Psych240 quiz2

cognitive neuroscience

the study of the physiological basis of cognition

Building blocks of the nervous sytem

individual neuron made up of cell body, axon, and dendrites

basic building block of nervous system

individual neuron (lowest level)

Neurons

cells specialized to create, receive and transmit information in nervous system

Nerve Nets

interconnected neurons, continuous communication of signals through neural network. Early idea that was contradicted by Ramon y Cajal’s neuron doctrine.

Dendrites

multiple branches reacting from the cell body, which receive info from other neurons

cell body

performs metabolic mechanisms to keep the cell alive, also integrates incoming information (from dendrites) which determines if the neuron fires

Axon

tube filled with fluid that transmits electrical signals to other neurons

action potential

a neural impulse; a brief electrical charge that travels down an axon then crosses synapse to the dendrites of other neurons

Measuring action potentials

Microelectrodes pick up electrical signal, most are all or nothing

rate of firing

low intensity-slow firing rate
high intensisty-high firing rate

Neuron Doctrine

The idea that individual cells called neurons transmit signals in the nervous system, and that these cells are not continuous with other cells as proposed by nerve net theory.

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

hierarchical processing

processing that occurs in a progression from lower to higher areas of the brain (simple to complex)

specificity coding

representation of specific stimulus by firing very few neurons specialized to just respond to a specific stimulus

sparse coding

when a particular object is represented by a pattern of firing of only a small group of neurons, with the majority remaining silent

population coding

representation of a particular object by the pattern of firing of a large number of neurons

localization of function: language

Language production is impaired by damage to
Broca's area
(Frontal lobe)

Language comprehension is impaired by damage
to Wernicke's area (Temporal lobe)

localization of function: perception

Primary receiving areas for the senses
Occipital lobe: vision
Parietal lobe: touch, temperature, pain
Temporal lobe: hearing, taste, smell

Coordination of information received from all
senses
Frontal lobe

Higher cognitive functions

frontal lobe (prefrontal cortex, orbitofrontal cortex)

lower brain functions

Cerebellum: motor coordination
Brainstem: basic metabolic (breathing, heart, etc.)

single dissociation

a situation in which a patient is impaired on a particular task (task A) but relatively spared on another task (task B)

double dissociation

A situation in which a single dissociation can be demonstrated in one person, and the opposite type of single dissociation can be demonstrated in another person (i.e., Person 1: function A is present; function B is damaged; Person 2: function A is damaged; function B is present).

neural networks

group of neurons or structures that are connected together

What is consciousness?

surprisingly hard to define in "noncircular" manner , possibly what it's like (to experience red, pain,etc)

subjunctive experience/ awareness

\-fundamental meaning -phenomenal consciousness

-1st order awareness

reflective awareness

-thinking about external or internal events
-access consciousness
-2nd order awareness

self-awareness

knowing that our experience is ours, different from others experience

content consciousness

when alert, awake, etc. are we conscious or not?

state consciousness

are we awake, asleep, in a coma, etc.

Distributed Representation

Occurs when a specific cognition activates many areas of the brain.

What is mind/body problem?

the relationship between our experience and what’s happening in our brain.

mind-body problem - aspects

Dualism (Descartes)- mind and body are fundamentally distinct "substances", so they can exist separately idealism (Berkeley)- the mind is a fundamental reality

Materialism/Physicalism- "physical" things are the fundamental reality

Reductive Method

break down into components

problems with physicalism

-How any of it gives rise to consciousness
-No way to explain why (x,y,z) brain function is associated with awareness

scientific approach to consciousness

-essence is the contrastive approach
-seek to identify neural correlates of consciousness
-correlation, not causal

Animal consciousness

-widely accepted
-gallup mirror test (recognize in mirror)

machine consciousness

artificial intelligence

Blindsight

a condition in which a person can respond to a visual stimulus in their "blindspot" without consciously experiencing it

neglect

rare brain damage where patient ignore part of whole drawing

split brain patients

people whose corpus callosum has been surgically severed, seems to yield two separate consciousnesses

Extreme hydrocephalus

-enlargement of ventricles squeezes and destroys brain tissue

Main Effect

occurs when independent variable (what’s manipulated) changes the results of the dependent variable (what’s measured)

Interaction

occurs when one independent variable depends on another independent variable

* ON GRAPH, parallel lines = no interaction , non parallel lines = interaction

Subtractive Method

subtract the detection time from total time of choice task, to find the time it takes to make a decision

Problems with Subtractive Method

Assumption of Pure Insertion, Assumption of additivity, Assumes you already know what the stages are

Chalmers “Hard Problem”

studying the brain does not explain consciousness

Neurotransmitters

Chemical that is released at the synapse in response to incoming action potentials.

**Functional magnetic resonance imaging (fMRI)**

A brain imaging technique that measures how blood flow changes in response to cognitive activity.

Problems with brain imaging

fMRI makes many assumptions and represents time resolution averages