autism and the development of interventions
The role of the amygdala in face perception and evaluation
Faces are one of the most significant social stimuli and the processes underlying face perception are at the intersection of cognition, affect, and motivation. Vision scientists have had a tremendous success of mapping the regions for perceptual analysis of faces in posterior cortex. Based on evidence from (a) single unit recording studies in monkeys and humans; (b) human functional localizer studies; and (c) meta-analyses of neuroimaging studies, I argue that faces automatically evoke responses not only in these regions but also in the amygdala. I also argue that (a) a key property of faces represented in the amygdala is their typicality; and (b) one of the functions of the amygdala is to bias attention to atypical faces, which are associated with higher uncertainty. This framework is consistent with a number of other amygdala findings not involving faces, suggesting a general account for the role of the amygdala in perception
Overlapping phenotypes in autism spectrum disorder and developmental coordination disorder: A cross-syndrome comparison of motor and social skills
Motor and social difficulties are often found in children with an autism spectrum disorder (ASD) and with developmental coordination disorder (DCD), to varying degrees. This study investigated the extent of overlap of these problems in children aged 7-10 years who had a diagnosis of either ASD or DCD, compared to typically-developing controls. Children completed motor and face processing assessments. Parents completed questionnaires concerning their child’s early motor and current motor and social skills. There was considerable overlap between the ASD and DCD groups on the motor and social assessments, with both groups more impaired than controls. Furthermore, motor skill predicted social functioning for both groups. Future research should consider the relationships between core symptoms and their consequences in other domains
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