Somatosensory Cortex and Homunculus

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of the somatosensory cortex in the brain?

To regulate emotional responses to pain

To control voluntary muscle movements

To process visual information from the eyes

To interpret sensory information from the body (correct)

What is the term for the cognitive awareness of one's body in space?

Thermoception

Nociception

Proprioception (correct)

Kinaesthesia

What type of receptors are sensitive to both heat and pain?

Thermoreceptors

Nociceptors

TrypV1 receptors (correct)

Mechanoreceptors

What is the purpose of stimulating different parts of the cortex during neurosurgery?

To map the topological representation of the body Signup and view all the answers

What is the term for the sensation of pain?

Nociception Signup and view all the answers

What type of sensors are found in muscles and provide information about stretching and contraction?

Proprioceptors Signup and view all the answers

What is the primary purpose of the shadowing task in understanding selective attention?

To identify the mechanisms that filter out irrelevant information Signup and view all the answers

What is the main issue with Broadbent's Early Selection Theory?

It fails to explain how we can identify our own name in the unattended ear Signup and view all the answers

What is the main difference between Deutch and Deutch's Late Selection Theory and Broadbent's Early Selection Theory?

The location of the selective filter in the processing stream Signup and view all the answers

What is the function of the attenuator in Treisman's Attenuation Theory?

To weaken but not eliminate input from the unattended ear Signup and view all the answers

What is the primary advantage of Treisman's Attenuation Theory over Broadbent's Early Selection Theory?

It is more consistent with the idea of limited attentional resources Signup and view all the answers

What is the main reason why Deutch and Deutch's Late Selection Theory may seem inefficient?

It assigns meaning to all information before selecting what to attend to Signup and view all the answers

What is the primary purpose of deliberately making brain lesions in animals?

To observe changes in the animal's behavior Signup and view all the answers

Which type of lesion is used to destroy tissue on the surface and deep inside the brain?

Radiofrequency lesion Signup and view all the answers

What is the advantage of cortical cooling compared to other lesion techniques?

It is a temporary and reversible technique Signup and view all the answers

What is the primary limitation of EEG in studying brain activity?

It can only measure the sum total of brain activity Signup and view all the answers

What is the purpose of using kainic acid in lesion studies?

To cause an influx of calcium that kills neurons Signup and view all the answers

What is the advantage of MEG compared to EEG?

It has a better resolution Signup and view all the answers

What is the primary function of the reticular activating system in response to stress?

To control arousal and alertness levels Signup and view all the answers

Which hormone is strongly linked to estrogen and plays a key role in the tend and befriend response to stress?

Oxytocin Signup and view all the answers

What is the result of the body's resistance to stress if not followed by recovery?

Tissue damage and susceptibility to illness Signup and view all the answers

Which stage of the general adaptation syndrome is characterized by the body's initial response to stress, including an increased heart rate?

Alarm Signup and view all the answers

What is the effect of chronic stress on blood vessels?

They distend and become more rigid Signup and view all the answers

What is the primary function of the sympathetic nervous system in response to stress?

To increase heart rate and respiration and prepare the body for 'fight or flight' Signup and view all the answers

Which defence mechanism involves transforming unwanted impulses into something less harmful?

Sublimation Signup and view all the answers

What is the term for the process of attributing one's own feelings of inadequacy to another person?

Projection Signup and view all the answers

According to the psychosexual development theory, what is the result of fixation at a particular stage?

Lifelong conflicts Signup and view all the answers

Which part of the mind is responsible for seeking long-term gratification and is involved in our perceptions and judgements?

Ego Signup and view all the answers

What is the term for the natural energy source that fuels the mechanisms of the mind?

Libido Signup and view all the answers

At what age does the superego typically develop?

Around 4 years old Signup and view all the answers

Study Notes

Somatosensory Homunculus

The brain has a map of the body, located in the sensory cortex, which receives information from the body
Neurosurgeons can stimulate different parts of the cortex to identify what part of the body is affected by a brain tumor
This process creates a topological map of the body in the cortex

Proprioception and Kinaesthesia

Proprioception is the sense of balance and position, reliant on tiny sensors in muscles that send signals to the spinal cord and brain
Kinaesthesia is the sense of movement of the body, not including sense of balance
Proprioception is cognitive awareness of the body in space, while kinaesthesia is more behavioral

Pain and Temperature

Pain is known as nociception, and temperature is thermoception
The TrypV1 receptor is responsible for sensing temperature and is also sensitive to pain
Heat causes a conformational change in the protein, allowing for temperature sensing

Responding to Stress

The autonomic nervous system (ANS) works with the limbic system and reticular activating system to allow us to experience and understand emotions
The reticular activating system controls arousal and alertness levels
Stressors trigger the fight or flight system, increasing heart rate and respiration, and releasing epinephrine and norepinephrine
The tend and befriend response is a stress response that involves social support, powered by oxytocin
There are three stages of stress: alarm, resistance, and exhaustion

Physical Effects of Stress

Chronic stress can damage heart tissue, increasing blood pressure and making blood vessels more rigid
Inattentional blindness and change blindness can occur when attention is focused elsewhere

Theories of Selective Attention

Broadbent's Early Selection Theory: all information goes into a sensory register, then a selective filter, and finally perceptual processes
Deutsch & Deutsch's Late Selection Theory: a selective filter is placed after perceptual processes
Treisman's Attenuation Theory: an attenuator weakens but doesn't eliminate input from unattended channels

Lesion Studies and Experimental Ablation

Lesion studies involve deliberately making brain lesions to observe changes in behavior
Techniques include surgical removal, surgical aspiration, nerve cuts, radiofrequency lesions, and neurochemical lesions
Cortical cooling is a reversible and temporary technique

Modern Ways of Studying the Brain

CAT scans (CT scans) and MRI are used to study brain structure
EEG and MEG (SQUID) are used to study brain activity
Cortical cooling is a reversible and temporary technique

Psychoanalysis

Sigmund Freud's theory involves the concept of libido, or natural energy that fuels the mind
Fixation at various stages of psychosexual development can lead to lifelong conflicts
The mind consists of the conscious, unconscious, and id, ego, and superego

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the concept of the somatosensory cortex, which is a part of the brain that maps the body, and the homunculus, a representation of the body within the brain. It also touches on how neurosurgeons can stimulate different parts of the cortex to identify brain tumor locations. Test your understanding of this complex topic!