11: Memory Topics

Neurological Mind Reading #

Team of neuroscientists at Carnegie Mellon led by Marcel Just are learning to read people’s minds based on fMRI cortical activation patterns

  • In early study, researchers were able to identify which of 10 similar objects (e.g., hammer vs. drill vs. screwdriver) people were viewing based on scans (Shinkareva, Mason, Malave et al., 2008)
  • Lab has now also identified activation patterns associated with (Wang, Cherkassky, & Just, 2017)
    • Different abstract ideas (e.g., forgiveness vs. gossip vs. spirituality)
    • Thinking in different languages
    • Different emotions
      • Participant is asked to think of scenario that would conjure up disgust, envy, etc. (e.g., someone vomiting at baseball game, beautiful model)
      • Computer is able to identify the emotion

  • fMRI cortical activation patterns can now also be used to distinguish between participants with autism and controls with 97% accuracy (Just, Cherkassky, Buchweitz et al., 2014)
    • When those with autism were asked to think of social interactions like adore, hug, humiliate, they showed significantly less activation in areas associated with the self than controls
      • Thought of words more like definitions, rather than experiences
  • Patients with suicidal ideation were asked to think about death related words (e.g., funeral, death) and positive words (e.g., praise, good, carefree)
    • Compared with non-suicidal controls, self-related brain regions showed significantly more activation for death-related words and less activation for positive words (Just, Pan, Cherkassky et al., 2017)

The Online Brain: Effects of the Internet on Cognition #

  • 45% of US teens report that they are online “almost constantly” (Pew Research Center, 2018)
  • According to review article published in World Psychiatry, research suggests that this increase in Internet use may be… (Firth, Torous, Stubbs et al., 2019)
    • Impairing our ability to sustain attention
    • Negatively impacting our memory and analytical thinking ability
    • Promoting a type of social comparison that increases risk of depression and mental health problems, especially among adolescents
      • Due to constant social comparison

Attention and impulse control #

  • Studies have shown that adopting a less physically and cognitively active lifestyle across the lifespan may accelerate loss of cognitive function
    • Similar to Alzheimer’s prevention
  • Emerging evidence indicates that disengaging from the “real world” in favor of virtual settings may similarly induce adverse neurocognitive changes
    • Ex: Adult participants (both gamers and non-gamers) engaged in an online role playing game daily for 6 weeks (55 hours total on average)
    • Showed significant reductions in gray matter within the orbitofrontal cortex relative to matched controls (Zhou, Montag, Sariyska et al., 2019)
      • The OFC is a brain region important in executive function, impulse control, and decision making
  • In addition, leading technology companies have been accused of intentionally capitalizing on the addictive potential of the Internet without concern for user well-being
    • They study, test, and refine attention-grabbing aspects of their websites and apps to promote extremely high levels of use

  • Tech companies try to maximize the amount of time you spend on your phone/computer because that is how they make their money
    • You don’t pay for Facebook; ads do
    • The more time you spend on Facebook, the more money they make from ads
      • Ad spending on social media has reached 40 billion dollars a year
  • So… computer scientists study huge data sets extensively to figure out how to get you to spend more time online
    • Example:
      • Holding some “likes” back for you to give you big burst later at exactly the right moment (based on complex algorithmic analyses) to effect “improvement in behavior”
      • Similar to gambling – you never know which roll (picking up the phone) will result in a rush, so you do it often
  • The typical person checks their phone every 15 minutes, and half the time there is no sort of alert… because checking the phone results in
    • Release of dopamine (associated with pleasure and “rewards”)
    • Reduction in cortisol (anxiety from not having checked phone in a while results in increased cortisol)
    • In addition, the intermittent reinforcement (which is what makes gambling so addictive) inherent to device-checking further perpetuates these compulsive behaviors

  • Cognitive consequences of the attention-grabbing Internet
    • As early as 2012, researchers found that 85% of teachers endorsed the statement that “today’s digital technologies are creating an easily distracted generation” (Pew Research Center, 2012)
  • Study of individuals who engaged in “heavy” (i.e., frequent and extensive) media multi-tasking compared to those who did not
    • Cognitive testing of the two groups found that, surprisingly, those involved in heavy media multi-tasking performed worse in task-switching tests than their counterparts
    • Closer inspection of data indicated that this was due increased susceptibility to distraction from irrelevant environmental stimuli (Ophir, Nass, & Wagner, 2009)
  • Though some studies have failed to find adverse effects of internet use on attention, overall, the literature does seem to indicate that those who engage in frequent and extensive media multi-tasking perform worse in various cognitive tasks, particularly for sustained attention (Uncapher & Wagner, 2018)
  • Lastly, the first longitudinal study (3-6 months) of media multi-tasking in young people found that frequent multi-tasking behaviors
    • Predicted the development of attentional deficits in early adolescents (11-13), though not in older teens (14-16) (Baumgartner, van der Schuur, Lemmens et al., 2017)

  • Neuroimaging research may account for these cognitive deficits
    • Heavy media multi-taskers require greater cognitive effort (increased activation of right prefrontal) to maintain concentration when faced with distractor stimuli (Moisala, Salmela, Hietajärvi et al., 2016)
    • Structurally, high levels of Internet usage and heavy media multi-tasking are associated with decreased gray matter in prefrontal regions associated with maintaining goals in face of distraction (e.g., right frontal and anterior cingulate cortex) (Kühn, Gallinat, & Brains, 2015; Loh & Kanai, 2014)
    • Even short-term engagement with an extensively hyperlinked online environment (e.g., online shopping for 15 minutes) reduces attentional scope for a sustained duration after coming offline
      • Reading a magazine does not produce these deficits (Peng, Chen, Zhao et al., 2018)

Memory #

  • Research has shown that the ability to access information online causes people to become more likely to remember where these facts could be retrieved rather than the facts themselves
    • Although storage of information online is beneficial at a group level, using this type of externally stored or “transactive memory” reduces an individual’s ability to recall the specifics of the externally stored information (Sparrow, Liu, & Wegner, 2011)
  • In addition, there is evidence that this is impairing people’s ability for analytical or critical thinking
    • If you know where to find the information (online) rather than the information itself, you’ll be worse off
    • Research has shown that analytical thinkers, with higher cognitive capacities, actually use their smartphone less for transactive memory in day-to-day situations compared to individuals with non-analytical thinking styles (Barr, Pennycook, Stolz et al., 2015)
    • May this in part explain the dramatic rise in popularity of conspiracy theories?!
  • Also, studies have found that increased reliance on the internet for information may cause individuals to “blur the lines” between their own capabilities and their devices’
    • Result is an over-inflation of self-perceived knowledge (Hamilton & Yao, 2018; Fisher, Goddu, & Keil, 2015)

Social cognitive effects #

  • Social media companies capitalize on people’s innate desire for positive feedback from others to maximally engage (and “addict”) users (e.g., via “friends,” “followers,” and “likes”)
    • However, growing evidence indicates that relying on online feedback for self-esteem can have adverse effects on young people, increasing anxiety and depression (Vannucci, Flannery, & Ohannessian, 2017; Lin, Sidani, Shensa et al., 2016)
  • In addition, the tendency to make upward social comparisons can be hijacked by the artificial environment manufactured on social media – no one really has a “Facebook life”!
    • This may lead to unrealistic expectations of oneself, poor body image, and negative self-concept, especially in younger people
  • Among adolescents (particularly females), those who spent more time on social media and smartphones have a greater prevalence of mental health problems, including depression (Twenge, Joiner, Rogers et al., 2017)
    • Compared with those who spend 1 hour/day, those who spend more than 5 hours/day had a 66% increased risk of a suicide-related outcome (Twenge, Joiner, Martin et al., 2018)

  • On the other hand though, the Internet may also potentially provide mental health benefits
    • As we will see later, AI programs have also been developed that can analyze Facebook or Instagram posts to effectively screen for depression and suicide risk (Eichstaedt, Smith, Merchant et al., 2018; Reece & Danforth, 2017)
    • Many types of online “virtual therapies” for mental illness are also being developed

Age Factor #

  • As discussed above, adverse attentional effects of digital multi-tasking are particularly pronounced in early adolescence (even compared to older teens)
  • In addition, higher frequency of internet use over 3 years in children has been linked to
    • Decreased verbal intelligence at follow-up and
    • Impeded maturation of both gray and white matter regions (Takeuchi, Taki, Asano et al. , 2018)
  • On the other hand, for older adults experiencing cognitive decline, Internet use may provide cognitive benefits
    • The online environment may provide a new source of positive cognitive stimulation
      • Studies have found that computer games available online and through smartphones can be used to attenuate aging-related cognitive decline (Kühn, Gleich, Lorenz et al., 2014; Anguera, Boccanfuso, Rintoul et al, 2013)
    • In addition, older adults may potentially be able to use social media to overcome isolation
      • This in turn enables them to reap the physical, mental and neurocognitive benefits associated with social connection (Wellman B., 2001)