Fears and ageing: UniBo study investigates the correlation between them
What are the mechanisms underlying fear? And how do they change during lifetime? A study conducted at the University of Bologna, recently published in the journal Scientific Reports, answers these questions.
The study shows that elderly people have more difficulty in assessing danger signals as they are more likely to become frightened even in environments considered safe.
The researchers focused on the role of memories in triggering an alarm response. “Memories of traumatic experiences are never permanently removed from our brains. For this reason, stimuli and events related to dangerous situations experienced in the past can, under certain circumstances, trigger anxiety and fear”, explained Giuseppe di Pellegrino, a Professor at the University of Bologna, who led the study. “In potentially dangerous environments, the context can act as a warning signal while in safer environments it can inhibit the emergence of unpleasant memories”, the scientist continued.
But how does this mechanism work? To investigate the role played by context in activating unpleasant memories and triggering fear, researchers Simone Battaglia, Sara Garofalo and Giuseppe di Pellegrino carried out a study at the Centre for Studies and Research in Cognitive Neuroscience of the University of Bologna.
The study was conducted on 48 people divided into two age groups: 24 were aged 20 to 30 years, and 24 were aged 60 to 70 years. The experiments were conducted on two consecutive days.
On the first day, participants were initially induced to associate, in one room, a neutral stimulus – the image of a plant – with an electric shock to the wrist. All the participants, understandably, reacted to these associations showing physiological responses to fear.
Subsequently, in a different room, participants were presented with the image of a plant, this time without electric shock: in this context, the participants’ physiological responses related to fear gradually disappeared.
On the second day, participants were presented with the image of the plant in both the first and second rooms. This time, however, the old group, unlike the young group, showed reactions to fear in both contexts.
“These results tell us that ageing can have a negative impact on the ability to process contextual information to flexibly modulate the retrieval of emotional memories. This could be due to age-related changes in certain areas of the brain, such as the hippocampus and the prefrontal cortex, which are particularly sensitive to the effects of ageing”, di Pellegrino concluded.