SP 133_L2_Cortical And Subcortical Structures

Lex took the jeep home to school one day. When both her and another student handed over their fare, the driver asked them, “San baba nito?”. Both Lex and the other student replied “Sa La Salle po.” and “Sa school po.” respectively. What cortical structure of the brain allowed then to understand the driver and reply accordingly?

Wernicke’s Area or BA 22, located in the temporal lobe.

Gelo wants to encourage his classmates in their next LE by evoking the statement, “Never back down never what?” What structure in the basal ganglia helps his brain plan and select the necessary motor routines needed by his speech muscles needed to produce said statement?

The Striatum, particularly the Caudate Nucleus

During a lecture demonstrating speech acoustics, Alia was told by the teacher to sing. What functional structures in the basal ganglia helped her achieve the task she was directed to do while preventing any involuntary movement—say for example randomly beat-boxing—from happening?

For production of voluntary movement:

• Striatum (Putamen and Caudate Nucleus)

  • directly tells the GPi and Substantia Nigra to stop telling the thalamus to stop working, thalamus keeps on sending the excitatory signals for the body to work

For inhibition of unwanted movement:

• Subthalamic Nucleus

  • sends excitatory signals to the GPi and Substantia Nigra, which tells the thalamus to stop working

Identify the pathway of signals from the brain to our muscles during speech production.

Limbic System —> Prefrontal Cortex —> Broca’s Area (BA 44, 45) —> Supplementary Motor Area (BA 6) —> Primary Motor Cortex (BA 4)

Differentiate the roles of dorsal and ventral pathways in speech

Dorsal

• Pathway 1 (BA 22 to 6) - auditory-motor integration

• Pathway 2 (Wernicke’s to Broca’s, BA 22 to BA 44) - storage of speech acoustics, comparison of one’s utterance with those properly pronounced.

Ventral

• Both pathways attach meanings to sound and sound combinations

  • Pathway 1 - Superior Temporal Gyrus (PAC: BA 41, 42) to Broca’s (BA 45)

  • Pathway 2 - Anterior-superior temporal gyrus to frontal operculum

What are the three types of sensation according to Charles Scherrington’s scheme? 

• Exteroreceptors

  • Mediates sounds, sights, smell, and cutaneous sensations

• Proprioceptors

  • Mediates deep somatic sensations from receptors that are beneath your skin

• Interoceptors

  • Responsible for sensation for visceral pain, pressure and distensions

TRUE OR FALSE

One body part strictly corresponds to being innervated by one cranial nerve.

FALSE

Body structures and cranial nerves are not a 1:1 correspondence.

Example: Facial structures are being innervated by two cranial nerves - V and VII, which corresponds to different functions

Which is the lesser importance pathway in human neurology?

a) Spinocerebellar Pathway

b) Dorsal root Pathway

c) Proprioceptive Pathways

a) Spinocerebellar Pathway

because there is usually poor localizing information available  about these tracts.

Why is it important to have a vibratory sensation when speaking?

It is important to have vibratory sensation when speaking because some speech sounds use vibration

Example: speech sound of /b/ uses a vibratory component to it: larynx or vocal folds need to vibrate in order to produce the speech sounds, thus it is necessary to feel that vibrations to produce speech sounds correctly.

TRUE OR FALSE

Somatic sensations will travel through the lateral spinothalamic tract and the anterior spinothalamic tract

TRUE

In exteroreceptors tract, somatic sensations will travel through the lateral spinothalamic tract and the anterior spinothalamic tract 

Why is speed more vital than force in speaking? What happens if we do not have speed for speaking?

Ans: It is important for speaking that we go through motions quickly because speech is fast. At the same time, if speed is absent in our articulators, we will tend to speak very slowly.

Which is not necessarily involved in the actual movement but in the preparation to do the movement?

Ans: Premotor Area / Premotor Cortex

What happens in a phonemic difference?

Ans: When a phone changes, the meaning of the word also changes.

Which of the following is true:

1. The corticospinal tract handles the lungs and is the major pathway for all movement of the trunk and limb

2. The corticospinal tract is a voluntary pathway for all speech muscles except for respiration

3. The corticonuclear tract has many ipsilateral innervation.

4. The corticonuclear tract and corticospinal tract separate at the lower brainstem level

Ans: 1 and 3

For 2: the CORTICONUCLEAR TRACT is a voluntary pathway for all speech muscles except for respiration.

For 4: they separate at the UPPER brainstem level

Select the correct pathway:

1. Somatosensory Cortices → Premotor Area → (Broca’s Area) → Supplementary Motor Area → Primary Motor Cortex → 

Corticonuclear Tract → UMN → LMN → Muscle Contraction

Corticospinal Tract → UMN → LMN → Muscle Contraction

2. Somatosensory Cortices → (Broca’s Area) → Premotor Area → Supplementary Motor Area → Primary Motor Cortex → 

Corticonuclear Tract → UMN → LMN → Muscle Contraction

Corticospinal Tract → UMN → LMN → Muscle Contraction

3. Somatosensory Cortices → (Broca’s Area) → Primary Motor Cortex → Supplementary Motor Area → Premotor Area →

Corticonuclear Tract → UMN → LMN → Muscle Contraction

Corticospinal Tract → UMN → LMN → Muscle Contraction

4. Somatosensory Cortices → Premotor Area → Supplementary Motor Area → (Broca’s Area) → Primary Motor Cortex → 

Corticonuclear Tract → UMN → LMN → Muscle Contraction

Corticospinal Tract → UMN → LMN → Muscle Contraction

Ans: 2

Liam is trying to make the sound “a”. However, the corners of his lips keep on twitching uncontrollably, making his articulation of the sound imprecise. Which pathway of the basal ganglia is affected?

Indirect pathway: it inhibits unnecessary movement

Which of the following is not a function of the cerebellum?

a. initiation of a desired movement

b. coordination of voluntary motor activity

c. motor learning

d. motor memory mechanisms

a. initiation of a desired movement

this is a function of the basal ganglia

This theory is used for error-sensing of negative feedback to correct the performance of speech production structures.

Servomechanism Theory

Alex wanted to say the word “make”, but she said “nake” instead. Her auditory system received the information and delivered it to the brain where it was processed and recognized as an error. Alex then tried to correct herself by repeating the word “make”.

What type of loop system did Alex use?

Closed loop system

TRUE OR FALSE

When trying to read out a loud a word that we have encountered for the first time, we are using both closed loop system and open loop system to regulate speech.

FALSE

The open loop system is dependent on the information from prior experiences. Since it is a new word, we have no information about the correct pronunciation of the word.