NE202 Final

EEG/ERP

• low spatial resolution

• Has very good temporal res

• correlational

• non invasive (electrodes on scalp)

ECOG

• better spatial res than eeg but not as good as fMRI

• very good temporal res

• correlational

• Invasive (electrodes on brain’s surface)

fMRI

• excellent spatial res

• poor temporal res

• correlational

• non-invasive (magnetic waves)

TMS

• good spatial res

• poor temporal res

• causal

• non-invasive ; on the scalp

VLSM

• good spatial res

• poor temporal res

• correlational

• Non-invasive ; image based analysis

structural MRI

• excellent spatial res

• no temporal resolution

• detailed images of brain structure

• non-invasive

DTI/DWI

• excellent spatial resolution

• poor temporal resolution

• structural changes and abnormalities in white matter

• correlational

• non-invasive

PET

• moderate spatial res

• slow temporal res

• analyze neurotransmitter release, receptor binding, and blood flow

• correlational

• non-invasive

MEG

• poor spatial res

• excellent temporal res

• images neuromagnetic signals

• correlational

• non-invasive

Patient HM

• Severe deficits in acquiring new declarative memories

• Working memory intact

• retrograde amnesia of ~10 years prior to surgery

• Bilateral medial temporal lobe lesions

• Bilateral hippocampus and other parts of medial temp. lobe removal to treat epilepsy

• couldn’t transfer information from STM to LTM

Patient RB

• confirmed role of hippocampus in anterograde amnesia

• Ischemic event during surgery

• Lesions to CA1 pyramidal cells in hippocampus

• anterograde amnesia and retrograde of 1-2 years

Patient KF

• left lateral parietal lobe lesion

• able to form new declarative memories

• severe deficits in holding words in working memory

• deficit in phonological loop

Patient KC

• Extensive brain damage : Med. Temp. Lobes, dlPFC, Occipital, Parietal

• Retrograde amnesia (episodic lost, but retained semantic)

• Anterograde amnesia (but could learn semantic at a slower rate)

Clive Wearing

• herpes simplex encephalitis

• damage to bilateral hippocampus , inferior frontal and temporal lobes

• procedural memory intact

• few declarative memories beyond the 1960’s

• Some semantic memories remain, few episodic memories

• emotional memories remain

Sensory and Motor Map representations

Brain-Computer Interface

• relies heavily on external computers

• Utilized by patients with little/no motor output, deaf or blind individuals

• wireless implanted electrodes, alternate to sharp electrodes

Population Vector Coding

the combination of multiple cells preferred directions; if there is a match between the preferred direction, the cell will fire strongly. If the match between the movement and preferred direction is poor, the cell will fire weakly or even be inhibited

Cochlear Implants

• captures sound waves from the environment

• processed into digital signals

• electrodes are inserted into the cochlea, bypassing damaged or non-functioning hair cells

• auditory nerve fibers stimulated directly

Functional Roles of Amygdala

• emotion processing- primarily fear

• important in fear conditioning

• forms and stores emotional memories

• processes social cues, recognizes facial expressions, and regulates social interactions

• initiates physiological response to stress

• aids in risk assessment and emotional evaluation of potential outcomes

Functional Roles of Anterior Cingulate Cortex

• detects conflicts between competing thoughts, actions, or stimuli and adjusts behavior accordingly

• evaluates emotional stimuli, modulates emotional arousal, and regulates emotional expression; dysfunction can lead to mood disorders like anxiety or depression

• plays a role in the emotional and cognitive aspects of pain regulation

• evaluates the value of rewards, guides decision making related to reward seeking behavior

• plays a role in theory of mind, empathy, social decision-making and moral reasoning

• involved in error monitoring during movement

Flashbulb memories

a very vivid memory of a powerful event. episodic and very detailed. Is evidence that emotional content is important for memory.

Deep brain Stimulation

• major application in Parkinson’s

• causal

• Better spatial res

• Invasive

Parkinsons Disease

• Loss of dopaminergic neurons in the substantia nigra

• Characterized by hypokinesia and bradykinesia

• Hypoactivity of direct pathway

• Little movement initiation

• Hyperactivity of indirect pathway

• Too much movement inhibition

Huntingtons Disease

• Genetic neurodegenerative disease caused by a CAG expansion in the huntington (HTT) gene

• Striatal neuron (caudate/putamen) loss affects indirect pathway

• Decreased inhibition of GPe eventually leads to increased activity of the thalamus

• Characterized by hyperkinesia

• Movement activation = too much movement

Basal Ganglia Structures

• caudate nucleus

• putamen

• globus pallidus

• subthalamic nucleus

• substantia nigra

Chomskys view of language

• language is standard equipment in humans

• Innately guided learning; children will gain language skills unless prevented by extreme circumstances

• mental grammar exists

Language network

• broca’s area

• wernicke’s area

• arcuate fasciculus

• primary auditory cortex

• angular gyrus

• supramarginal gyrus

• inferior frontal gyrus

• posterior superior temporal gyrus

Default mode network

group of brain structures active when the brain is at rest

• mPFC

• posterior cingulate

• precuneus

• lateral temporal cortex

• inferior parietal lobe

• hippocampus

• parahippocampal cortex

• dmPFC

Brodmann Areas

a system of mapping the cerebral cortex based on cytoarchitectural differences in structure.

Sulcus

a groove in the brain surface

Gyrus

a ridge in the brain surface

Fissure

a deep groove that divides the brain into lobes

Primary sensory cortex location

the parietal lobe, in the postcentral gyrus

Primary motor cortex location

the frontal lobe, in the precentral gyrus

Face processing network

• fusiform face area

• occipital face area

• superior temporal sulcus

• anterior temporal lobe

• PFC

• amygdala

• posterior superior temporal sulcus

Double dissociation

• 2 or 3 groups

• Patients with NP1, patients with NP2, and normal controls

• 2 tasks

• People with different kinds of neuropathologies exhibit opposite patterns of deficits 

Biological Motion perception

the ability to perceive and interpret movements and actions based on visual cues. The superior temporal sulcus is crucial in processing, along with the mirror neuron system.

Theory of Mind

• The cognitive abilities to represent the information in the mind of others, distinguishing them from what we know

• Being able to understand that others have thoughts different from one’s own

Block design fMRI

• stimuli presented in continuous periods of time, each typically consists of a single condition or task

• analyzed by comparing the average during the task to baseline periods

• suitable for detecting robust and sustained activations related to specific tasks or conditions

• higher statistical power

Event related fMRI

• stimuli/events are presented in randomized order

• analyzed by modeling the hemodynamic response to each event separately

• useful for studying transient or brief

Brain structures involved in episodic memory

• hippocampus

• Medial Temporal lobe

• PFC

• amygdala

Brain structures for working memory

• PFC (dlPFC, vlPFC, vmPFC)

• Posterior parietal cortex

• dorsal lateral geniculate nucleus

• inferior temporal cortex

• basal ganglia

• hippocampus

• anterior cingulate

Baddeley model

describes working memory as a system with 3 components: central executive, the phonological loop, and the visuospatial sketchpad.

Double dissociation for STM and LTM

refers to the phenomenon in which impairment to one type of memory has little to no effect on the other type

retrograde amnesia

loss of memories from the past

anterograde amnesia

inability to create new memories

Hebb’s rule

states that when two neurons are repeatedly active at the same time, the connection between them strengthens. This principle underlies how neurons form associations and memories in the brain, helping us learn and remember by reinforcing connections between neurons that are frequently activated together.

semantic dementia

neurodegenerative disorder characterized by the loss of semantic memory (ability to understand and recall the meaning of words, concepts, and knowledge of the world). Often associated with temporal lobe damage

alzheimer’s disease

• degenerative memory loss

• damage is diffuse and wide spread in the brain

• medial temporal lobes degenerate early

mild cognitive impairment

• memory and cognitive impairments, but able to lead a normal life

• a precursor to dementia/alzheimers

• MRI and PET scans can reveal it

cognitive maps

mental representations or internal models of physical spaces, environments, or spatial relationships. They allow individuals to navigate, orient themselves, and understand the layout of spaces without direct sensory input.

grid cells

• found in the entorhinal cortex

• fire in a hexagonal formation

• play a role in path integration, updating an organism's position based on self-motion cues, and creating a spatially organized representation of the environment.

relational memory theory

proposes that memory is not just about storing isolated facts or items but also about encoding and retrieving the relationships and connections between these items.

simple model of episodic memory

encoding —> storage —> retrieval —> autonoetic consciousness —> reconstructive nature

subsequent memory task

a research methodology used in cognitive neuroscience and psychology to investigate the neural processes and brain mechanisms underlying memory encoding. It involves presenting participants with stimuli (such as words, images, or videos) and then assessing their memory for those stimuli at a later time.

Dorsal attentional control system

• endogenous attention

• supports attentional focus - maintains attention

• intraparietal sulcus, superior parietal lobe, frontal eye fields

Ventral attentional control system

• exogenous system

• alerts to salient stimuli outside of attentional focus

• disengages from current attentional focus and reorients

Endogenous attention

• voluntary

• directed by mind, not stimuli

• highly focused

Exogenous attention

• reflexive

• comes from outside of mind

• alerts us to important changes in the world

Spatial neglect

• neglect of left side of space

• occurs across sensory modalities

• RH damage to frontal and parietal lobes

• deficit in attention not perception

Phrenology

pseudoscience popular in the 19th century that proposed a relation to shape and size of bumps or contours in the skull and mental faculties or personality traits

Implicit memory

the use of stored knowledge without awareness of its use or effort in recollection (assisted by previous experience).

premotor theory of attention

• Suggests that shifts of attention and preparation of goal-directed actions are closely linked

• Suggests that a covert shift of attention is similar to a saccadic eye movement, but without the eye movement

capacity limits in attention

The focus is regarded as having a limited capacity and holds up to four of the activated representations.

N400

• semantic anomalies

• Perception of Anomalous words yields a Negative response 400ms after word begins

LAN

ERP response to Syntactic Violations

P600

ERP response for Syntactic Anomalies

Dual system of cognition

Hot and cold system

Saliency Map

• a theoretical idea for predicting direction of eye movements and attention

• Some parts of an image attract attention more effectively than others.

• a bottom-up map of the relative interest of scene regions. Neural locus: Superior Colliculus, Pulvinar

Priority Map

Where we choose to move our eyes or covertly direct our attention depends on: stimulus saliency, our goals/values, where we have already looked

Intraparietal sulcus

Change Blindness

Exogenous Distractors Mask Other Exogenous Cues

To see an object change we must attend to it!

Inattentional Blindness

Salient stimuli can go undetected

Highly focused (endogenous) attention blocks out other salient (exogenous) stimuli

Go signal

the neural signal that initiates and coordinates voluntary movements. Typically originates in the primary motor cortex or the supplementary motor area

Mirror Neurons

Important in empathy; fire in response to watching someone else do something, as well as doing it yourself

Split brain surgery

severing of the corpus callosum to treat severe epilepsy.

Barlows neuron doctrine

• neurons are information processing units

• Sparse coding- neurons in the brain are selectively responsive to specific features

• the brain reduces redundancy in neural activity

• neural representations in the brain are optimized for efficiency

• neural plasticity

Marr’s 3 levels of explanation

computational - what

algorithmic - how

Implementation - hardware/neurological

Phineas Gage

• Damage to Left OrbitoFrontal Cortex & Medial PFC

• Had trouble interacting with others

• Behaved unethically

Belmont Report

guidelines for conducting ethical research on human subjects

respect for persons, beneficence, and justice

Causal Research methods

research for investigating the cause-and-effect relationship between variables

Correlational research methods

seeks to identify patterns and connections between variables

Ventral-Dorsal

“stomach”-”back”

Anterior-Posterior

front - behind

Medial-Lateral

close to center- away from center

Rostral-Caudal

front of head - back of head

Ventral Striatum

• involved in reward processing

• involved in motivation and goal-directed behavior

• involved in learning associations between stimuli and rewards

• contributes to emotional processing

• dysfunction leads to addiction and impulsive behaviors

Implicit Bias

An unconscious attribution of particular qualities (stereotypes) to a member of certain social group

Implicit Associations Test

Caucasian vs. African American Faces

Positive or Negative words / traits

Logic is similar to Stroop Test (RT differences)

RH temporal parietal junction

• theory of mind

• social cognition (empathy, moral reasoning, social decision making, social judgements)

• self-other distinction

• attention and salience detection

Orbitofrontal damage

• impaired decision making

• social and emotional dysfunctions

• risky behavior

• social inhibition and disinhibition

• personality changes

• executive functioning deficits

PTSD

Extinction is impaired. Even when a stimulus no longer predicts a shock, it still yields a response; in skin responses, amygdala, and and vmPFC.

Inhibitory control of action

• PFC (dlPFC)

• Anterior cingulate

• Inferior frontal gyrus

• Basal ganglia

• SMA

• Frontoparietal network

• Thalamus

• brainstem

Stroop effect

Color naming task where word reading is automatic but color naming is more novel/less practiced