Philosophy Now Forum

ChatGPT wrote:The concept of the Triune Brain, proposed by neuroscientist Paul D. MacLean in the 1960s, suggests that the human brain can be divided into three main components: the reptilian brain (or reptilian complex), the limbic system, and the neocortex. While this theory has gained some popularity and has been influential in the past, it is important to note that it is not universally accepted among neuroscientists today.

Critics argue that the Triune Brain model oversimplifies the complexity of the brain's structure and function. They argue that it does not accurately reflect the interconnectedness and integrated nature of brain regions and their functions. Additionally, the model implies a strict evolutionary progression from reptilian to mammalian to human brains, which is not supported by current understanding of brain evolution.

However, some aspects of the Triune Brain concept can still be considered useful or informative when used with caution. For example, the idea of the limbic system, which encompasses structures involved in emotions and motivation, including the amygdala and hippocampus, has been widely accepted and studied in neuroscience.

Moreover, Robert Sapolsky, the neuroscientist .........., is known for his work on stress and the effects of stress on the brain. In his presentations and writings, he often refers to the Triune Brain model as a simplified framework to explain certain aspects of human behavior, particularly in relation to stress responses.

While the Triune Brain concept may have limitations, it can still serve as a pedagogical tool or a starting point for discussions about brain anatomy and function.
However, it is important to recognize its limitations and not to interpret it as a comprehensive or definitive model of brain organization.

Veritas Aequitas wrote: ↑Sun Jun 25, 2023 8:06 am Whenever I introduced the concept of the Triune Brain as a basis for Morality in some ways, some will jump at it with some links to insist it is absolutely out-dated.

I believe such attitude is very unintelligent, given the concept of the Triune Brain is not obvious trash.

The intelligent should know what to pick as useful subject to the known limitations and reject the irrelevant.

Peter Holmes wrote: ↑Sun Jun 25, 2023 11:49 am Elsewhere, VA has posted about the triune brain theory, with no overt reference to morality. Here's a response.

I suggest the triune brain theory is a nice example of reverse-theorising, as follows.

We have distinct mental faculties, within which perceiving, thinking, feeling, willing, intending, and so on, go on. But, given physicalism, these so-called mental processes must occur in discreet parts of the brain.

But the 'higher mental faculties' aren't present in the brains of pre-human life forms, from which humans evolved.

Therefore, part of the human brain is 'reptilian' (the basal ganglia, dealing with basic biological needs and primal instincts), part is 'paleo-mammalian' (the limbic system, dealing with emotions), and part is 'neo-mammalian' (the neocortex, dealing with objective or rational thoughts).

The attraction of this theory for VA is obvious: the human brain is organised physiologically to deal with different aspects of human life; therefore, 'morality' is programmed, somehow, into the human brain.

The conceptual influence of faculty psychology - and mentalism in general - on neuroscience is itself a fascinating issue. 'We have thoughts; therefore, this physical phenomenon is 'a thought'. '

ChatGPT wrote:The human brain possesses several distinct functions that are generally considered more advanced or uniquely developed compared to other animals. Some of these functions include:

Language and Communication: Humans have highly developed language abilities, allowing for complex communication through spoken and written words. While other animals may have their own forms of communication, human language is unique in its complexity and ability to convey abstract concepts.

Symbolic Thinking and Abstract Reasoning: Humans have the capacity for symbolic thinking, enabling the use of symbols and abstract concepts to represent and manipulate information. This ability is fundamental to various cognitive processes such as mathematics, art, and conceptual reasoning.

Metacognition: Humans have the ability to reflect on their own thoughts and think about thinking, known as metacognition. This includes self-awareness, introspection, and the ability to monitor and regulate one's own cognitive processes.

Future Planning and Mental Time Travel: Humans have the capacity to mentally project themselves into the future, plan ahead, and anticipate consequences. This ability for mental time travel enables us to consider future scenarios and make decisions based on long-term goals.

Theory of Mind: Theory of mind refers to the ability to understand that others have beliefs, desires, and intentions that may differ from one's own. Humans have a well-developed theory of mind, allowing us to attribute mental states to others and infer their thoughts and perspectives.

Executive Functions: Humans possess advanced executive functions, including the ability to inhibit impulses, plan and organize behavior, set goals, and adapt to changing circumstances. These functions play a crucial role in decision-making, problem-solving, and self-control.

While these functions are often considered unique to humans, it's important to note that other animals possess their own cognitive abilities and may exhibit similar but less developed versions of these functions. The degree and complexity of these functions can vary across different species, reflecting their specific evolutionary adaptations and ecological niches.

Veritas Aequitas wrote: ↑Mon Jun 26, 2023 7:56 am From the observations of physical brains from brains [nervous system] of different species, it is obvious there are distinct separate parts.

Veritas Aequitas wrote: ↑Mon Jun 26, 2023 9:53 am There are various meanings to the term 'distinct'.

My use of 'distinct' in this case is something like,'
the head is distinct from the body [torso] and legs in terms of features.
As such it does not mean the body is a separate part and unattached to the body.

It is the same when I stated the human brain has 3 distinct parts which can be seen easily but they are all interconnected between each other and to the body.

With the current knowledge of neurosciences, it would be very stupid of me to claim there are 3 independent separate parts of the brain.

Veritas Aequitas wrote: ↑Tue Jun 27, 2023 6:26 am Strawman.

I stated;
With the current knowledge of neurosciences,
it would be very stupid of me to claim there are 3 independent separate parts of the brain.

Veritas Aequitas wrote: ↑Mon Jun 26, 2023 7:56 am
From the observations of physical brains from brains [nervous system] of different species, it is obvious there are distinct separate parts.

I don't claim to be that stupid.
Therefore I believe the nervous system with the brain and parts identified as distinct are all interconnected by neurons and synapses.

In addition, it is possible for the brain and its parts to interact and work via quantum processes rather than direct physical connections.

Agent Smith wrote: ↑Tue Jun 27, 2023 6:38 am One poster seems unconvinced by David Maclean's theory and although he has quite a good reason for his skepticism, we could counter his argument by calling to our aid a very well-worn distinction.

Theory impacts how research is conducted. A popular theory used to conceptualize brain functioning is the triune brain theory. The triune brain theory is an evolutionary theory of brain development that emphasizes three key brain regions consisting of the brainstem, the limbic system, and the cortex that function relatively independently in coping with stress via fight or flight, emotion, and cognition, respectively. However, modern neuroscience research demonstrates that the triune brain theory does not accurately explain how the brain functions in everyday life or during the stress response. Specifically, emotion and cognition are interdependent and work together, the limbic system is not a purely emotional center nor are there purely emotional circuits in the brain, and the cortex is not a purely cognitive center nor are there purely cognitive circuits in the brain. We propose a new evolutionarily based model, the adaptive brain, that is founded on adaptive prediction resulting from interdependent brain networks using interoception and exteroception to balance current needs, and the interconnections among homeostasis, allostasis, emotion, cognition, and strong social bonds in accomplishing adaptive goals.

But according to Terrence Deacon, Ph.D., an expert on the evolution of human cognition at the University of California, Berkeley, subsequent research has revealed that MacLean’s basic premise—his “‘hats on top of hats’ view” that brain systems were added by accretion over the course of evolution—was mistaken. “Adding on is almost certainly not the way the brain has evolved,” said Deacon. “Instead, the same structures have become modified in different ways in different lineages.”

MacLean proposed his (incorrect) theory after he made some curious observations about the effects of cutting out what he called the “reptilian complex” of a monkey’s brain (so named because he thought it looked similar to the tissue that made up most of a reptile’s brain). When MacLean took out this part of a male monkey’s brain, the monkey stopped aggressively gesturing at its own reflection (which it thought was another male monkey). This behavioral change seemed to fit MacLean’s hunch that he had taken out a “reptile”-like part of the monkey’s brain, since he thought that aggressive gesturing is a typical example of “reptilian behavior.”

It’s unclear why cutting out this part of the monkey’s brain made the monkeys stop showing aggressive displays, but this brain area, more commonly called the globus pallidus, is known to be involved in an enormous variety of processes. Also, to my knowledge, MacLean’s original observations have not been replicated. What’s more, MacLean’s claim about the prominence of the globus pallidus in the reptilian brain is false: it forms just one part of reptiles’ brains, exactly as it does in the monkey brain.

Based on these loose observations, MacLean argued that we might have a “lizard” brain inside of our brain. In other words, he thought that we never got rid of the “reptilian” brain we inherited from our reptile ancestors, but instead evolved new brain structures on top of our old reptile brain.

Based on these shaky foundations, together with other loose observations regarding what he considered to be uniquely mammalian behavior, MacLean went on to develop a full-blown theory of human brain evolution. The theory held that inside our brains there is a primitive reptilian complex, which is surrounded by an “old” mammalian structure called the limbic system, which is itself surrounded by a “new” mammalian structure called the neocortex. The neocortex was, MacLean asserted, the crowning jewel of brain evolution – the structure, in other words, which made humans (and perhaps other intelligent mammals) unique.

Iwannaplato wrote: ↑Tue Jun 27, 2023 8:20 am

Agent Smith wrote: ↑Tue Jun 27, 2023 6:38 am One poster seems unconvinced by David Maclean's theory and although he has quite a good reason for his skepticism, we could counter his argument by calling to our aid a very well-worn distinction.

One certainly could. But given that the context is a discussion with someone who refers to FSKs, the relevant FSK is neuroscience. And the consensus of neuroscientists no longer believe in the Truine Brain.

You and I could have another discussion, of course, because it is less clear where you are coming from.

We have refereces such as....
https://www.frontiersin.org/articles/10 ... 20response.

Theory impacts how research is conducted. A popular theory used to conceptualize brain functioning is the triune brain theory. The triune brain theory is an evolutionary theory of brain development that emphasizes three key brain regions consisting of the brainstem, the limbic system, and the cortex that function relatively independently in coping with stress via fight or flight, emotion, and cognition, respectively. However, modern neuroscience research demonstrates that the triune brain theory does not accurately explain how the brain functions in everyday life or during the stress response. Specifically, emotion and cognition are interdependent and work together, the limbic system is not a purely emotional center nor are there purely emotional circuits in the brain, and the cortex is not a purely cognitive center nor are there purely cognitive circuits in the brain. We propose a new evolutionarily based model, the adaptive brain, that is founded on adaptive prediction resulting from interdependent brain networks using interoception and exteroception to balance current needs, and the interconnections among homeostasis, allostasis, emotion, cognition, and strong social bonds in accomplishing adaptive goals.

https://medicine.yale.edu/news/yale-med ... ompelling/

But according to Terrence Deacon, Ph.D., an expert on the evolution of human cognition at the University of California, Berkeley, subsequent research has revealed that MacLean’s basic premise—his “‘hats on top of hats’ view” that brain systems were added by accretion over the course of evolution—was mistaken. “Adding on is almost certainly not the way the brain has evolved,” said Deacon. “Instead, the same structures have become modified in different ways in different lineages.”

https://thebrainscientist.com/2018/04/1 ... ard-brain/

MacLean proposed his (incorrect) theory after he made some curious observations about the effects of cutting out what he called the “reptilian complex” of a monkey’s brain (so named because he thought it looked similar to the tissue that made up most of a reptile’s brain). When MacLean took out this part of a male monkey’s brain, the monkey stopped aggressively gesturing at its own reflection (which it thought was another male monkey). This behavioral change seemed to fit MacLean’s hunch that he had taken out a “reptile”-like part of the monkey’s brain, since he thought that aggressive gesturing is a typical example of “reptilian behavior.”

It’s unclear why cutting out this part of the monkey’s brain made the monkeys stop showing aggressive displays, but this brain area, more commonly called the globus pallidus, is known to be involved in an enormous variety of processes. Also, to my knowledge, MacLean’s original observations have not been replicated. What’s more, MacLean’s claim about the prominence of the globus pallidus in the reptilian brain is false: it forms just one part of reptiles’ brains, exactly as it does in the monkey brain.

Based on these loose observations, MacLean argued that we might have a “lizard” brain inside of our brain. In other words, he thought that we never got rid of the “reptilian” brain we inherited from our reptile ancestors, but instead evolved new brain structures on top of our old reptile brain.

Based on these shaky foundations, together with other loose observations regarding what he considered to be uniquely mammalian behavior, MacLean went on to develop a full-blown theory of human brain evolution. The theory held that inside our brains there is a primitive reptilian complex, which is surrounded by an “old” mammalian structure called the limbic system, which is itself surrounded by a “new” mammalian structure called the neocortex. The neocortex was, MacLean asserted, the crowning jewel of brain evolution – the structure, in other words, which made humans (and perhaps other intelligent mammals) unique.

Leaping to conclusions was MacLean's watchword.

Agent Smith wrote: ↑Tue Jun 27, 2023 1:02 pm I see. How so very disappointing. I had grown to like Maclean's theory - it is a theory, oui?

Nevertheless, I was very specific with regard to the criticism I offered. Truth is, I really had no choice but to say what I did.

Iwannaplato wrote: ↑Tue Jun 27, 2023 2:32 pm

Agent Smith wrote: ↑Tue Jun 27, 2023 1:02 pm I see. How so very disappointing. I had grown to like Maclean's theory - it is a theory, oui?

I'd call it a hypothesis, though I did call it a theory earlier.

Nevertheless, I was very specific with regard to the criticism I offered. Truth is, I really had no choice but to say what I did.

No worries, not that I understood that criticism. In any case, one could take his theory as a metaphor. And it shares things with Freud's tripartite schema: id (really 'it'), ego and superego.

Gotta love the id. Integrate! don't suppress or 'dam'!
That's the ticket.