Eric R. Kandel 1955
Sigmund Frued:
New structual theory of mind 1923-1933
Distinction between the conscious and unconscious mental functions
Mentals functions were dictated by three interacting psychic agencies: The ego, the id and the superego
At the surface of the mental apparatus is the consciousness; Beneath the surface is unconscious.
Conscious component recieves the sensory information and interacts with the outside world, whereas the unconscious components act through repression and other defenses to inhibit the instinctual urges of the id
Basically, the preconscious interacts with the real world while the unconscious manages the instictive urges of our id.
The superego is the carrier of our moral values
Ego has 2 components:
- Conscious
- Unconscious
Operates logically and guides its actions by the reality principle.
id is the unconcscious component of the ego which is driven by hedonistic principles. It is also the only mental structure present at birth.
The super ego also operates unconsciously, specifically it embodies our morals and aspirations
It is unknown where the ego, id and the superego reside.
Pschyoanalysis must be studied one nerve cell at a time - Grundfest
Frued's careers and the heirarchical nature of this study
Frued began his own career and solved hidden riddle one nerve cell at a time. He began studying single nerve vells and anticipated a key point of what later came to be called the neuron doctrine. From there he practices his discipline by treating mentally ill parents in Vienna.
Kendel was attempting this journey in reverse: Starting from the structural theory of the mind to the signaling elements of the nervous system.
Consciousness
Psychology's biggest question:
What is the nature of consciousness and how does it affect various psychological processes that influence the conscious thought
How do the conscious and the unconscious processes differ in their representation in the brain?
Consciousnes is selection writ large. It is the awareness of the self. It is our ability to experience pleasure and pain and attend to and reflect upon those experiences. Conscious attention allows us to shut our extraneious experiences and focus on the critical events that confront us.
Francis Crick, a creative and influential biologists of the latter half of the 1900s wanted to study the nature of consciousness
Evolution of perspective on Consciousness
Consciousness was first mentioned in the 5th century by Plato and Hippocrates. Plato thought the sould is immaterial, while Hippo thought the soul is formed by biological processes and thus tangible.
Rene descartes , one of the 17th centuries, viivid minds described the soul and body as the two components of human nature.The soul was thought of as the intangible, indepdent, immortal component that rests within the tangible, material, perishable body. This school of thought of dualism thrived in the 18th, 19th and 20th centuries and garnered attention from scientists like Franics Crick.
Crick said its inaccessible thereby it cannot be studied scientifically.
Karl Popper, the Vienna-born philosopher of science, and John Eccles agreed the soul is immortal and independent of the brain.
Some philosophers like Dnaiel Dennet suggested that consciousness is not a distinct, higher-order operation ofthe brain; rahter it is hte combined result of the computationals workings of the higher-order areas of the brain that is concerned with the later stages of information processing. ⭐
Searle and Nagel suggested conscious was both unified and subjectified.
Experiences come to us as a unified whole, which means that all of the sensory data we absord is melded into and single, coherent, conscious experience.
In a surgical patient whose brain is severed between the two hemispheres, there are two conscious minds, each with its own unified precept.
Subjectivity means that each of us experiences private andunique sesations that much more real to US than the experiences of others.
We can only know and appreciate their experiences if its is shared with us.
Experiences and the significance they hold for an individual are subjective. For example, musical notes are just physical sounds that emit from an instrument, but the our brain reconstructs our perception of the object. Till now we do not know who the electrical activity in ourneurons give rise to the meaning we ascibe to object we percieve.
The fact that conscious experience is unique to each person raises hte question of whether it is possible to determine objectivley any characterising
As yet, we do not know how the firing of specific neurons leads the subjective component of conscious perception. We lack adequate theory of how an obejctive phenomemon, like musical notes, cause electrical signals in the brain, can cause subjective experiences, such as joy.
To uncover the explanation behind subjective experiences science has to significantly change its methodology
Subjective properties arise from the properties of ibjects (interconnected nerve cells). Science cannot tell us yet WWWH of these subjective proerties
Step 1: Reduce something subjective to something physical and objectivve.
Physical location of consciousness
Gerald Edelman, a leading theoretician ont eh brain and consciousness assets that it is unlikely that we will be able to find the consciousness through a simple set of neural correlates.
Crick and Koch on the other hand believe that they until of consicousness will have direct neural corerlated because they most liekly incolce a specific set of neurons with specific molecular signatures.
In that case, the intial task is to locate where within the brain that small set of neurons and neural activity exists
Cricka nd Koch focues on a sheet of brain tissue below the cerebral cortex they they believe mediates the unity of experience. It can connect to and exchange informationw ith almost all of hte sensory and motor regions of hte cortex as well as the amygdala, which plays an important roles in emotion.
Using MRA, Eric Lumer and his team at UCL identifies the frontal and parietal areas of hte cortex as the regions of hte brain that become active when a person's conscious attention switches fromo ne image to another.
The prefrontal and posterior parietal regions determine which image to enhance int eh visual system, which then brings the image into consciousness and unifies the image presented to conscious awareness by each eye.
How is visual perception endowed ith emotion
Kendel and Amit Etkin a PHD student and Joy Hirsch a brain imager at Columbia researched how normal people respond consciously and unconsciously to pictures.
The conscious stimuli and unconscius timuli affect different regions of the amygdala, and they did so to differing degrees in different people, depending ont their baseline anxiety.
A person's background axiety affected their unconsciousperception of fearful faces: The higher the measure of background anxiety, the greater the person's response.
Conscious perception of fearful faces activated other parts of the brain regardless of a person's background anxiety. The parts of the brains that unconsiously percieved threats were only activated for the anxious volunteers.
In summary, unconsciously percieved threats disproportionalely affect people with high background anxiety, whereas consciously percieved threats activate the fight-or-flight response in all volunteers.
There is always conscious and unconsious awareness of a stimulus. Unconscious emotion can intensify responses to stimulus. They suggest that the effects of emotions like anxiety are exerted most dramatically in the brain when the stimulus is left to the imagination rahter than when it is percieved consciously. Once the image of a frightened face is confronted consciously, evena nxious people can accurately appraise whether it turly poses a threat.
Readiness potential
200ms before the acitonis executed
free wil really exists?
Biological marker
Brain is automatic, but people are free. One cannot infer the sum toal of neural activity simply by looking at a few neural circuits in our brain