Behavioral Neuroscience Exam 3

Cognitive Control

The ability to regulate cognitive processes to achieve goals, involving functions like attention, working memory, and decision-making. - Controlled by the Prefrontal Cortex

Core Executive Function

Inhibitory Control

Working Memory

Cognitive Flexibility

Higher order (built from above)

Organization of Frontal Cortex

Believed to be hierarchically organized from anterior to posterior

Anterior of frontal cortex

abstract goals

Posterior parts of Prefrontal Cortex

Concrete goals and direct actions

Dorsal organization of Prefrontal cortex

Where (how pathways)

Ventral Pathways of Prefrontal Cortex

What pathways

Medial Pathways of Prefrontal Cortex

Hot or value related processes

Lateral prefrontal cortex organization

Cold or cognitive processes

How Does the prefrontal Cortex implement cognitive control

-integrates information from sensory, motor, and other cortical areas

-Subcortical areas in learning and reward

-Guides information flow through the brain through top-down processing and selecting specific action plans

Phonological Working Memory

-able to hold information and generate auditory info for about 2 seconds when rehearsed

-speech/acoustic store and subvocal articulatory rehersal process

Functions of Phonological Working Memory

Facilitating language Acquisition

Control behavior through self-instruction

Visuo-spatial working memory (Sketchpad)

-Holds limited amount of visual info. while you attend to it

-survives eye movements, blinks, and other visual interruptions

Functions of Visuo-Spatial Working Mem.

Maintaining continuity across eye movements

creating and maintaining images when imaging and describing an object or scene

Model for working memory

The central executive functioning area works by both providing information and gaining information from the phonological loop and visuospatial sketchpad

Networks in Visuo-Spatial Memory

Prefrontal Cortex

Posterior Parietal Cortex

Visual cortex and inferior temporal cortex

Prefrontal Cortex in Visuospatial Memory

-May not be directly representative of visual content

-top-down influence over representations in visual cortex

-control what visual info is represented in the working memory

Posterior Parietal Cortex in Visuo-Spatial Memory

-May provide top-down signals

-may represent depending on info withint he working memory

Visual Cort4ex and Inferior Temporal Cortex in Visuo-Spatial Memory

represents and stores visual content

Brain Networks of Phonological Memory

-Left hemisphere Bias

Lateral prefrontal cortex (Brodmann area 44)

Premotor motor cortex

Temporo-Parietal junction (Brodmann area 40)

possible auditory cortex

Delayed Response task for working memory on monkeys

monkey is shown and empty and food dish. Slide is then closed and food is covered and then the monkey needs to reach to grab correct dish for food

During this time a sustained AP is fired after seeing food

Shows how brain remembers information of period of time

How does the brain generate Sustained activity for Working memory

Info goes through inputs, hidden layer and delay periods, and then the output

info flows in a loop through feedback connections

Recurrent neural networks (where neurons send feedback signals to each other)

How does the prefrontal cortex respond during delay periods

Different cells respond at varying times depending on their level of response to the stimulus (Ex: some respond to a subset of signals, some are sustained other first after a delay, etc.)

what specific brain area supports the prefrontal cortex in memory and cognitive control?

Mediodorsal thalamus- Allows an excitatory signal to enter which allows an array of delayed responses from neurons which allows sustained activity. This keeps a signal alive through the whole task

Why do we have rules?

rules govern why we have specific actions and guide our behavior

have both exogenous and endogenous cues depending on the context

Some rules are specific and others are more abstract

What happens when our brain is unable to follow rules

lesions in PFC can cause a difficulty to follow rules and these deficits can lead to schizophrenia

Where are abstract rules held in the PFC

anterior part of PFC

Where are concrete rules held in the PFC

posterior PFC

Task Set

Configuration of Cognitive Processes Necessary to Perform a task

Ex: encoding a set of instructions from a researcher through rehersal

What is Set-Shifting

process of selecting between two competing task sets

Task-Cueing Paradigm

cue is shown for a period until target, then pause, then new cue, then all is repeated

Intermittent Cueing Paradigm

No pauses and simply one target is shown until the switch and then a new target is shown

How does the dorsolateral PFC react to task sets

reacts best to spatial forward and spatial backward

How does hte Parietal lobe react to task sets

reacts best to spatial forward and spatial backward will some activity in verbal forward and backward

How does the Ventrolateral PFC react to task sets

most reaction in verbal forward and backward

How does the Temporal Lobe react to task sets

most reaction in verbal forward and backward

How does anterior PFC react to Task sets

general activity in spatial forward and backward along with verbal forward and backward

How does the Anterior Prefrontal Cortex react to specific task sets for the DLPFC (dorsalateral PFC)

Spatial tasks

How does the Anterior Prefrontal Cortex react to specific task sets for the VLPFC (Ventrolateral PFC)

verbal tasks

How are decisions made

accumulate sensory evidence

Transform sensory evidence into a decision variable

Apply decision rule based on criteria

How do neurons decide while way to fire for a moving stimulu

one example: neurons have either right or left preference and a decision variable is caculated by subtracting left from right. Then this gives changes in neural activity on a scale

Behavioral Inhibition

Cancellation of planned or early stage of action

Cognitive Inhibition

overriding of mental process, wholly or partly

What happens when inhibition is unsuccessful

impulse or compulsion

ADHD, drug addictions, schizophrenia- impulsive

OCD and drug addictions- Compulsions

What brain structure is key in the stop-signaling in the brain

Right Inferior Frontal Cortex

When damaged, people become impulsive and unable to stop impulses

What is happening when a healthy brain is trying to inhibit an action

Gamma activity goes wayyyyyy up

Happens quickly to inhibit actions quickly

What is the hyper direct pathway

The cerbral cortex sends an excitatory message to the subthalamic nucleus which sends an excitatory signal to the GP internal segment which sends an inhibatory signal to the thalamus

How does the hyperdirect pathway work in inhibition

reduces activity in thalamus to directly inhibit actions

general intellligence

general ability common to cognitive tasks

Crystallized intellligence (gC)

acquired knowledge about nature of hte world and learned operations

Fluid Intelligence (gF)

ability to solve novel problems independent of acquired knowledge

Where is fluid intellligence located

inferior frontal sulcus, interaparietal sulcus, anterior insula, anterior cingulate cortex

What happens when the fronto-parietal network is damaged

fluid intelligence goes down

Damage outside this network has no affect on fluid intelligence

Why do we need attention

too much info to process at the same time so attention helps us focus on important information

Stimulus Salience

item that significantly differs from neighboring items

Stimulus-driven, “bottom-up” or “exogenous” process

Behavioral goals

specific tasks we need to solve

“top down” or “Endogenous” process

How do goals and salience guide attention

top down factors can override bottom-up factors

can be hard to ignore new items and their sudden appearance

Spatial attention

attention to a particular location

Feature-based attention

attention to a particular stimulus feature

Object-based attention

attention to a particular object

Can spread from cued to uncued locations

Temporal attention

attention over time

Overt attention

attention on what you are fixating on

attention guides your gaze to important info

Covert attention

where you are looking differs from where you are attending

attention directed away from your gaze

Posner cueing task

valid target if it appears at cued location

invalid target if it appears away from cued location

neutral target is there is not prior cue

How does attention improves target detection and reaction time

in valid conditions- highest response rate and fastest reaction time compared to invalid conditions

How does attention affect sensitivty of neurons

as attention increases, sensitivity increases

contrast is not as necessary when higher attention is applied

How does attention modulate the response of sensory neurons to stimuli

responses increases when attention is on the preferred stimuli

decreases when attention on ineffective stimuli

brain networks in frontal and parietal cortex for attention

pronto-parietal network including frontal eye field, supplementary eye field, and posterior parietal cortex

provide feedback for sensory info and what is beh. relevant

What does the posterior parietal cortex do for attention

signals attention priorities

neurons respond best when stimuli are beh. relevant

vice versa for beh. irrelevance

How does feedback from the parietal cortex affect the sensory cortex

parietal cortex increases the response to the sensory cortex

this is done through increases AP sent from the parietal to the sensory cortex

when there are few AP from the posterior parietal cortex leads to reduced activity of sensory neurons

How does the frontal eye field affect the visual cortex

feedback from the frontal eye field increases responses in the visual cortex

When stimulation is appleid to the frontal eye field more V4 cells respond in the visual cortex

What does the pulvinar do

routes information across the cerebral cortex

either directly connected or will be indirectly connected for the cortical areas

How does attention affect pulvinar neurons

Attention increases activity for the pulvinar neurons

What happens with spatial neglect

severe condition where patients are not aware of one side of space

often occurs in right hemi.

commonly due to damage of posterior parietal cortex

Reference frames that can be affected by neglect

egocentric and allocentric

Attention and Eye movement networks overlap in brain

Same fronto-parietal and subcortical areas contribute to attention and eye movement

can be used to direct attention and eye movements

Lateral interaparietal area, Supplementary eye field, frontal eye field

What is Consciousness?

awake state in which we have experiences, we are able to report

mirror self-recognition test

mark placed on forhead and observed if they wipe off mark on own

Sleep

non-REM sleep (stages 1-3)

REM sleep

General anesthesia

caused by drugs with diff. molecular mechanisms of actions

Disorders of consciousness

brainstem death, coma, unresponsive wakefulness syndrome, minimally conscious state

Awake characteristics

low voltage, fast EEG

Vivid, externally generated sensations

logical and progressive thought

Continuous and voluntary movement

often eye movement

Non-REM Sleep

high voltage, slow EEG

Dull or absent sensations

logical and repative thought

occasional involuntary movement

eye movement rare

REM sleep

low voltage, fast EEG

vividing internally grenerated sensations

vivid, illogical, bizarre thoughts. Muscle paralysis, movement commanded but not carried out mov.

Often, rapid eye movement

What are the two components of Consciousness

arousal and awareness

Arousal

alertness or vigilance

Awareness

refers to conscious perception of the richness of conscious experience

Awareness of environment

conscious perception of environment using our senses

Awareness of Self

inner process that does not require our senses or external stimuli; includes knowledge of our own socio-cultural history

Levels of awareness and arousal

different levels of awareness and wakefulness depending on the state

Ex: high in both for conscious wake compared to super low in both for a coma

Neural Correlates for consciousness

minimal neural mechanisms jointly sufficient for consciousness

How is the neural correlates of consciousness connected

large scale intergration across brain areas

frontal cortex; parietal cortex and posterior cingulate, temporal cortex, intralaminar nuclei of thalamus extensively connected with above cortical areas

How are integration happening for the NCC

through neural synchronizationW

What areas do not contribute to the NCC

cerebellum-the lack of integration within this system makes it appear that this brain area is not involved

What areas are important for arousal

brainstem and thalamic areas such as the Mesencephalic reticular formation, Basal nucleus of Meynert, hypothalamus, medial septal nucleus, and THalamic reticular nucleus

Cortical and thalamic areas involved in awareness

Thalamus, occipital cortex, parietal cortex, frontal cortex, and temporal cortex

Global neuronal workspace theory

consciousness depends on an “ignition” process through which info becomes globally available

front down processing is required from the frontal lobe to specialized processing in the posterior cortex

Integrated information Theory

Consciousness depends on integrated information

integration is supported through interactions between neurons in cortical and thalamo-cortical circuits

Predictive Coding (frontal cortex is important)

modeling of consciousness through top down processing

moves from frontal lobe to sensory cortex

Higher order theories (frontal cortex important)

consciousness depends on the frontal cortex, which supports higher-order thoughts about sensory experiences

sensory representations within the posterior cortex alone is insufficient