Dude, what’s that smell?

U of T study explains link between smell and memory

Dude, what’s that smell?

I am sitting at my maternal grandmother’s house in New Delhi, India. Masi, my aunt, has prepared a dish for me that she promises I will love. I don’t particularly like surprises, but I wait outside the kitchen.

I catch a whiff of something sweet. I can’t place it but it’s familiar. I close my eyes and I know it’s a smell from my childhood. Then it hits me. My Masi is making an Indian confection called almond halwa using my grandmother’s recipe.

This connection that I made — that we all make — between odour and memories, is explained in a study published in Nature Communications. The study, led by Afif J. Aqrabawi, a PhD candidate in the Department of Cell & Systems Biology at U of T, sheds light on this connection and how it could help develop new diagnostic tests for Alzheimer’s disease.

The hippocampus (HPC) is essential to episodic memory. It organizes memories of sensory events, including smell, in terms of space and time. The HPC stores the condition of the brain when said events take place, and then retrieves and recreates cerebral cortex activity of the original memory’s context when we encounter the sensation again.

The anterior olfactory nucleus (AON) is the largest source of feedback projections in the olfactory cortex, and the anatomical junction where the connection between olfactory and contextual information is made. HPC projections into the AON can alter the way smells are perceived and what behaviours are associated with specific odours.

Aqrabawi and Department of Psychology Professor Jun Chul Kim had determined that inputs from the HPC to the AON are necessary for the retrieval of odour memory based on spatial and temporal contexts. They knew the AON played a role in connecting spatial and olfactory events, but they did not know the exact function of the AON-HPC junction.

Thereafter, Aqrabawi and Kim found a neural pathway between the HPC and AON and they were able to define its role in memory retrieval. This pathway is responsible for contextual retrieval of odours and is affected in patients with Alzheimer’s.

In the study, mice whose AON-HPC junction was blocked kept returning to investigate the same scent even after being exposed to it several times prior. This was an indication that the AON plays a significant role in memory retrieval.

On the other hand, mice whose junctions were left to function normally spent less time smelling familiar odours because of the episodic memories associated with them. Inhibition of the HPC-AON pathway results in a loss of the odour memory linked to a given context in space and time.

This is the first study that demonstrates that inputs from the HPC to the olfactory cortex are necessary for forming and retrieving episodic odour memories. Findings from the study also show that the anatomical location of AON behind the olfactory bulb is an ideal bridge between olfactory and contextual information.

Multiple studies have reported a loss of olfactory function in Alzheimer’s patients. In fact, diagnostic smell tests are currently used to detect the earliest symptoms of the disease. This olfactory dysfunction is due to the neurodegeneration of the AON, which stores episodic odour engrams, during the early stages of Alzheimer’s disease.

Future research involving these findings will likely aim to better understand the connection between smell and memory, and particularly the neural circuits involved in this association.

Using hand wipes can shift your goals

U of T study finds that cleansing affects not only physical domains but psychological ones as well

Using hand wipes can shift your goals

A new study by U of T PhD Student Ping Dong and Assistant Professor Spike W. S. Lee posits that hand wipes may be used for more than on-the-go cleaning. Their research, published in the Journal of Experimental Psychology earlier this year, revealed that physical cleansing reorients goals and shifts priorities.

Dong and Lee investigated four different groups ranging from 103 to 242 undergraduate students. The subjects were divided into two categories: those who were given hand wipes and those who were not. Both groups were primed to focus on certain goals by completing word games or short surveys.

The results of these four experiments demonstrated that the use of hand wipes made prior goals seem less important than subsequent ones. “This research extends the logic of previous studies showing that physical cleansing can reduce the influence of numerous psychological experiences,” Dong wrote in an email to The Varsity.

Dong and her colleague had observed certain behaviours relating to hand cleaning that inspired them to conduct this research. “Wash their hands, and people feel less guilty about their immoral behavior… Use some soap and people feel like they’ve washed away their good luck from their winning streak in gambling.”

“Our conceptual hypothesis was that there’s one common mechanism underlying all these different cleansing effects across domains,” Dong explained. “Specifically, cleansing should function as what we call an ‘embodied procedure of psychological separation.’”

Physical cleansing detaches traces, such as dirt, from target objects, like hands. This resembles the psychological separation of previous experiences from the present self. Dong and Lee’s research provided evidence supporting this theoretical account in the context of pursuing goals.

Their paper, unlike its predecessors, shows “that a bodily experience like cleansing not only activated metaphorically associated concepts like morality, but functions as a highly domain-general procedure.” This means that cleansing is not specific to physical domains, but also influences psychological ones.

The research predicts that using hand sanitizers, wipes, or other forms of physical cleansers will ease the switch between tasks that require different mental procedures. “[People] become less influenced by past primes but more influenced by future ones,” Dong said.

The study has some limitations, according to Dong. The participants were solely undergraduate students, rather than the general public. The importance of goals was measured immediately after physical cleansing so the short-term nature of the experiment may have also restricted its results. Long-term effects were not examined.

Dong, who will join Northwestern University’s Kellogg School of Management as an assistant professor of marketing in September 2017, emphasized that in business settings or organizations, both the managers and employees must often shift between several goals.

“Little help is available from empirical work, as it has yet to identify any temporary manipulation for enhancing [the] ability [to shift between multiple tasks],” she said. “Given what we found, we suggest that physical cleansing may be a handy way to help people adjust their goal pursuit effectively.”

Mind Matters hosts sixth annual conference at Isabel Bader Theatre

Eminent scientists, psychologists, discuss medicinal use of psychedelics

Mind Matters hosts sixth annual conference at Isabel Bader Theatre

The sixth annual Mind Matters conference, hosted by U of T’s Buddhism & Psychology Students’ Union in conjunction with the U of T Jungian Society, took place last Saturday morning at Victoria College’s Isabel Bader Theatre. Titled “Altered States,” this year’s event brought a group of reputed scientists and thinkers together to engage in a lively intellectual discussion on the implications of psychedelics in medicine and psychology. 

The psychology conference, which attracted a full house audience and required almost 40 staff to organize, is the largest of its kind in Canada. Despite the packed house, Ammar Ijaz, one of the many student organizers, described it as a “community” gathering.  General admission tickets for the event sold out within six hours of being made available, while the supply of student tickets was exhausted after thirteen minutes.

Panelists for the event included Professors Dan Dolderman, John Vervaeke, and Jordan Peterson, all prominent thinkers in the field of psychology. American ethnopharmacologist Dennis McKenna joined the U of T lecturers on stage. The focus of this year’s conference revolved around altered states of consciousness. Topics of discussion included psychedelic medicine, meditation, lucid dreams, trance states, and mystical experiences.

The award winning lecturer, Professor Vervaeke, who is a five-time veteran of the conference, opened the conference with an exploration of what he described as the “meaning crisis of modernity.” Vervaeke invoked and interpreted the likes of Friedrich Nietzsche and other philosophers by way of delivering his point, observing a fundamental difference between wisdom and knowledge, ultimately concluding, “knowledge is about overcoming ignorance, wisdom is about overcoming foolishness.” He ended his presentation to a round of applause with an endorsement of the pursuit of altered states of mind for their potential to enhance human understanding and consciousness.

Professor Dolderman picked up after a brief intermission and schedule change. “This talk,” he said, “is a call to awakening … a call to battle” he exclaimed. “There is no altered state,” he said. “I’m not interested in ethics or morals. I’m interested in how I experience the world;” adding that, “we feel first, then reason later [but we] don’t feel deeply enough.” 

By listing a series of everyday interactions with seemingly mundane ideas and objects such as steaks, eggs, the War on Terror, and the economy, Dolderman argued that, “what we experience isn’t exactly the real world. Not experientially but rather simply intellectually.” Steaks do not magically become slabs of meat on our dinner plates. Rather, the reality is the mistreatment of cows. Wars are as connected to freedom and liberty as they are to death, he observed.

The speakers each presented academic theories on the potential of psychedelics in psychology and medicine, informed by current research and elucidated through term definitions and analogies, to a visibly engaged audience. Discussion on stage was supplemented with lively social media engagement, moderated by a dedicated team of volunteers, through the use of an official Mind Matters Twitter hashtag,

The event was initially supposed to consist of five speakers with intermissions for coffee, a provided lunch, and an interactive panel discussion. Unfortunately, a slight change of schedule was required since one of the speakers, Lee Maracle, fell ill and was unable to attend.

In a post-event interview, an exhausted, but pleased, Ijaz described some of the challenges he faces every year in organizing the conference. “Funding is always a big challenge.” This year, they were able to crowd fund a quarter of the projected conference costs. They were also successful in acquiring sponsorship for subsided student tickets.

Ijaz expressed his surprise at how quickly the event sold out. They had hoped to find a venue for 1,000 attendees, but were unable to find the necessary funding. He also drew attention to the conference organizers’ efforts to bring a broad range of perspectives to the selection of the event’s speakers after a comment on Twitter criticized the conference’s lack of visible diversity.  “We strive for incredible diversity,” noted Ijaz, though he conceded that, despite their best efforts, the event fell a “little bit short of the mark.”

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Editor’s Note (March 10th, 2016): An earlier version of this article misattributed a quote to David Taylor.