Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Reptile brains respond to music
#11
The study wasn't about their response to music per say, but rather was about assessing their neurobiology and seeing how the brain specifically processes the information, both simple and complex, auditory and visual, to provide an insight into the evolution of such abilities. Seeing as the stem ancestor of birds and mammals is no longer around to study, the next best option is the crocodilian as they seem to have changed little over the last 200 million years so represent an animal that lived fairly close to the time of the reptile-mammal split, and also has very close evolutionary ties with birds (cousins), so likely share some common traits inherited from a common ancestor. Classical music was chosen for the role of complex audio stimuli because of its fast amplitude changes and broad spectrum frequencies, allowing for the investigation of how the brain responds to complex noise. It's a study on evolutionary biology, that provides interesting insight into when certain neurological features first arose, which ones are commonly inherited and which are independently evolved within their respective taxa.

The conclusion being many neurological features appear to have developed early in the evolution of tetrapods, meaning reptiles, mammals and birds are more alike than previously suspected.
Reply
#12
Quote:The conclusion being many neurological features appear to have developed early in the evolution of tetrapods, meaning reptiles, mammals and birds are more alike than previously suspected.

I would think a lot of basic things developed very early in the evolution of tetrapods. The brain has continued to evolve, but I would expect basic patterns to be there early on. We have a more complex response to music because our brains are far more complex. We recognize the patterns in the sounds. Still the more primitive brain would have needed the ability to react to complex sounds.
The roots of our music appreciation are probably there in the crocodilian brain.

It would be interesting to know how the dinosaur brain developed in this and other areas. That would be one good reason for cloning them(if it is even possible).
[Image: IMG_9091.JPG]
Catherine

Reply
#13
The study wasn't about whether they had the ability to process the information but specifically how neural processing is conducted. For instance, in mammals, the hippocampus is responsible for spatial cognition, reptiles lack a hippocampus so an alternate system is required - in reptiles it is the medial cortex thats responsible for spatial cognition. In this instance mammals had developed a trait independent to the reptiles. The Hippocampus is not a cognitive trait inherited from a common ancestor, although mammalian ancestors would have likely relied on a structure like the medial cortex.

Also it's worth noting that modern reptiles and mammals have been evolving at the same rate, there has been ample time for changes to occur since the time of the common ancestor, no animal is more evolved than another and any cognitive feature is a result of the environment the animal lives in. E.g. an animal living in one type of environment with specific environmental pressures can not be expected to have the same cognitive processes as an animal living in a completely different environment with different demands placed upon it. 

Regarding dinosaurs, in the abstract of the study they actually write "Our results indicate that structural and functional aspects of sensory processing have been likely conserved during the evolution of sauropsids." Meaning dinosaurs had likely inherited the original structuring of ancestral neurocircuitry, which seems to have been passed on to their descendants, the birds.


The response to music specifically is a completely independent matter and wasn't the concern of this study. As i've explained already, the ability to comprehend music is linked to development of complex communication systems. This doesn't indicate that the animal is more evolved but rather that they have been shaped by the need to communicate more efficiently as a consequence of relying on complex social living to survive. Living in less complex social group or solitary lifestyles are just as valid evolutionary pathways if the trait benefits survival in that particular environment.

I think the only way to possibly get a dinosaur is by reverse engineering a chicken as no genetic material exists beyond what's retained in the descendants of dinosaurs (birds). They've already located the dormant gene for teeth in chickens as well as successfully activated the genes for dinosaur leg development. I would love the opportunity to photograph a dinosaur lol, they were likely highly ornate and colourful animals.
Reply
#14
I couldn't get back to the original article. The link didn't work for me. So I have found another article about the same experiment.

https://asgardiaspacenews.com/crocodiles...-to-music/


Quote:The findings, published in the journal Proceedings of the Royal Society B, demonstrate that the crocodile’s brain responded to the music in a similar way to how birds’ brains respond. It’s quite interesting that they have similar responses seeing as birds make their own songs and crocodiles don’t.

This study marks the first time scientists have examined the brain of a cold-blooded animal like a reptile using an fMRI, according to Gizmodo. These findings suggest that responding to music, or at least complex sounds like birdsong or Bach, is deeply wired into the animal brain, spanning across mammalian, avian, and reptilian brains. Seeing as crocodiles have  hardly changed since the time of the dinosaurs, this study highlights the possibility that this trait has been in animal brains for hundreds of millions of years.
I think the key point is the fact that the crocodile brain responded in a way that is similar to birds. They are suggesting that response to music or at least response to complex sound could be a trait that has been around for a very long time.

Since the crocodile was sedated they were observing how the brain reacted. The crocodile was not consciously responding to the music.

This study is a starting point for a lot of further studies.  There are other species that have been around a long time unchanged. It would be interesting to see how their brains respond to music.
Until further study is done there wasn't enough information gained to make any big conclusions.
Really they are just suggesting that the trait of responding to music could have been around for hundreds of millions of years.

We have clearly evolved the trait to a high degree, but the roots of the trait may go back to a common ancestor in the distant past. It is too early to draw actual conclusions.

Quote:I think the only way to possibly get a dinosaur is by reverse engineering a chicken as no genetic material exists beyond what's retained in the descendants of dinosaurs (birds). They've already located the dormant gene for teeth in chickens as well as successfully activated the genes for dinosaur leg development. I would love the opportunity to photograph a dinosaur lol, they were likely highly ornate and colourful animals.
It wouldn't be easy and it might not really be a proper dinosaur, but still it would be interesting.
[Image: IMG_9091.JPG]
Catherine

Reply
#15
Just to clarify, (for anyone who might read this thread) this is the original study; 

Behroozi, M., Billings, B. K., Helluy, X., Manger, P. R., Güntürkün, O., and Ströckens, F., (2018). Functional MRI in the Nile crocodile: a new avenue for evolutionary neurobiology. Proceedings of the Royal Society B: Biological Sciences. 285, (1877).

The link to the full study can be found here:
http://www.bio.psy.ruhr-uni-bochum.de/pa...20fMRI.pdf

The problem with blogs is that because they're relaying on information that's second hand, or sometimes from other blogs, its easy for information to get slightly misconstrued, in this instance there's an over-focus on the fact that music was used for the study. 


The study wasn't about response to music but to investigate the functional aspects of the brain to further understand the evolutionary neurobiology of amniotes and the investigation of shared and divergent features.


The abstract reads:...

"Crocodilians are important for understanding the evolutionary history of amniote neural systems as they are the nearest extant relatives of modern birds and share a stem amniote ancestor with mammals. Although the crocodilian brain has been investigated anatomically, functional studies are rare."


So we're aware that structurally there are some differences between reptiles, mammals and birds, particularly notable is how basic in structure the reptilian brain is compared to the more complex structuring of bird and mammals brains but functionality was still not known before the results of this study. The sub-telencephalic sensory regions have remained similar in structure and function in all vertebrates. The telencephalon, however, has undergone significant modifications, leading to a layered, cortical organisation of the pallium in mammals and a non-layered, nuclear pallium in birds. Due to their anatomical differences investigation into how this region functioned was conducted as it was not known if functionality was the same as there were quite a few anatomical differences. The abstract continues...



"Here, we employed functional magnetic resonance imaging (fMRI), never tested in poikilotherms, to investigate crocodilian telencephalic sensory processing. Juvenile Crocodylus niloticus were placed in a 7 T MRI scanner to record blood oxygenation level-dependent (BOLD) signal changes during the presentation of visual and auditory stimuli. Visual stimulation increased BOLD signals in rostral to mid-caudal portions of the dorso-lateral anterior dorsal ventricular ridge (ADVR). Simple auditory stimuli led to signal increase in the rostromedial and caudocentral ADVR. These activation patterns are in line with previously described projection fields of diencephalic sensory fibres. Furthermore, complex auditory stimuli activated additional regions of the caudomedial ADVR. The recruitment of these additional, presumably higher-order, sensory areas reflects observations made in birds and mammals. Our results indicate that structural and functional aspects of sensory processing have been likely conserved during the evolution of sauropsids. In addition, our study shows that fMRI can be used to investigate neural processing in poikilotherms, providing a new avenue for neurobiological research in these critical species."



The reason why simple and complex sound was used is because the brain doesn't process these different sounds the same way. The introduction reads:

"In both classes (mammals and birds), sensory information reaching the pallium is processed in a hierarchical fashion, with relatively simple stimuli activating downstream, or lower-order, regions within the sensory pallium, while presentation of more complex stimuli leads to the recruitment of additional higher-order regions upstream. Consequently, simple auditory stimuli, like pure tones, only activate auditory core regions within the temporal lobe of primates or the nidopallial Field L of songbirds, while more complex stimuli, like music or vocalizations, also activate the temporal belt and parabelt regions in primates and the caudomedial nidopallium (NCM) in birds. These functional similarities appear to have been conserved despite the obvious gross anatomical differences of the telencephalon between these classes and the phylogenetic distance between them."



Even though the study wasn't specifically about reptilian appreciation for music it was still an interesting and important study for understanding the evolutionary history of amniotes.
Reply
#16
The issue was never about reptiles appreciating music. It was about a crocodile brain (therefore a primitive brain) showing a response to  music/complex sound on an MRI. Until more animals of different reptile species are studied it is a bit early to draw any definite conclusions.

I wonder how a turtle brain would respond. I wonder what differences there would be between the land turtles and an aquatic turtle, in particular ocean turtles.

We will have to wait until further studies are done to know the answer.
[Image: IMG_9091.JPG]
Catherine

Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)
Created by Zyggy's Web Design