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The cartography of dreams: application of computational linguistics to the study of sleep conscious experiences
No full textThe study of dreams represents a crucial intersection between
philosophical, psychological, neuroscientific, and clinical
interests. Since dreams are subjective experiences spontaneously
generated by the brain when it is partially disconnected from the
external environment and thus is let free to operate in an
unconstrained manner, their study could reveal specific mental
processes that are different from those occurring during
wakefulness and might provide crucial insights into brain
functioning, both in physiological and pathological conditions.
Given the high cost of sleep and dream research in terms of
human effort and funding, open science and the building of large-
scale datasets and repositories will constitute a key for significant
advances in the field. At the same time, the analysis of large
datasets will require a methodological shift, from human-based
assessments to more automated approaches. For instance,
methods based on natural language processing (NLP) could
replace manual scales and rating approaches for the assessment of
dream content. Such a methodological shift could also have
positive consequences concerning the reproducibility and
reliability of scientific results.
Based on the above premises, we created Somnieve, a
multimodal, open-source database collecting dream reports along
with demographic information and psychometric, cognitive, and
electroencephalographic measures obtained from a representative
sample of the healthy Italian adult population. In particular,
participants were asked to wear an actigraph and to record a
report of their last dream experience each morning upon
awakening for 14 days. Moreover, they completed a battery of
questionnaires and cognitive tests. The database currently
includes 1324 dream reports obtained from 161 healthy adult
individuals (66M, 18-65y).
Beside presenting and describing the Somnieve database, this
Thesis work exploited the database to investigate the individual
determinants of physiological dream content and recall
frequency. We relied on computational linguistics to test whether it might be possible to implement computational linguistics based
tools to automatically and objectively code dream content and
verify the existence of generalizable semantic patterns in dream
narratives. Moreover, we evaluated the inter- and intra-individual
factors affecting dream recall frequency.
Present results highlight the potential benefits that large
multimodal databases like Somnieve could bring for the field of
dream research. It is our hope that this, and similar independent
efforts by other laboratories, will contribute to improve
reproducibility in dream research and identify the individual
determinants of dream content and recall frequency in
physiological conditions, as well as quantify their possible
pathological alterations
Algorithmic management and wellbeng at work
Full text linkThis thesis explores the relationship between Algorithmic Management
(AM) and employee well-being in standard work environments. AM,
which refers to the use of algorithms to assume managerial functions
traditionally handled by humans, is an emerging phenomenon that
promises efficiency and objectivity. However, its impact on well-being is
still under heated debate, particularly regarding when and why AM
leads to positive or negative well-being outcomes for employees.
This research seeks to address this debate by examining AM from
different perspectives. Specifically, a multi-paradigmatic approach is
employed to study when AM enhances or erodes engagement,
autonomy, and overall well-being, as well as why these outcomes occur.
Drawing on both positivist and interpretivist approaches, this thesis
integrates quantitative and qualitative methods to investigate the
mechanisms, boundary conditions, as well as sensemaking processes
that shape the AM-well-being relationship.
First, in line with a positivist perspective, we use quantitative surveys to
explore how AM relates to employee engagement, mediated by social
and economic exchanges. The findings of the first study suggest AM
shifts work interactions from social to economic, often correlating with
lower engagement. A close leader’s moderating role is highlighted,
showing that strong interpersonal relationships can buffer these
negative effects. The second study addresses job autonomy, revealing
that AM’s association with reduced autonomy is influenced by factors
like systemic justice and individual proactivity, with high justice and
proactivity mitigating the loss the job autonomy.
The final study adopts an interpretivist approach, using qualitative
methods to explore how employees make sense of and respond to AM
in environments marked by uncertainty and complexity. It shows that
employees actively reinterpret or resist AM’s influence on their well-
being and emphasizes employees’ political potential to reshape
workplace dynamics in an AM context.
The thesis concludes that AM poses challenges to employee well-being
in standard work settings, despite efficiency gains. To balance these
aspects, organizations should implement AM systems that prioritize
genuine interpersonal relationships, justice, and autonomy. This research provides a nuanced understanding of AM’s dual nature and practical insights for its ethical use at work
Brexit, Trade Disruptions, and Export Recommendations
No full textThis doctoral dissertation is structured into three chapters, each ad-
dressing aspects related to policy evaluation, with a focus on events car-
rying substantial implications for the economy and international trade.
These events include the Brexit referendum, trade disruptions, and the
development of export recommendations.
The Economic Cost of a Referendum. The Case of Brexit. This paper esti-
mates how GDP would have behaved in the United Kingdom after the
Brexit referendum in the absence of the mentioned poll using the Syn-
thetic Control Method. We contribute to the research on the effects of
Brexit by quantifying the macroeconomic cost of this referendum before
the actual Brexit has taken place. We find a large and significant negative
effect of the Brexit referendum on the GDP of UK. This loss is increasing
in time representing, in 2017 Q4, 1.71% of the observed GDP of UK.
Assessing the Heterogeneous Impact of Economy-Wide Shocks: A Machine
Learning Approach Applied to Colombian Firms. This paper investigates the
impact of COVID-19 on Colombian exports, revealing a substantial de-
cline in survival probabilities during 2020. On average, we find that the
COVID-19 shock decreased a firm’s probability of surviving in the export
market by about 20 percentage points in April 2020. Importantly, ex-
porters more integrated into Global Value Chains (GVCs) and importing
higher value emerged as pivotal in bolstering exporter resilience during
the crisis, emphasizing the need for policies supporting varied import
networks, as well as international trade facilitation. Methodologically,
this research innovates by utilizing causal Machine Learning (ML) tools
in scenarios where the pervasive nature of the shock hinders the identi-
fication of a control group unaffected by the shock, as well as the ex-ante
definition of the intensity of the shock’s exposure of each unit, making a
traditional control group identification unfeasible. This approach effec-
tively predicts firms’ trade and uses these predictions to reconstruct the
counterfactual distribution of firms’ trade under different scenarios and
to study treatment effect heterogeneity.
Exports’ Survival in New Markets: A firm-level export recommendation
model. This paper investigates the factors that better predict a firm’s
trade status of exporters after expanding to a new destination, specif-
ically whether they continue exporting after two years. Using Colom-
bian customs data, I show that market-level information is crucial for
understanding export survival rates, beyond traditional firm-level char-
acteristics like export experience. The paper introduces a novel Machine
Learning-based export market entry recommendation tool, designed at
the firm-product market level. While firms in the sample did not have
access to this tool, the analysis observes which firms chose new destina-
tions that align with the recommendations generated by the tool. Sim-
ulated back-testing indicates that firms selecting destinations consistent
with the tool’s guidance would have experienced a 5 percentage point
higher survival rate compared to those choosing other destinations. Ad-
ditionally, product growth would have been 34 percentage points higher
for products where at least one firm followed the tool’s suggested market
entry, compared to those that did not. The findings suggest that incom-
plete market insights may lead to sub-optimal export decisions and that
exporters incur temporary trade as a way of experimentation and to re-
solve incomplete market information
Circumventing Plague: The Spatial Experience of Women and Men during the Outbreak of 1630-31 Bologna
Full text linkThough managing early modern plague in northern
Italy necessitated regulations and restrictions of movement
in order to combat outbreaks, the factors resulting in
immobility at the same time created opportunities for
mobility. The ability to move and interact within the urban
environment was contingent on social factors such as age,
gender, class and occupational status and remained
essential in the shaping of the spatial experience. Moreover,
the ability to move across barriers, such as crossing the
threshold of the home, formulated possibilities for social
life to flourish during plague. This study investigates the
relationships between early modern people and places
during the period of plague in Bologna from 1630-31
through the lens of the new mobilities paradigm. This
model interrogates how places are continuously shaped
and reshaped by way of human and non-human
interaction. Adopting approaches emerging from the
mobility turn, this research places emphasis on the social
drivers that contributed to movement and asks: how did
mobility inform the various experiences of the plague of
1630-31 in Bologna? Building on the extensive studies on
seventeenth-century plague for the cities of Milan, Venice
and Florence, this study offers new insights into the early
modern experience and approaches to plague from the
perspective of the significant northern Italian centre of
Bologna. This study draws on a broad array of primary
documents including handwritten and printed records,
encompassing contemporary chronicles, manuscripts and egal decrees. Historical sources including plague tracts
reveal contemporary understanding of combatting plague.
Visual sources, such as early modern paintings and
architectural plans, alongside digital maps of Bologna’s
network of plague hospitals, similarly play a crucial role in
uncovering the spatial experience during plague.
The research presented in this study contends that
the urban experience and the public health management of
early modern plague was informed by mobility.
Architecture, in combination with regulations and
disciplinary punishment, were used to contain, control and
limit the movement of people. Despite immobility, men and
women found ways to circumvent restrictions. They
crossed architectural divides by way of health passes or
illicit activities and traversed physical but also social
boundaries through professional opportunities. Bolognese
citizens continued to move by way of engaging with
devotional performances, such as processions. Ritualised
performance was enacted to counteract the moral causes of
the illness and ultimately served the social life of the
community. Mobility was also considered an asset for
plague management according to seventeenth-century
practice as demonstrated in the creation and employment
of a network of plague hospitals in Bologna. Moreover, this
study reveals how social dimensions contributed to varying
degrees of mobility as women, men, the nobility and the
poor each had diverse experiences of plague
Perception, Cognition and Ayahuasca A Multidimensional Analysis of Alter States of Consciousness
No full textMy Ph.D. thesis comprises a series of experiments aimed at
investigating the impact of a novel ayahuasca analog, pharmahuasca
(PHA), on face perception and creative cognition. These studies were
executed with a within-subject, double-blind, placebo-controlled
design involving 30 healthy male participants. Chapter 2 centers on
the effects of psychedelics on face perception, utilizing
electroencephalography (EEG) during a visual oddball task with self,
familiar, and unknown faces as stimuli. Notable changes induced by
PHA in early visual processing, such as increased P1 and reduced
N170 across all face categories, were observed. In late visual
processing, a decrease in neural activation in response to the self-face,
as indicated by the P300 wave, highlights the significance of
psychedelics in altering self-referential information processing.
Additionally, the impact of psychedelics on face discrimination was
explored through a two-alternative forced choice (2-AFC) task, where
faces are incrementally morphed to each other, revealing a decreased
sensitivity for discrimination during psychedelic experiences across
all face categories. Chapter 3 shifts focus to understanding how
psychedelics influence creative cognition. Through task-based
methodologies, the findings unveil a reduction in convergent
thinking without affecting on divergent thinking. Next, we
investigate how utilization of different thinking modes during the
artistic creation, specifically in the domain of painting, under the
influence of psychedelics. Importantly, there was a significant
reduction in transitions between different creative thinking modes
during the psychedelic-induced creative process, particularly
affecting stages traditionally requiring convergent thinking, offered
valuable insights into the phenomenological nuances of the interplay
between psychedelics and the dynamics of creative thinking
Phase Field methods for Fracture Mechanics in coupled problems
Full text linkNowadays, cutting-edge industry processes cannot thrive with-
out the integration of multidisciplinary perspectives in all its
associated processes. Even the field of Mechanics is not ex-
empt from such approaches, since most recent studies now
incorporate considerations spanning multiple size scales (multi-
scale) and encompassing various branches such as Chemistry,
Biology, Electricity, and Magnetism, among others (multi-physics).
This is what constitutes the very essence of a coupled prob-
lem in Mechanics. The principal objective of this thesis is to
specifically explore their impact on structural integrity and
reliability in the field of Fracture Mechanics. Consequently,
it is necessary to establish a robust mathematical framework
to assess the mechanical behavior and failure strength, con-
sidering the intricate influence of the multi-scale and multi-
physics fields associated with each problem. To accomplish
this mission, we have primarily utilized the phase-field ap-
proach for fracture, alongside the continuum damage me-
chanics technique.
Our efforts have been devoted to shed light on representative
coupled problems in Fracture Mechanics. To exemplify the
breadth of this field, our research comprises a diverse spec-
trum of topics. First, the research deals on the problem of hy-
drogen embrittlement in polycrystalline materials. Moreover,
the residual stress influence on the integrity of soft cylindrical
tubes has been investigated. Furthermore, a computational
framework for incompressible materials has been proposed.
The final topic concerns the application of this last formula-
tion in the simulation of swelling of thermoresponsive hydro-
gels
The Problem of Reverse Inference: Philosophical Models and Neuroscientifc Methods
No full textReverse inference is a crucial inferential strategy employed
by neuroscientists to infer the engagement of a cognitive pro-
cess from observed brain activation in functional magnetic
resonance imaging studies. Despite its widespread use, in
recent years reverse inference faced increasing skepticism, par-
ticularly after Russell Poldrack authoritatively criticized its
uncontrolled use in his influential 2006 paper.
The general aim of the thesis is to provide an assessment of the
current debate about reverse inference at the interface between
neuroscience and the philosophy of science, by evaluating the
models and methods proposed to improve the theory and
practice of reverse inference. To do this, I offer three main
contributions to the debate.
In the first part of the thesis, I offer a comprehensive and
updated overview of the problem of reverse inference in cur-
rent cognitive neuroscience, emphasizing both technical and
methodological issues.
In the second part, I present and discuss the different philo-
sophical models of reverse inference proposed in the literature,
assessing their relative advantages and limitations. I also dis-
cuss two novel models of reverse inference, one based on
Bayesian confirmation theory and one based on the idea of
inference to the best explanation.
In the third part, I present the main results of a systematic
review of the literature, aiming at evaluating the impact of
NeuroSynth, the most widely employed meta-analytical soft-
ware for performing reverse inference, on current practice in
neuroscientific research
Power, Legitimacy, and their Rituals and Imagery: Early Medieval Southern Italy in a cross-cultural Mediterranean Perspective
Full text linkAt the end of the X century, in the city of Benevento
appeared a liturgical medium that would soon become a
peculiarity of the religious life of Southern Italy for the
centuries to come: the illustrated scroll, containing the texts
of the so-called Exultet prayer and the blessing of the
Paschal candle, a ceremony to be held in the Easter Vigil.
The liturgy underlining such a ceremony in Southern Italy
changed over time, in particular when the original so-called
Beneventan liturgy (the traditional rite originating in the
city of Benevento after the arrival of the Lombards, as an
evolution of the more ancient Ambrosian liturgy) gave way
to the imposition of the Franco-Roman one, a result of the
spread of the reformist movement that characterized the
life of the Church during the XI century. Notwithstanding
these changes, the illuminated scroll kept its role and
importance, evolving and adapting itself to the new
circumstances until at least the XIII century.
Religious changes, however, did not come alone: during
the whole period from the X to the XII century, Southern
Italy as a whole underwent some drastic changes in its
political setting. From the second half of the IX century,
and precisely from 849, the year of the peace treaty that
marked the end of a long civil war, the old duchy of
Benevento (a principality since 774, when Arichis II started
styling himself as princeps) was divided into two distinct
entities: the principality of Benevento, and that of Salerno.
Later on, the latter lost its northernmost part, which became an independent county centred around the town of
Capua, whose rulers subsequently managed to reunite with
Benevento and, under Pandulf Ironhead (943-981) even
Salerno, in 978. The (temporary) reunification of the three
principalities in one single polity would mark the last
moment of unity for the Lombard people before the advent
of new political actors, who would radically change the
landscape of Southern Italy: the Normans.
This is not the place for a detailed narrative of the Norman
conquest of Southern Italy, and of the following birth of a
unified Regnum under Roger II in 1130. What is important
to note here is that the anarchic situation that reigned in
continental Southern Italy between the second half of the XI
century and the beginning of the XII, and then the birth of a
strong monarchy immediately after, both influenced
developments in the liturgical sphere and in the
organization of the Church. Moreover, Roger II’s new
political construction brought under a single rule the four
different, often conflicting, cultural worlds that for
centuries had interacted with each other in the southern
Italian arena: the Lombard, Frankish, Byzantine, and Arab
worlds.
Alongside the three Lombard principalities, indeed,
Southern Italy always saw the presence of lands under
Byzantine rule: at the beginning limited, after the first
Lombard invasion of the VI century, to the southernmost
part of modern day Puglia and to Calabria, the Eastern
Roman Empire managed to strengthen its presence and
recover some of the lost territories between the IX and X century, and again at the beginning of the XI century,
restoring its rule over much Apulia, Lucania, Calabria, and
even (briefly) in the very core of the Lombard
principalities, Benevento itself.1 On the Tyrrhenian coast,
also, a number of cities thrived as political entities
nominally still subject to the emperors in Constantinople,
but de facto increasingly independent: Naples, Amalfi,
Gaeta, among them. A more in-depth look at the political
developments that took place in Southern Italy during the
period under consideration here will be given in the course
of Chapter 2 (and, for what concerns the Byzantine
presence, in the Conclusions as well).
What is to be said now is that this peculiar political and
cultural landscape, as it took its shape from the VIII century
onwards, also resulted in the birth of a civilization with
characteristics and peculiarities of its own; a civilization that found its expression in the development of an artistic
language that ranged from the first exemplars of Lombard
‘royal’ architecture (such as the palatine church of S. Sofia
in Benevento, or the reconstruction of Salerno as a new
princely capital undertaken by Arichis II), to the most
remarkable forms of Romanesque art that developed under
the patronage of the first Norman rulers. During all this
time, the Exultet rolls stood firmly in their place, were kept
in use, and evolved in both iconography and text. As a
result, we currently see Exultet rolls spread from Pisa (two
at the Museo Diocesano, and one at the archive of the
Capitolo metropolitano, dating from the XI to the XIII
century), to Velletri, Salerno, Troia, Bari, Gaeta, Paris,
London, for a total of twenty-eight scrolls. A rich, though
not homogeneous, corpus, with differences in both original
composition (some, such as the Exultet from Avezzano,
were made without images) and state of preservation.
But to consider the scrolls as purely an expression of
religion or liturgy would be a mistake: both the chant and
its iconography, once this was introduced, contained clear
references to the secular authorities in the form of a
commemoration, made at the end of the prayer. As a result,
starting with the very first scroll in our possession, the Vat.
lat. 9820, most of the surviving exemplars show us
representations of the ruler (or rulers), representations that
changed over time and that represent, by themselves,valuable sources of information about the evolution in the
iconography of power in medieval Southern Italy.
Efficient and Accurate Analysis of Two Classes of Transparent Generative Models
Full text linkWhile widely used, generative models pose the challenging
task of deriving and analyzing their underlying distribution.
In this thesis, we focus on two classes of transparent genera-
tive models and present new methods to tackle this task.
Markov Population Processes use Continuous Time Markov
Chains to describe the evolution of populations over time.
Their analysis is often hindered by state-space explosion, tack-
led with deterministic approximation or truncation techniques.
We propose a method, Dynamic Boundary Projection, that
couples an exact stochastic description of a subset of states
and a deterministic approximation that dynamically shifts the
subset across the state space. The resulting finite set of ODEs
is asymptotically exact. We show that our method performs
well in terms of accuracy and runtimes on challenging sys-
tems. We also propose an extension that further reduces the
number of equations while maintaining good accuracy.
Probabilistic Programs leverage the power of programming
languages to define probabilistic models; however, no one-
fit-for-all solution exists to derive the posterior distribution.
We define a family of approximating semantics, Gaussian Se-
mantics, that leverages moment-matching and the approxi-
mation power of Gaussian Mixtures to approximate the joint
probability distribution over program variables. As the num-
ber of the moments matched increases, Gaussian Semantics
tends to the exact semantics. We implement an instance of
Gaussian Semantics that matches the first two order moments
and show that our implementation performs competitively
with respect to other state-of-the-art inference methods and
excellently on two classes of models taken from the literature
The Representation of Visual Naturalistic Stimuli in Resting State Activity: An Investigation in the Visual and Motor Areas Representations at Rest
Full text linkResting state is characterized as an offline period, during which the
eyes may be either open or closed. In this disengaged state, one’s
system operates independently of external input or feedback, and by
definition, relies on an internalized model of the world. Literature
shows that resting state activity may reflect the statistics of the natural
environment, but also the unique individual biases, and is possible to
be reshaped over time. This is highlighted by studies that show that
resting state fluctuations maintain traces of everyday activity; but how
are these representations extracted, how stable are they, and to what
extent are they malleable? To answer that we need to understand: 1)
How is our system structured to maintain regularities? 2) How are they
integrated in an internalized model? 3) How do low frequencies
fluctuate when detecting an error? The main aim of this thesis is to
understand how natural information is represented in resting state. The
working model is that (1) naturalistic information is processed along a
hierarchy in time and space to code higher level information that is low
dimensional and sparse (chapter 2). 2) This information is then
maintained in resting state in a generic form (chapter 3). 3) This is
achieved because low frequency fluctuations are adapted to naturalistic
statics, and hence are altered in otherwise unexpected situations
(chapter 4). We examined the functional connectivity (FC) of MEG
signal changes in the visual (VIS) and dorsal attention (DAN) networks
during the observation of naturalistic videos, by comparing them to a
pretrained convolutional network. We reveal distinct temporal
dynamics in processing low and high-level features. Low-level features
are immediately and abundantly represented, while high-level features
exhibit a delayed and scarce representation, potentially storing
information in a generic form (chapter 2). For instance, we find that the
BOLD multivoxel spatial representation of a still hand, controlled for
low-level features, is coherent with the spatial representation of the
resting somatomotor area, as opposed to another object such as a food
item (chapter 3). We suggest that the representations during resting
states may contribute to the goal of interacting with the environment.
This is enriched by our final findings; the multivoxel spatial
representation of observing common movements aligns more
coherently with resting somatomotor patterns as opposed to
uncommon (chapter 4)