The Next Big Thing About the Cerebellum Might Open Frontiers In Understanding The Brain

The cerebellum, which in Latin means “the little brain,” is at the hindbrain in all vertebrates. North of the cerebellum is the cerebral cortex which forms its outer layer. Formerly, due to its folding nature, the cerebellum was thought to be smaller than the cerebral cortex and so not much involved in as much activities in human behavior and cognition as the cortex. But recent research has disproved that point.

The cerebellum as earlier said was thought to be smaller because it is arranged in hundreds of folds which make it look small in surface area but researchers using ultra-high-field MRI imaging together with specialized software have found that the surface of the cerebellum is much larger than was believed. It was even found to be even bigger than the cerebral cortex. It is now said to be approximately more than 80 percent of the cerebral cortex.  

This research would now open the way for more research into the benefits of the cerebellum for human behavior and cognition. This is because since the cerebellum is bigger than the cortex, it shows that human evolution is more advanced than other vertebrates, even those closer to man like the macaque monkeys. Therefore, it will help us to understand how over the years man has adapted better than other vertebrates to the environment and has used the advantage afforded it by a bigger cerebellum to develop advanced levels of cognitive abilities.

The researchers also found that while the cerebral cortex was well arranged and the body parts they were controlling well defined, that is not the case for the cerebellum. The cerebellum receives information from disparate parts of the body in a random manner. That means, areas for coordinating the shoulder could lie side by side with areas coordinating the foot. This gives humans the advantage over other animals of coordinating different body parts all at the same time from one central location, enhancing efficiency.

Also, the researchers found that the cerebellum must have a higher role in controlling emotional responses more than was earlier thought. It is established that the cerebellum is involved in movement-related functions, but this study also delved into the study of damaged cerebellums and found that people with such challenges had problems understanding their emotions. But further research has to be done in this area.

In the coming years, with the results from the MRI study, researchers will be able to better understand how the brain works and not confine their knowledge to thinking the control of body functions is limited to specific areas of the brain. Mapping the cerebellum will be an interesting new frontier for scientific advancement and further understanding of the human body.

Expectations And Realities Of Python Lists And Dictionaries

Have you ever got stumped when you tried assessing an item in a list or dictionary because you received a result which you never expected? Some would say they found a bug. Truly, that bug rests in the fact that you did not understand the subtleties between types when using a list or dictionary.

Take this little program that shows the subtleties in accessing items in a dictionary.

The dictionary has three items, with the keys being ints and the values as strings. That is the first difference you should notice. This is just illustrative because keys of dictionaries can also be any immutable type. On line 3, I asked the interpreter to tell me if 10, int type, was a key, and if ‘10’, string type, was a key. It says True for the former and False for the latter. This is a problem I encounter while teaching on a daily basis. Many persons tend to confuse the int for the string and vice versa. They are different values.

Then comes accessing the items in the dictionary. On line four, I inserted 10 as the key to the dictionary. Note this: as key and not the index. Python reported the string, ten, as I expected. But notice what happens on the line 5 when I used the string ‘10’ as the index. Python gave a KeyError.

So, this shows that types really matters when you are accessing dictionaries. The same goes for lists.

How to find items in a list and dictionary.

Imagine we have a list of names.

When you run it, you should notice that the int 1 is not in the list. I could have used some other value, maybe ‘one’ or maybe ‘Rose’ but the "in" operator shows us whatever is in the list. One problem I have encountered with most of my students is that they don’t understand the subtleties of the in operator. What I always tell them is to consider it as going through each item in the list and looking for a match. If it returns a match, it returns True, and if not it returns False.

Now, what if we mistake an int for a string or vice versa in the list. Let’s take another list. This time of years.

If you run it, what it prints out is:

2019 in list.
2019 is not in list.

What is going on? It’s just simple. The items in the list are strings but on line 10 we gave it an int. So, when programming you have to be very careful not to be carried away and confuse an int for a string and vice versa.

What about indexing and keys.

What we expect is that when we give the interpreter something like variable_name[index] when it is an iterable, we should expect to get an item in return. But what item we get depends on the data structure we are using. If variable_name is a list, we will get an item in the list with that index. But if variable_name is a dictionary, what we get is a value of the key, index.

That gets many people confused sometimes. Well, it is all about knowing that lists and dictionaries are arranged differently. A list contains references to items of value and each item is indexed from zero. For example, let’s take our list of names again.

names = ['david', 'michael', 'daniel']

The list has three items which are referenced through an index. 'david' is at index 0, 'michael' is at index 1, and 'daniel' is at index 2. So, we can access the items through the indices. For example this command, names[0] will return david, while names[2] will return daniel.

But this is different with dictionaries. Let’s take a dictionary of ints as keys and strings as values for example.

num_dict = {10 : 'ten', 20 : 'twenty', 30 : 'thirty'}

If we run the statement num_dict[0] we will get a KeyError. You know why? Because dictionaries accesses its values based on the keys and 0 is not a key in the num_dict dictionary. So, don’t confuse this with that of lists. To access the second item in the dictionary which is ‘twenty’, we need to get it through its key, and the key is an int, 20. So we run the statement thus: num_dict[20] which returns ‘twenty’.

Note that keys of dictionaries can only be immutable types, including sets, while values for dictionaries can be of any type.

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