Midterm 1 Flashcards
(70 cards)
Brain Stimulation
- Studying epileptic behaviour
- Stimulating certain areas produces certain behaviours
- Right hem: deja vu, religion, short term mem., faces, line perception
- Left hem: accelerate or block speech
Double Dissociation
- Neuro imaging, case studies
- Neural substrates of brain functions
- right hem lesion impairs function x not y, left hem lesion impairs function y not x
Patients with brain lesions
PG - removal of section of left temporal lobe, intelligence (slightly) and verbal memory (sig) decrease.
SK - removal from right temporal lobe, nonverbal memory recall sig. decrease
Split brain & Comissustory patients
- Due to epileptic seizures, corpus. callosum is separated
- The Interpreter: shown 2 images, asked to select 3rd matching image, each hand chooses an images corresponding the hem that is viewing image
Split Face Test
- pictures of faces are split down the middle and recombined
- When asked which was the original, they would say right side (left hem)
The Watta Test (Sodium Amobarbital Injection)
anesthetize a hem.
-patients cannot speak, move the contralateral arm or see through contralateral eye
Specialization Theories
- Unique functions for each hem.
- Extreme: only one hem. facilitates a given process
- Modern: left hem = collection of focal points, right hem = functions diffusely
Interaction Theories
- Cooperation between hems.
- 1: 2 hems function simultaneously but work of different processing
- 2: hems have capacity to inhibit or suppress the other
- 3: preferentially receive or pay attention to info
What is lateralized?
We do not know, no simple or general answer
Handedness - Environmental
Utility - mothers hold infant with left hand (soothing, freeing other hand)
Reinforcement - children were forced to use right hand (has not increased left handedness)
Damage - genetic bias to right, stress in utero (twins), genetic anomalies
Handedness - Anatomical
Enhanced maturation - left hem has enhanced mat. and development
Nature - heart is on left side, left temporal lobe is larger
Left hem dominant for motor control
Handedness - Hormonal
Testosterone (can be inhibitory on development)
- Acts on left hem, leading to greater development of right hem (left hand)
Handedness - Genetic
Potential dominant gene
Tasks Favouring Women
- Math Calc
- Recall
- Displaced objects
- Precision, fine motor
- Matching
Tasks Favouring Men
- Math Reasoning
- Geometric form
- mental rotation
- target motor skills
- visualizing
Motor Skill Sex Differences
- Men better at target throwing - difference is apparent in 3 yr olds, & chimps
- women have finer motor skills, also appears in children
Spatial Analysis Sex Differences
- Men learn routes in fewer trials
- Women remember more landmarks
Mathematical Sex Differences
- Gap closes as people age (adolescents 4:1)
- Women who are good at math tend to be good at language, not men
Brain Structure Sex Differences
- Production of estrogen
- Prefrontal & Paralympic & parietal cortex (sig. bigger in women)
- Angular gyrus (high vol. of androgen receptors in men
- males have uniform grey matter, women have high and low concentrations
Occipital Lobe - V1 and V2
V1 is heterogeneous
- blobs: colour info
- interblobs: process form & motion perception
V2 is heterogeneous
- thin stripes: colour perception
- thick stripes: process form info
- pale stripes: motion perception
Pathways
Dorsal Stream: visual guidance of movement (parietal pathway)
Ventral Stream: object perception and motion perception
STS Stream: object perception & motion perception
Damage to Occipital Lobe
V1 & V2:
- separate colour, form & motion
- Info from blobs to V1 to V4 for color proc.
- Info from V1 to V5 for motion
- Damage to V1 - essentially blind
V3: form perception
V4: colour perception
V5: motion perception
Anterior Parietal Zone
-Somatosensory: processes somatic sensations & perceptions
Posterior Parietal Zone
-Integrate parietal and occipital functions to control movements (PE, PF, PG)