Perché ci accorgiamo di esistere? La lezione di Giorgio Vallortigara | Lucy - Sulla cultura

Summary

The provided transcript delves into the intricate and central issue of today's neuroscience: understanding consciousness. Giorgio Vallortigara, a neuroscience professor at the University of Trento, challenges two prevailing misconceptions. First, he disputes the idea that consciousness automatically emerges with increased complexity of the nervous system, emphasizing that complex cognitive activities can occur without conscious experience. Second, he criticizes the notion of degrees of consciousness, suggesting a clear divide between entities that lack experience, like stones, and those, even the simplest animals, that do have some form of sensation. Vallortigara explores the concept of 'blind sight,' where individuals demonstrate perception without conscious awareness, drawing parallels to philosophical zombies—beings that act normally without any accompanying experience. He suggests that our mental life is like an iceberg, with most of our cognitive activity unconscious, and only a small part conscious. The discussion also touches on the evolutionary perspective, considering the necessity and origin of conscious feelings. The potential origins of consciousness are linked to the active movement of early organisms and the differentiation between self-generated stimuli and external ones, a mechanism known as efference copy. This concept is pivotal in discerning between internal and external events, which could be the starting point of conscious experience. The transcript concludes by contemplating the future of artificial intelligence and whether machines could be made conscious by emulating biological organisms' active engagement with the world.

Takeaways

• 🧠 The central issue in modern neuroscience is understanding consciousness and how physical and chemical brain events transform into our conscious experiences.
• 🤔 Common misconceptions include the idea that consciousness automatically emerges with increased complexity of the nervous system, which is disputed due to evidence of complex mental operations without conscious experience.
• 🚫 The notion of varying 'degrees' of consciousness is also questioned, as there is believed to be a clear divide between entities that lack experience, like stones, and those that have some form of sentience, like animals.
• 🔬 Neuroscience studies how the brain and nervous system of various animal species produce psychological processes such as perception, attention, memory, and learning.
• 🧐 The term 'consciousness' is polysemous and can mean different things to different specialists, from anesthesiologists to theologians, and is often associated with the feeling aspect of our mental life.
• 📚 There are many examples of learning and memory in everyday life where we are not consciously aware of how we acquired certain skills or knowledge, such as learning to keep a broomstick balanced on the hand.
• 🧬 Neuroscientific studies have shown that even animals can perform complex cognitive tasks without necessarily being conscious of them, challenging the assumption that cognitive complexity equates to consciousness.
• 🧵 The concept of 'blind sight' in humans, where individuals can respond accurately to visual stimuli without consciously seeing them, suggests that there is a distinction between perception and the conscious feeling of sensation.
• 🐦 The experimental study of animals, like the case of the monkey Helen, demonstrates that even with significant brain damage, animals can adapt and perform tasks that seem to require vision, indicating complex processing without conscious awareness.
• 🧵 The theory that the mechanism of efference copy, which is a concept where the brain sends a copy of a motor command to the sensory system, might be the starting point for conscious experience, as it allows for the distinction between self-generated actions and external stimuli.
• 🤖 When considering artificial intelligence, the discussion suggests that for a machine to become conscious, it would need to have a body and interact actively with the world, similar to biological organisms, to encounter the problem of distinguishing between self-generated sensations and external perceptions.

Q & A

What is the central issue in neuroscience today regarding consciousness?

The central issue in neuroscience today is understanding what consciousness is and how physical and chemical events in the brain are transformed into our conscious experience of things we see, hear, and so on.

Why does the speaker believe that consciousness does not automatically emerge with the complexity of the nervous system?

The speaker believes this idea is incorrect because it confuses conscious experience with complex cognitive activity. There is evidence that humans and other animals can perform complex mental operations without conscious experience, indicating that the two are not inherently linked.

What is the concept of 'degrees of consciousness' that the speaker finds implausible?

The concept of 'degrees of consciousness' suggests that there are varying levels of consciousness, which the speaker finds implausible. He argues that there is a clear distinction between things like stones that do not have experience and animals that do, even the simplest ones.

How does the speaker describe the term 'consciousness'?

The speaker describes 'consciousness' as a polysemous term, meaning it can have different interpretations depending on the specialist's perspective. For instance, an anesthesiologist might refer to it in terms of a patient's awareness, while a theologian might discuss moral consciousness.

What is the 'hard problem' of consciousness as mentioned by the speaker?

The 'hard problem' of consciousness, as mentioned by the speaker, refers to the challenge of understanding why and how certain aspects of our behavior or mental life are accompanied by our feeling something or experiencing something, which is sometimes called 'feeling'.

What is the phenomenon of 'blindsight'?

Blindsight is a phenomenon where patients with damage to their primary visual cortex can accurately guess the location and sometimes the identity of objects in their visual field that they claim not to see. It suggests that there is a form of vision without awareness.

How does the speaker relate the concept of cognitive unconsciousness to an iceberg?

The speaker relates cognitive unconsciousness to an iceberg by suggesting that most of our mental life, like the bulk of an iceberg, is submerged and not visible (unconscious). Only a small part, the tip of the iceberg, represents conscious mental life.

What is the significance of the distinction between sensation and perception?

The distinction between sensation and perception is significant because it allows for the understanding that one can perceive an object without having a conscious sensation associated with it, as seen in cases of blindsight and agnosia.

What is the 'efference copy' mechanism?

The 'efference copy' mechanism is a concept where the brain sends a copy of the motor command to the sensory system to alert it that the upcoming sensation is due to one's own movement, thus preventing the sensation of self-tickling or the awareness of self-generated stimuli.

How does the speaker suggest the mechanism of efference copy might be related to mental disorders such as schizophrenia?

The speaker suggests that certain positive symptoms of schizophrenia might be associated with a disruption in the efference copy mechanism, leading to patients perceiving their own thoughts as if they belonged to someone else, questioning the authorship of their thoughts.

What is the speaker's view on the possibility of artificial intelligence achieving consciousness?

The speaker believes that for artificial intelligence to achieve consciousness, they would need to have a body and actively interact with the world, similar to biological organisms. This active interaction would allow them to encounter the problem of distinguishing between self-generated sensations and external stimuli, potentially leading to conscious experience.