International Journal of
and Public Health
Exploring the Impact of Internet Use on Memory
and Attention Processes
Josh A. Firth 1,2 , John Torous 3and Joseph Firth 4,5 ,*
1Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX2 8QJ, UK;
2Merton College, University of Oxford, Oxford OX2 8QJ, UK
3Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School,
Boston, MA 02215, USA; firstname.lastname@example.org
4Division of Psychology and Mental Health, University of Manchester, Manchester M13 9PL, UK
5NICM Health Research Institute, Western Sydney University, Westmead, NSW 2145, Australia
Received: 5 November 2020; Accepted: 16 December 2020; Published: 17 December 2020
The rapid uptake of the internet has provided a new platform for people to engage with
almost all aspects of life. As such, it is currently crucial to investigate the relationship between
the internet and cognition across contexts and the underlying neurobiological mechanisms driving this.
We describe the current understanding of this relationship across the literature and outline the state
of knowledge surrounding the potential neurobiological drivers. Through focusing on two key areas
of the nascent but growing literature, ﬁrst the individual- and population-level implications for
attention processes and second the neurobiological drivers underpinning internet usage and memory,
we describe the implications of the internet for cognition, assess the potential mechanisms linking
brain structure to cognition, and elucidate how these inﬂuence behaviour. Finally, we identify areas
that now require investigation, including (i) the importance of the variation in individual levels of
internet usage, (ii) potential individual behavioural implications and emerging population-level
eﬀects, and the (iii) interplay between age and the internet–brain relationships across the stages
cognitive processes; digital health; digital technology; mHealth; neuroscience; social media
1. Understanding Internet–Brain Relations
In recent years, the internet has become an integral aspect of everyday life for most adults
and adolescents [
], producing a global shift in how people search for and share information, connect
with one another, obtain social recognition and rewards, and acknowledge social status. This has
become particularly pronounced with the rise of smartphone technologies, which oﬀer constant internet
access and encourage individuals to remain always connected to the online world.
Along with the vast range of possibilities of harnessing the internet for improving the self
and society, the potential risks of extensive internet usage are also becoming evident [
various lines of research have now begun to examine if, and how, this widespread and extensive
internet usage may adversely impact our cognitive processes and how changes in brain functioning
may underpin these eﬀects [
]. However, the majority of studies to date have only investigated
speciﬁc online activities in isolation, making it diﬃcult to draw overall conclusions. Nevertheless,
some attempts have recently been made to synthesize the broad literature surrounding this area [
and a framework of primary areas of cognitive functions (in relation to the internet) has been established
as including (i) social cognition, (ii) attentional processes, and (iii) memory storage/retrieval.
Int. J. Environ. Res. Public Health 2020,17, 9481; doi:10.3390/ijerph17249481 www.mdpi.com/journal/ijerph
Int. J. Environ. Res. Public Health 2020,17, 9481 2 of 12
While modern synthesis and reviews have summarised the previously available evidence for
the impact of the internet on cognition [
], further examination is still required to update and draw
further attention to more recent, emerging aspects of how internet usage can impact cognitive processes.
Indeed, while the relationship between the internet and social cognition is without a doubt an important
area (see Box 1), the processes of attention and memory are currently experiencing rapid growth in
terms of developing our understanding of how cognition is aﬀected by internet usage. Such growth is
particularly driven through research into these two cognitive processes providing new insights into
the speciﬁc implications of internet-related cognitive changes at the individual and population level
and the neurobiological mechanisms that underpin these apparent relationships.
Box 1. Social cognition.
Although not the primary focus of this review, the interplay between the internet and social cognition is
referred to across various contexts in this synthesis, as this area of research is a particularly rapidly developing
topic across ﬁelds and is allowing various powerful empirical studies due to the vast number of data available
within this area, particularly from harnessing social media. The current framework characterizes the overlap
between online social networks and real-world sociality as a “new playing ﬁeld for the same game” [
social-networking platforms on the internet clearly provide unparalleled potential for social interactions,
a substantial body of literature demonstrates that core socio-cognitive processes and social network structures
integral to “real-world sociality” are reﬂected in online social networks [
]. The strong correlations between
neural processes implicated in both online and oﬄine social interactions further illustrate how “artiﬁcial” aspects
of social media platforms (e.g., the quantitative metrics of popularity, such as likes of posted content and explicit
friendship requests/acceptance) can have “real-world” social consequences [
]. For instance, compelling
evidence has recently demonstrated that being subjected to online rejection evokes the same neural responses as
those seen in “real-world’ rejection [
] Thus, by presenting an artiﬁcial environment that so closely interacts
with regular sociality, online social networks have the potential to interfere with a broad range of cognitive
processes involved in social comparisons, self-evaluations, and even mental health [
]. Attempts to now
understand how the relationship between internet usage and social cognition may carry-over into aﬀecting other
cognitive processes (such as attention and memory as referred to across this review) will be of great use for
increasing knowledge on the cross-contextual implications of the internet.
First, for attention, the perpetual ﬂow of information provided by the internet may potentially
interfere with sustained concentration, by prompting people towards “media multi-tasking” between
diﬀerent types of incoming sources of information [
]. Indeed, the available data support the hypothesis
that engaging in excessive media multi-tasking reduces performance in sustained concentration
]. Additionally, recent experimental studies have found that even brief interaction with
hyperlinked websites can produce notable immediate reductions in concentration capacities; deﬁcits
that can persist for a short duration even after ceasing internet usage .
Secondly, memory is another cognitive process that may be impacted by the internet, due to
the persistent access to factual information aﬀorded by ubiquitous internet access. The internet may act
as a “superstimulus for transactive memory” [
] by tilting us towards an over-reliance on the online
world as an endless, and always available, source of external memory storage. Supporting this,
a number of empirical studies have found that using the internet for information-gathering tasks does
accelerate the process but appears to fail in recruiting certain patterns of brain activation important for
long-term storage of the retrieved information [25,26].
In this paper, we aim to further examine the mechanisms through which internet usage may
inﬂuence human cognition, particularly with regards to focusing on the recent ﬁndings around
the impact of internet usage on attention and memory, due to the rapid and constant growth of research
in these two areas. To do this, we build on the evidence presented in previous reviews [
] to ﬁrstly
utilise the evidence and literature surrounding the internet aﬀecting attentional capacities, primarily
through describing how extensive internet usage and the mass of information aﬀorded from this may
predispose us towards media-multitasking and divided attention, at the level of both the individual
and the population/society. Secondly, we use the recent ﬁndings from the emerging literature on
memory processes to examine the neurobiological mechanisms that may underlie internet-induced
Int. J. Environ. Res. Public Health 2020,17, 9481 3 of 12
alterations in memory, with particular emphasis on the important indication that these relationships
may vary across diﬀerent age groups. Third and ﬁnally, we highlight the promising topics within these
areas and how further investigation of these will beneﬁt the wider ﬁeld. Reviewing all evidence, we
oﬀer recommendations for how the potentially adverse eﬀects of internet usage could be ameliorated
or avoided using emerging evidence.
2. The Impact of Internet Use on Attention
The relationship between the internet and attention processes is experiencing relatively rapid
development; as such, it is particularly important that regular synthetic updates are considered.
Although there is clearly a broad array of processes through which the internet could impact core
cognitive processes (i.e., as outlined above), its inﬂuence on attention has recently provided an especially
rich knowledge base through which the digitalised world may have cognition-related implications
for the individual and also potential population-level eﬀects on attention changes. Interestingly,
at both of these levels (i.e., individual and population), there is an emerging, but largely independent,
demonstration that the actual extent of internet usage (rather than just access to it) is an important factor
for shaping cognition. In this context, we discuss the inﬂuence of internet usage for cognitive processes
in the individual and then consider how this also relates to population-level implications. In doing so,
we hope to emphasise that, while it may be particularly challenging to assess how individual-level
implications of internet usage may scale directly to shape societal level outcomes, it is becoming
apparent that attention processes may provide an in-road into investigating these phenomena.
2.1. Individual-Level Implications
While it is straightforward to conceptualise “internet usage” as a dichotomous variable or separate
individuals into users vs. non-users, the intricacies of internet usage diﬀer hugely between individuals.
First, the most strikingly variable that would be expected to moderate the eﬀects of internet usage on
the brain would be the quantity of use. Indeed, a large sum of research has investigated the correlates
of the highest levels of internet usage and dependence, speciﬁcally in those with “internet use
disorders” (IUDs). Indeed, a growing amount of research is beginning to advance the understanding
of the processes underpinning IUDs, the risk factors, and the potential treatments (as synthesised in
Figure 1), and, although not the primary topic of this review, this area now provides a speciﬁcally
useful and applied avenue for elucidating the consequences of the quantity of internet usage on
individual-level attention. For instance, a 2017 review [
] identiﬁed structural changes or deﬁcits in
brain regions associated with attentional control, reward processing and motivation in those with IUDs
compared to healthy controls. IUD-related deﬁcits in these brain regions associated with cognitive
control also appear to be reﬂected, or even manifest, in the heightened rates of related behavioural
deﬁcits associated with IUD. It would be particularly interesting to examine how quantity interacts
with quality/type of usage (e.g., social media usage vs. online gambling usage) and its impact on IUD.
With regards to eﬀects on attention/concentration, a vast sum of research has shown strong links
between excessive usage of the internet and IUDs (i.e., Figure 1), and this is now beginning to be linked
to attention-deﬁcit hyperactivity disorders. Most notably, a 2017 systematic review examined the link
between IUDs and ADHD across 15 independent studies (2 cohort studies and 13 cross-sectional
] and found that individuals with IUDs had over a 3 times higher likelihood of ADHD than
healthy controls. Even after adjusting for potentially confounding factors, the adjusted odds ratio for
ADHD in IUD individuals remained clinically and statistically signiﬁcant (OR =2.51, 95% C.I. =2.1 to
3.0). In further examinations of the data, the meta-analysis also found that IUDs are also associated
with more severe symptoms of ADHD, separately from the diagnosis of ADHD as a clinical condition.
For example, “inattention” scores were much higher in those with IUDs compared to control samples
(standardised mean diﬀerence of 0.84, 95% C.I. =0.65–1.02). Subsequently to the 2017 review, a more
recent cross-sectional study conﬁrmed the association between ADHD and IUDs in a sample of 1000
university students and professional online gamers .
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Synthesis of potential underpinning processes, risk factors, and treatments of internet
usage disorders, along with contemporary challenges faced by current research within this area.
The Targeted Treatments “CBT” box also includes internet-delivered cognitive behavioural therapy
(termed iCBT) .
Despite this strong observational link, the question of course remains whether excessive use
of the internet is a causal factor for ADHD, or whether adolescents with probable ADHD are more
susceptible to excessive internet usage. Future research, particularly research using methods that
allow investigation of the causality and direction of relationships, will provide much-needed insights
into the potential adverse impacts of the extensive internet usage on attentional disorders in young
]. However, due to the saturation of the internet across the globe, it is diﬃcult to
examine the causal relations between extensive internet usage. Nonetheless, a recent study by
Loh et al. [
] capitalised upon a rare sample of 35 young adults in India with minimal prior contact
with Internet-related technologies to experimentally investigate the impact of one month of unlimited
Internet access on neurocognition. Results showed that introducing high levels of internet usage to
this previously naïve sample increased media-multitasking behaviours in just one month, signiﬁcantly
more than a comparison group of internet-familiar young adults measured over the same timeframe.
Therefore, the individual-level attention eﬀects of the internet are clearly providing a body of evidence
showing that consideration of the quantity of usage is vital for understanding these relationships as
well as having applied implications in terms of psychological syndromes (here ADHD). Continued
research within this area, as well as further studies examining the context and quality of usage, is now
necessary to advance general understanding of these concepts.
2.2. Emerging Population-Level Eﬀects
Modiﬁcations to individual-level behaviour (often through cognitive changes) can ultimately
carry over to shape the emergent population-level processes that arise as a product of the actions of
the individuals within the society. As such, it is perhaps intuitive (but nevertheless of much importance)
that the possible eﬀects of the internet on divided attention appear to extend beyond considering
individuals that are vulnerable to developing speciﬁc attentional disorders and appear to also apply
on a population scale. However, combining a ﬁne-scale assessment of internet-related cognitive
changes at the individual-level with the large-scale examination of the consequences of such changes
Int. J. Environ. Res. Public Health 2020,17, 9481 5 of 12
for the population is particularly challenging, which means that, currently, such “holistic” empirical
studies are limited. Nevertheless, one of the most compelling pieces of evidence for this is provided
by a recent study examining the eﬀects of the internet on “collective attention span”. referring to
the amount of attention a popular topic receives on a population level [
]. Across various types of
online content, the study found strong evidence that, over time, shorter intervals of collective attention
are given to individual topics. For instance, the study ﬁrst examined 24 h usage of the top 50 most-used
Twitter hashtags across the world (sampled across 43 billion tweets), and how this changed over time.
Results showed that whereas a highly popular hashtag stayed within the top 50 for 17.5 h in 2013,
this gradually decreased over time, with top 50 hashtags maintaining their position for only 11.9 h by
2016. These patterns persisted across a range of online and oﬄine topics of public interest and across
diﬀerent timeframes .
On a further note, this study [
] provides a clear demonstration that the internet is not only
providing pathways for modifying population-level cognition but also enables the almost-real-time
quantiﬁcation of such phenomena. Therefore, although it is often problematic to infer causative
eﬀects from population-level observations, such large-scale and detailed data enables inferences
of population-level eﬀects that would otherwise be diﬃcult to quantitively identify. Indeed, this
study also employs a simple mathematical model to illustrate a basic mechanistic process of how
increased production and subsequent consumption of information cause population-level attention
span (and topic turnover rates) to shorten. Importantly, this mechanistic model explains the observed
data well, suggesting that the ever-faster ﬂows of collective attention were primarily driven by
the increasing ﬂow of information across the internet (i.e., total rates of internet-based informational
content production and consumption) and that the abundance of information available today is indeed
shortening the attention spans of the population. While further studies to determine the population-level
eﬀects of internet usage are needed, a fully detailed account of how these population-level consequences
arise also requires further understanding of individual-level eﬀects. Thus, empirical studies that
monitor individual cognitive changes in response to individuals’ internet usage, while simultaneously
measuring population-level outcomes, will provide new insights into how the eﬀects of sustained
internet usage on an individual level can manifest in changes in human cognition on a population-scale.
3. Neurobiological Underpinnings of Internet–Brain Relations
An emerging body of cross-sectional research indicates that certain aspects of internet usage
and online behaviours may be responsible for changes in brain structure and neural functioning,
independent of “oﬄine” versions of such behaviours. For instance, in the context of social cognition
(Box 1), neuroimaging studies have shown that individuals’ number of Facebook social connections
(their “Facebook friends”) can predict the grey matter volume of particular brain regions (such as
in the right entorhinal cortex [
]), while their real-world social networks (real-world friends)
holds little relationship with grey matter volume in these regions. Similarly, large amounts of
internet usage [
] and particularly media-multitasking [
] are correlated with reduced grey matter
volume in the anterior cingulate cortex and other prefrontal regions associated with sustaining
concentration/ignoring distractor stimuli [
]. However, these cross-sectional studies fail to
determine if these neurophysiological alterations are a cause or consequence of diﬀerent types of
internet usage and do not allow causal inferences. Indeed, it is currently almost impossible to establish
the long-term neural changes induced by engaging with the internet on a regular and sustained basis
due to the relatively recent adoption of the internet as the prime source of information consumption in
our society. Nonetheless, despite these challenges, memory processes are appearing to be proving
to be a particularly fruitful line of research, due to the vast amounts of knowledge surrounding
the fundamental neurological underpinnings of memory, as well as the ability to empirically test this
process within individuals .
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3.1. Internet Use and Memory Processes
Given the sheer amount of time the average individual spends engaging in online activities (of both
communicative and non-communicative nature), various insights into neurobiological pathways
through which online activities aﬀect cognition can be gained from investigating the shorter-term
eﬀects of internet usage on the brain [
]. Existing neuroimaging studies examining the acute
or short-term eﬀects of internet-based information processing/consumption currently report mixed
results. On one hand, an emergent body of literature indicates that the unprecedented potential for
ﬁnding additional (or alternative) information at the push of a button could interfere with the retention
of the information sought. To examine the neurobiological mechanisms through which this may
occur, experimental studies have compared internet searching to encyclopedia-based information
retrieval. These studies have found that internet searching can lead to reduced activation in brain
regions associated with working memory [
] and alterations in functional connectivity of memory
retrieval circuits [
]. Furthermore, large quantities of internet use are associated with a reduced
volume of the brain regions associated with cognitive control, hypothetically due to the internet
usage encouraging high levels of ﬂicking between information sources (i.e., media multitasking)
at the expense of brain circuitry used in sustained concentration [35,36].
Separately to media multitasking, another pathway through which online information sources
may interfere with regular memory processes is linked to the constant accessibility of this external
mass of information, which could potentially train a reliance towards informational retrieval over
informational retention [
]. Some studies have recently reported that internet search training may
increase behavioural impulses towards internet use by impacting upon brain regions involved in
reward, attention, and inhibitory control .
Furthermore, since the internet essentially acts as an external or transactive memory system, this
allows for “cognitive oﬀ-loading” of certain cognitively demanding tasks, such as semantic memory
]. This, in turn, may free up cognitive resources, which can instead then be reallocated
towards the use and development of higher-level cognitive abilities [
]. In line with this, internet
search training has recently been shown to facilitate neural connectivity by increasing white matter
3.2. Age Interactions in Internet–Brain Relations
Alongside examining the biological mechanisms that potentially govern the eﬀect of the internet on
the brain, there is an increasing indication that consideration must be given to how the eﬀects of internet
usage may diﬀer across age groups. For instance, cross-sectional studies in older adults have shown
that those who engage in more internet/email activity have greater performance in memory recall [
This positive eﬀect is possibly due to the cognitive stimulation from the wealth of information provided
by internet usage, facilitating the retention of cognitive capacities in ageing. As such, research reporting
that the reward, attention, and inhibitory control regions of the brain are negatively inﬂuenced by
internet search training (which holds consequences of internet-usage behavioural impulses) may not
be entirely generalizable, as these studies did not involve older individuals [
]. Neuroimaging studies
conducted in older adults who use the internet regularly show that internet-based information retrieval
uses greater amounts of neural circuitry than text-based information, speciﬁcally in regions implicated
in multiple higher-level cognitive functions, including decision making and complex reasoning [
However, there is a paucity of observational or experimental studies examining how long-term
internet use could produce sustained changes in brain development, connectivity, and structure,
and how this may underlie internet-induced alternations in typical cognitive processes. Of note,
there is a particular dearth of research in children and adolescents, whose younger brains may be
more responsive to the potential neuroplastic (i.e., ﬂexible neurological dynamics) changes associated
with increased internet use. To our knowledge, only one existing prospective study has examined
the associations between internet usage and brain development in youth. Speciﬁcally, the study
compared brain development over a three-year time period in children with frequent internet use vs.
Int. J. Environ. Res. Public Health 2020,17, 9481 7 of 12
children with low/no internet use [
]. The results suggest impeded development of verbal intelligence
in the young people who engaged in the highest levels of internet use over the three years. Furthermore,
the neuroimaging aspect of the study indicated a feasible neurobiological mechanism through which
this may occur, as higher frequency of internet use was linked to a reduction in the ageing-related
increases in both gray and white matter volume, brain regions which are linked with the development
of executive functions, language, and attentional control .
4. “What Now?” Research Priorities for Future Investigations
The latest synthesis (Parts 2 and 3 above) of the current research examining how the internet
may inﬂuence cognitive processes (particularly attention and memory) also provides insight into
the topics that currently hold unrecognized potential for furthering our understanding of how cognitive
processes are shaped by internet usage. Here, we outline how prioritizing further work in the areas
of establishing the long-term implications for cognitive processes, and understanding the context of
internet use. We conclude by looking beyond the primary risks of internet usage for cognition towards
discussing the positive implications the internet can hold for cognitive functioning.
4.1. Examining Long-Term Impacts of Internet Use
Currently, the ﬁndings of studies examining the acute eﬀects of internet usage are mixed, perhaps
due to the wide variety of diﬀerent online behaviours studied to date. Within the existing literature, there
is increasing evidence to indicate that using the internet extensively for factual information retrieval
and media-multitasking may impact adversely on brain regions associated with memory (i.e., through
long-term storage) and attention (i.e., through sustained concentration). However, the long-term eﬀects
of the internet on brain structure, and how this underpins downstream eﬀects on cognitive capacities,
remain unknown. In particular, future studies aiming to elucidate the neurobiological pathways
through which internet usage impacts cognition, including memory and attention, must also consider
the potential interaction of these eﬀects with age. Speciﬁcally, it should be considered that whereas
internet usage may facilitate cognitive stimulation in older people, it could also adversely impact
the development of higher-level cognitive capacities in youth. Alongside this, further consideration
must be aﬀorded to how various types of internet usage (i.e., diﬀerent online behaviours and styles of
using the internet) may ultimately determine the outcomes of internet usage for individuals.
4.2. Putting Cognitive Eﬀects of Internet Use in Context
While much research is being pursued in understanding how the quantity of internet usage may
inﬂuence cognitive processes, a less-frequently addressed question is, “what types of internet usage
aﬀect cognition, and in what ways?”
As outlined above, the two primary contexts of internet usage are information consumption
and social communication/interactions. Importantly, diﬀerentiating these two outlets may be crucial for
furthering our understanding, particularly as social usage of the internet is known to have a range of
distinct eﬀects. For instance, a major draw to the internet for some is to engage in virtual communities
in order to exchange information, social support, and friendship [
]. A further draw is the ability to be
able to express thoughts and feelings to large audiences via these communities, social networks, online
groups, or bulletin board systems. As such, the relevance, and the strength, of the relationship between
online social activity and that of the real world (see Box 1), along with the potential consequences of
this, is widely recognized as a topic of great interest [51,52]. There is also some indication that online
social interaction inﬂuences human cognition in ways analogous to real-world socialization (e.g., see
Box 1) and that brain regions linked to social cognition and associative memory are also correlated
with online social network size [
]. Indeed, memory capacity may act as a key determinant of online
social networks due to the large number of potential associates an individual may hold [
cross-sectional studies have shown excessive social media use to be associated with decreased grey
matter volume in regions related to emotional regulation and social cognition, including the bilateral
Int. J. Environ. Res. Public Health 2020,17, 9481 8 of 12
amygdala and right ventral striatu [
]. High daily Facebook use has also been linked with reduced
nucleus accumbens grey matter volume, a structure associated with motivation, reward, learning,
and addiction .
Clearly, commercial online social media platforms such as Facebook, Instagram, and Snapchat
have a remarkable capacity to engage users [
], and the exceptional aspects of internet-based
social networks bring into question whether the distinctive properties of the online world will hold
negative or positive ramiﬁcations for users’ well-being. As it stands, it is currently unknown if
and when engaging in online social networks is overall of beneﬁt or risk to general mental health.
On the one hand, increasing the potential for social interaction and expression appears to be beneﬁcial.
On the other hand, extensive usage may divert time away from “real-world” social interaction time
(see Box 1) and other beneﬁcial lifestyle behaviours such as physical activity and sleep [
examination of the costs and beneﬁts of internet usage in this context is now needed. To ameliorate
any adverse eﬀects of internet usage on brain functioning and mental health, there is a need for more
ﬁne-grained research to be conducted using real-time monitoring to establish what types/amounts
of internet usage may be detrimental to well-being, along with determining if and how potential
adverse may be mediated through other factors (e.g., through excessive internet usage being tied to
victimization, social withdrawal, or excessive sedentary behaviour). Following the acquisition of such
informative data, national and international health organizations could formulate evidence-based
guidelines on types and amounts of internet usage (for diﬀerent age groups) in a similar way to public
health guidelines for other health behaviours, e.g., physical activity and sleep [
]. These could then
be disseminated across the population such that the public can make informed decisions regarding
engaging in this relatively new facet of our lifestyles in an informed and safe manner.
Alongside this, it is important to gain further understanding of how social and non-social
(e.g., information-gathering) processes inﬂuence cognitive processing diﬀerently. However, it should
be considered that these contexts are often non-independent in reality. This non-independence is
generated by any activity that links these contexts within individuals. For instance, individuals will
often socially share information that they initially accessed in a non-social context. Furthermore,
links between the social- and non-social aspects of the internet could be created through information
gained in a non-social context, subsequently shaping an individual’s social interactions (in terms
of how they interact, and how often they engage in interactions) or through social outlets (such as
social media sites) being used as sources of searching for information (instead of non-social searching
platforms). Therefore, exploring the non-independence and the interactions between these contexts,
and the consequences for cognition, is now of great interest.
4.3. Discovering Avenues for Beneﬁcial Eﬀects of Connected Technologies
The evidence reviewed here has largely concerned the unintentional psychological consequences of
internet use. Along with the ongoing eﬀorts to understand the impact of the internet on human thought
processing and social behaviours, there is also a rapidly growing body of work examining how we can
capitalize upon this in a positive way. The most longstanding example of this is internet-delivered
cognitive behavioural therapy (iCBT), which is delivered remotely via a computerized interface and has
been shown to reduce psychological symptoms of various disorders with similar eﬃcacy to face-to-face
]. Although completion and ongoing adherence to these initial internet interventions
eﬀorts have proven challenging in real-world settings, the dawn of smartphone technologies presents
a novel platform for constantly accessible, easily disseminated and user-friendly internet-based
psychological interventions [
]. Evidence from meta-analyses has already demonstrated some eﬃcacy
of smartphone-delivered therapies for reducing both depression and anxiety [
]. However, the extent
to which beneﬁts observed in these trials are due to active components of the therapies themselves,
as opposed to individuals connection with their smart devices and expectations for beneﬁt, has yet to
be fully determined .
Int. J. Environ. Res. Public Health 2020,17, 9481 9 of 12
5. Summary and Conclusions
In conclusion, the introduction of the internet has clearly impacted many diverse aspects of
society. We hope this review further contextualises the current ﬁndings linking the internet to the brain,
cognition, and behavioural outcomes, while also highlighting the key areas for further research
in an era of rapid digitalisation. Whereas the eﬀects of internet use on the brain are not yet fully
understood, there is convergent evidence from multiple ﬁelds that our extensive interactions with
this novel feature of society could inﬂuence our attention, memory, and other aspects of cognition.
Further longitudinal work is required, particularly in young people. Nonetheless, as we continue to
reﬁne our understanding of potential adverse consequences of internet usage, now is also the time
for examining how this revolutionary tool can be utilized to produce improvements in psychological
and cognitive health.
Writing—review and editing, J.F., J.A.F., and J.T. All authors have read and agreed to
the published version of the manuscript.
Funding: This research received no external funding.
J.A.F. was supported by a research fellowship from Merton College and BBSRC (BB/S009752/1)
and acknowledges funding from NERC (NE/S010335/1). J.F. is supported by a University of Manchester Presidential
Fellowship (P123958) and a UK Research and Innovation Future Leaders Fellowship (MR/T021780/1).
Conﬂicts of Interest:
J.F. has received consultancy fees from Parachute BH for a separate project. All other authors
declare no conﬂict of interest.
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